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Informatics

  • Project Period: 2013 to 2020

    MDSTARNet

    Abstract:

    CHEEC provided database support and applications development for the Muscular Dystrophy Surveillance Tracking and Research Network (MDSTARNet). The study is a multi-center multi-state research, tracking and surveillance effort that is identifying all people with childhood-onset Duchenne and Becker muscular dystrophies (DBMD). Collaborators are the Centers for Disease Control and Prevention (CDC), and researchers from Arizona, Colorado, Georgia, and New York. At the University of Iowa, the Iowa Registry for Congenital and Inherited Disorders is coordinating research efforts with assistance from the Iowa Department of Public Health.

    Go to the CDC website for further information: http://www.cdc.gov/

  • Project Period: 2012 to 2017

    Iowa Women's Health Study Drinking Water Exposures and Cancer Risk

    Collaborating Institution(s)
    National Cancer Institute
    Univ. of Minnesota School of Public Health
    CHEEC
    Abstract:

    This project involves analyzing drinking water contaminant data (nitrate, pesticides, disinfection byproducts) in Iowa municipal water supplies in communities where over 21,000 participants in the Iowa Women's Health Study resided during the 1960s through the 1980s. Drinking water exposure data is included with lifestyle, dietary and other data to evaluate risks for thyroid, bladder and ovarian cancer.

  • Project Period: 2010 to 2016

    Water Quality Data for Private Wells for the Agricultural Health Study Cohort

    Collaborating Institution(s)
    CHEEC
    State Hygienic Laboratory
    Abstract:

    This project will provide nitrate, pesticide and other water quality data for private wells and public water utilities across Iowa to use in modeling drinking water exposures for members of the Agricultural Health Study cohort.

  • Project Period: 2008 to 2016

    Exposure Assessment Method for Disinfection Byproducts in Drinking Water in the National Birth Defects Prevention Study

    Collaborating Institution(s)
    CHEEC
    NBDPS centers
    U.S. EPA
    University of North Carolina
    Abstract:

    The water exposure assessment subcommittee of the National Birth Defects Prevention Study (NBDPS) developed a detailed protocol and approach to assign disinfection byproducts (DBP) exposures in drinking water systems to residences in ten states. This project will enable the NBDPS, in conjunction with data on individual drinking water usage, to evaluate relationships between DBPs (trihalomethanes and haloacetic acids) in drinking water and select birth defects. The exposure assessment protocol includes linking the geocoded maternal address to the appropriate drinking water utility, obtaining all relevant DBP water quality data from that utility for that subject, and modeling water quality data to account for spatial and temporal variability. Centralized geocoding of the residences of NBDPS participant was conducted by ATSDR’s Geospatial Research, Analysis, and Services Program Office. CHEEC is linking geocoded residential addresses to water utilities, collecting DBP data for those utilities, and linking the DBP data to the residences where the mother resided 1 month prior to conception through the first trimester of pregnancy. The University of North Carolina, in cooperation with US EPA, is developing algorithms for models to account for spatial and temporal variability of DBPs.

  • Project Period: 2007 to 2008

    Comprehensive Assessment of Rural Health in Iowa: the Carroll County Well Water Study

    Collaborating Institution(s)
    Carroll County (IA) Environmental Health Department
    CHEEC
    Iowa Department of Public Health
    University Hygienic Laboratory
    Funding Agency
    Iowa Department of Public Health
    National Center for Environmental Health
    Abstract:

    Intensive private drinking water well sampling in Carroll County, Iowa, will be conducted in 2007 – 2008 as part of the Comprehensive Assessment of Rural Health in Iowa (CARHI) project. This sampling will be a cooperative effort with the ongoing Iowa Statewide Rural Well Water Survey Phase 2 (SWRL2), a three year project (2006-08) conducted by CHEEC in collaboration with the Iowa County Health Departments and County sanitarians, the Iowa Departments of Public Health and Natural Resources, and other agencies. The intensive sampling effort in Carroll County will include 50 wells for the entire suite of SWRL2 compounds (nutrients, bacteria, metals, pesticides and herbicide degradates). Research questions of interest for this set of wells include are there seasonal variation for certain analytes in a confined geographic area (county), and what are the risk factors related to well characteristics/proximate sources of contaminants for poor water quality? An additional 100 wells will sampled and analyzed for total coliform bacteria, E. coli, enterococci, somatic coliphage, and chloride, as part of a special microbial monitoring study conducted by the University Hygienic Laboratory. The research objectives of the microbial monitoring study are to determine the incidence of enterovirus in private drinking water wells, to determine the occurrence of traditional and non-traditional fecal indicators in groundwater (e.g. somatic coliphage, chloride, and enterococci), and to determine whether the source of fecal pollution is human (by utilizing a human specific molecular marker).

  • Project Period: 2007 to 2012

    Nitrates, Nitrites and Nitrosatable Drugs and the Risk for Selected Birth Defects

    Collaborating Institution(s)
    Texas A&M University
    University of Iowa (CHEEC, Iowa Registry for Congenital and Inherited Disorders)
    National Birth Defects Prevention Study Centers
    Funding Agency
    National Institute for Environmental Health Sciences
    Abstract:

    Congenital defects are the greatest contributor to infant mortality in the U.S., but the causes for the majority of these defects are either unknown or poorly understood. Amine- and amide-containing (nitrosatable) drugs and other compounds react with nitrite in the stomach to form N-nitroso compounds, which have been found to induce a variety of congenital malformations in animal studies. Previous epidemiologic studies have focused on the separate effects of nitrates, nitrites, and nitrosatable drugs on risk of congenital malformations without consideration of their interaction in the formation of N-nitroso compounds. This study is examining the separate and joint effects of prenatal exposures to nitrates, nitrites, and nitrosatable drugs on the risk for neural tube defects, limb malformations, oral clefts, and heart defects. Cases and controls were obtained from the National Birth Defects Prevention Study (NBDPS), a CDC-funded study that covers populations in 10 different states. Subjects' usual intake of dietary nitrates, nitrites, and nitrosamines was calculated from a food frequency survey. The subject survey will also have information on medications taken one month pre-conception and during the first trimester; these will be classified as to their likelihood of nitrosatability based on the literature and chemical structure. Addresses of Iowa and Texas participants are being linked to community water systems and water nitrate sampling results. The separate and joint effects of nitrosatable precursors on risk of selected malformations will be analyzed. The effects of vitamins C and E (inhibitors of nitrosation) on the relations between nitrate/nitrite intake and nitrosatable drugs and risk of congenital malformations will also be examined. Use of over-the-counter medications is fairly common during pregnancy; several over-the-counter preparations contain nitrosatable compounds as active ingredients. This study will help us understand whether pregnant women who take nitrosatable drugs and also consume greater amounts of nitrates and nitrites are at increased risk of having offspring with birth defects

  • Project Period: 2004 to 2007

    CARHI

    Collaborating Institution(s)
    UI Departments of Geography, Occupational and Environmental Health, and Family Medicine
    Funding Agency
    CDC
    Abstract:

    Research and database management on the Comprehensive Assessment of Rural Health in Iowa (CARHI) in collaboration with the UI Departments of Geography, Occupational and Environmental Health, and Family Medicine. Funding is provided by the CDC.

    Comprehensive Assessment of Rural Health in Iowa (CARHI)—NCEH is funding and providing technical oversight to a 2- to 3-year cooperative surveillance activity that is generating baseline health data for selected rural communities in Iowa. With input from a CARHI committee of stakeholders, the Iowa Department of Public Health (IDPH) is linking environmental and health data from a rural community to allow investigation of health effects possibly associated with the environment, such as effects associated with agricultural exposures. The CARHI committee is developing a tool and process for collecting data and a CARHI database. The committee also is recruiting communities and health care practitioners to participate in the CARHI project. Public health officials will use CARHI data to monitor communities’ health, identify existing or emerging health problems that warrant further investigation, enhance or guide environmental sampling, conduct comprehensive health studies, or target important public health programs such as smoking cessation and safe farming practices.

  • Project Period: 1993

    Mammography Surveillance Pilot Studies

    Abstract:

    CHEEC provided data support for the Mammography Surveillance Pilot Study conducted in Scott County, Iowa. The study evaluated the feasibility of performing population-based mammography surveillance by identifying and linking Scott County patients receiving screening and diagnostic mammograms with their breast tissue pathology reports and breast cancer experience. 1993 is the study year. Specific aims of the study are: (1) Assess use and effectiveness of breast cancer mammography in Scott County for 1993, (2) Determine the need for changes in the practice of screening and in the workup of women with positive screening tests, and (3) Evaluate the feasibility of performing studies of biologic characteristics of screen-detected breast cancers and non-screen detected breast cancers. The Mammography Surveillance Pilot Study is participating in a consortium of similar surveillance studies. The consortium is committed to sharing common protocol, study design, and research objectives as well as comparable data collection procedures.

  • Project Period: 1993 to 2003

    Residential Radon and Lung Cancer Case-Control Study

    Abstract:

    Radon

    Heartland Radon Research and Education Program (HRREP)

    The Iowa Radon Lung Cancer Study

    Phase I Completed

    a Field, R.W., aLynch, C.F., bSteck, D.J., aSmith, B.J., aBrus, C.P., cNeuberger, J.S.,
    aWoolson, R.F., aFisher, E.F., d Platz,C.E., d Robinson, R.A.

    aCollege of Public Health
    University of Iowa

    b Physics Department
    St. Johns University

    c Department of Preventive Medicine
    University of Kansas School of Medicine

    dCollege of Medicine
    University of Iowa

    The Iowa Radon Lung Cancer Study was a large-scale epidemiology study initiated in 1993 and funded by the National Institute of Environmental Health Sciences (NIEHS). The study assessed the risk posed by residential radon exposure. The 5-year study was performed in Iowa and the participants were women throughout Iowa who lived in their current home for at least 20 years. Over a thousand Iowa women took part in the study. Four hundred and thirteen of the participants were women who had developed lung cancer, the remaining 614 participants were controls who did not have lung cancer. The study was limited to women, because they historically tend to spend more time at home and they have less occupational exposure to other lung carcinogens.

    The epidemiologic study was performed in Iowa for several reasons. Iowa has the highest average radon concentrations in the United States. In addition, women in Iowa tend to move less than most other states, which makes calculation of their past radon exposure easier. Iowa was also selected because it has a quality National Cancer Institute SEER cancer registry, which helped us identify women who developed lung cancer. Close to 60% of the basement measurements for both cases (participants with lung cancer) and controls (participants without lung cancer) exceeded the EPA's action level. Twenty-eight percent of the living areas for the controls and 33% of the living areas for the cases exceeded the EPA's action level of 4 pCi/L.

    The study used the most advanced radon exposure measurement techniques ever performed in a residential radon study. Numerous yearlong radon measurements were made in each participant's home. Outdoor radon measurements were also performed in addition to estimates of work place exposure. All these measurements were linked to where the participants spent the proceeding 20 years in order to get a cumulative radon exposure.

    The major paper reporting the findings was published in volume 151 of the American Journal of Epidemiology (pages 1081-1101) in 2000. The American Journal of Epidemiology is the premier scientific journal devoted to the publication of empirical research findings and methodologic developments in the field of epidemiologic research. Findings of the study were released to the press on May 25, 2000.

    Risk estimates for the Iowa Radon Lung Cancer Study were adjusted for age, active smoking, and education. For all lung cancer subtypes, there was a positive categorical trend (p = 0.05). Analyses restricted to the live cases and controls noted both a strong categorical (p = 0.01) and continuous trend (p = 0.03). The Iowa Radon Lung Cancer Study's estimated excess odds at 11 WLM5-19 (roughly equivalent to a 15-year exposure at an average radon exposure of 4 pCi/L) averaged 0.50 for both all cases and the live case subset. For the all-case category, large cell carcinoma exhibited a statistically significant trend for both the continuous (p = 0.04) and categorical (p = 0.03) risk estimates. However, the differences in the linear excess odds between histologic types was not statistically significant (continuous p = 0.58, categorical p = 0.65). Overall, these results suggest that cumulative radon exposure is a significant risk factor for lung cancer in women.

    The Iowa Radon Lung Cancer Study had several strengths. First, independent pathologic review was performed for 96 percent of the cases. Second, the study was carried out in Iowa, which has the highest mean radon concentrations in the United States. Third, the high radon concentrations in conjunction with a strict quality assurance protocol contributed to accurate and precise radon measurements. Fourth, the IRLCS criteria requiring occupancy in the current home for at least the last 20 years eliminated the need to impute radon measurements from missing homes. Fifth, the linkage between radon measurements and retrospective participant mobility allowed for a refined exposure estimate. The IRLCS risk estimates are in general agreement with the National Research Council's predicted cancer risk associated with indoor radon exposure. Overall, the risk estimates obtained in this study suggest that cumulative radon exposure in the residential environment is significantly associated with lung cancer risk.

     

    THE IOWA and MISSOURI RESIDENTIAL RADON STUDIES

    Phase II – Currently Underway

    RW Field, Ph.D. a, DJ Steck, Ph.D. b, BJ Smith, Ph.D.a, CF Lynch, M.D. Ph.D.a,
    JH Lubin, Ph.D.c, MA Parkhurst, Ph.D.d, MCR Alavanja, Dr. PH c

    aCollege of Public Health
    University of Iowa

    bPhysics Department
    St. John's University

    c National Cancer Institute
    Rockville, MD

    d Pacific Northwest National Laboratory
    Richland, WA

    Purpose

    The specific aims of the 5-year Iowa and Missouri Residential Radon Studies (Phase-II), which initiated in 2000 are to: 1) further refine the estimated lung cancer risk posed by residential radon-222 (radon) decay product exposure using a novel glass-based retrospective radon decay product (progeny) reconstruction detector; 2) determine the shape (linear, quadratic, etc.) of the dose-response curve relating radon progeny exposure and lung cancer; 3) determine the lung cancer risk posed by radon progeny exposure for the various histologic types; and 4) examine the association between radon progeny and other lung cancer risk factors on the lung cancer incidence. The study, using state-of-the-art methods to measure retrospective radon progeny exposure, focuses on the association between residential radon progeny exposure and lung cancer.

    Glass surfaces exposed to radon gas over an extended period of time are convenient radon progeny reservoirs that allow retrospective estimates of radon exposure. The novel glass-based detectors measure 210Pb previously embedded in glass through residual nuclei recoil implantation following alpha decay. Glass provides a stable matrix for the 210Pb deposit. The 22-year half-life of 210Pbmeans that it takes decades before the activity achieves an equilibrium value and the activity persists for years after exposure. This predictable temporal behavior provides a long-lasting marker for past radon and radon progeny concentrations in a home. Therefore, one can measure glass items that have been carried from home to home over long periods of time to estimate past residential radon progeny exposure. Because the radon progeny deliver the actual radiation dose to the lung tissues, rather than the radon gas itself, better residential radon progeny dose estimates require the reconstruction of actual airborne radon progeny concentrations. Pooling of data between two large-scale epidemiologic studies from a similar geographic area that used the glass-based detectors in addition to the contemporary radon gas detectors increases the power of the overall analyses. We anticipate the research will significantly reduce radon (more precisely radon progeny) exposure misclassification, which will enhance our ability to address the Specific Aims above.

    Study Design

    The study design has three major components: 1) field calibration and laboratory validation of the retrospective radon detectors, 2) reanalysis of the risk estimates from the Iowa Radon Lung Cancer Study incorporating radon progeny exposure estimates obtained from retrospective radon detector (RRD) measurements, rather than radon gas measurements; 3) calculation of risk estimates from a pooled analyses of retrospective radon detectors exposure results for the previous National Institutes of Environmental Health Sciences (NIEHS) funded Iowa Radon Lung Cancer Study (IRLCS) and the National Cancer Institute (NCI) funded Missouri Radon Lung Cancer Study II (MRLCS-II).

    Selected Findings

    Findings from the Iowa and Missouri Residential Studies have been published in over 25 peer-reviewed scientific journals. A few examples of some of the major findings follow.

    Risk Estimates for Prolonged Residential Radon Exposure Risk estimates for the Iowa Radon Lung Cancer Study using estimates of retrospective gas exposure were adjusted for age, active smoking, and education. For all lung cancer subtypes, there was a positive categorical trend (p = 0.05). Analyses restricted to the live cases and controls noted both a strong categorical (p = 0.01) and continuous trend (p = 0.03). The Iowa Radon Lung Cancer Study's estimated excess odds at 11 WLM5-19 (roughly equivalent to a 15-year exposure at an average radon exposure of 4 pCi/L) averaged 0.50 for both all cases and the live case subset. Large cell carcinoma exhibited a statistically significant trend for both the continuous (p = 0.04) and categorical (p = 0.03) risk estimates, but the differences in the linear excess odds between histologic types was not statistically significant. These results suggest that cumulative radon exposure is a significant risk factor for lung cancer in women.

    Improved Residential Radon Study Methodology – The a priori defined IRLCS radon-exposure model produced higher odds ratios than those methodologies that did not link the subject's retrospective mobility with multiple, spatially diverse radon concentrations. In addition, the smallest measurement errors were noted for the IRLCS exposure model. Risk estimates based solely on basement radon measurements generally exhibited the lowest risk estimates and the greatest measurement error. The findings indicate that the power of an epidemiologic study to detect an excess risk from residential radon exposure is enhanced by linking spatially disparate radon concentrations with the subject's retrospective mobility and that previous epidemiologic investigations likely underestimated the risk posed by residential radon exposure.

    State of the Art Radon and Radon Progeny Dosimetry - Radon progeny, rather than radon, deliver dose to the lungs during decade’s long exposures. The study has made advances in estimating contemporary and past radon progeny dose using passive integrating alpha detectors. Contemporary airborne radon and progeny activities are reconstructed from direct radon and surface deposited progeny measurements. Track registration material, with selected energy removing filters, detects the individual alpha emitting isotopic concentrations. These concentrations are used in a fate and transport model to calculate the available airborne dose rate. Retrospective radon progeny concentrations can be reconstructed from glass-implanted 210Po activity and the relationship between airborne and deposited activities determined from contemporary activities. Using a regression analysis of the IRLCS retrospective detector data to identify the important environmental variables, new detector modules, as well as the old, have been calibrated in controlled exposures. Active airborne progeny detectors are being developed and calibrated to directly sample the important environmental conditions and activities in a select group of homes to improve and validate the dose estimates.

    Diet and Lung Cancer - When comparing the fifth (highest) to the first (lowest) quintile of consumption of total fat, saturated fat and cholesterol in the IRLCS, we obtained odds ratios of 2.0 (1.3-3.1), 3.0 (1.9-4.7), and 2.0 (1.3-3.0), respectively for lung cancer. However, when red meat was entered into the model along with total fat, saturated fat or cholesterol, the excess risk for the macronutrients disappeared while an odds ratio of 3.3 (1.7-7.6) was obtained for red meat. The odds ratios for red meat consumption were similar among adenocarcinoma cases, OR=3.0 (1.1-7.9) and non-adenocarcinoma cases, OR=3.2 (1.3-8.3) and among life-time nonsmokers and ex-smokers OR=2.8 (1.4-5.4), and current smokers, OR=4.9 (1.1-22.3). Yellow-green vegetables were protective with an odds ratio of 0.4 (0.2-0.7). We concluded that consumption of red meat was associated with an increased risk of lung cancer even after controlling for total fat, saturated fat, cholesterol, fruit, yellow-green vegetable consumption and smoking history, while yellow-green vegetables are associated with a decreased risk of lung cancer.

    Gene Environment Interactions – Recent work with collaborators at the NCI and City of Hope (Los Angeles) have explored gene-environment interactions between residential radon, environmental tobacco smoke (ETS), and the GSTM1 null genotype. The sample series included lung cancer cases pooled from three previously completed case-control studies. Recent results show a statistically significant 3-fold increase in the interaction OR for GSTM1 null cases compared with GSTM1 present cases. In addition, the ETS and GSTM1 interaction OR was significantly elevated over two-fold. This is the first study to provide evidence of a radon and GSTM1 interaction in risk of lung cancer and supports the hypothesis that radon and ETS may promote neoplasia by damaging genetic pathways that include GSTM1. These findings have just been submitted for publication.

    Future Plans

    Laboratory calibration of the retrospective radon progeny detector is nearing completion and field validation studies are planned for fall of 2004. As soon as this work is complete, we will perform a reanalysis of the IRLCS data using the glass-based retrospective radon progeny data. Next, we will pool the glass-based retrospective radon progeny data from both the IRLCS and MRLCS. The pooled data should allow more power to examine the lung cancer risk posed by residential radon decay product exposure and determine whether the risk varies by histologic type. We are also continuing our collaboration with European investigators pooling the findings from all the residential radon studies that have used standard radon gas measurements and plan an eventual pooling of residential radon studies that incorporated the use of the more advanced glass-based measurements. Further collaborations are also underway with researchers at NCI and City of Hope (Los Angeles) to explore additional studies examining gene-environment interactions and lung cancer. We have archived paraffin fixed tumor specimens from the Iowa Radon Lung Cancer Study and welcome the opportunity of additional collaborations using these materials. We are also interested in performing future studies in Iowa, with the cooperation of the NCI SEER Iowa Cancer Registry, examining the impact of environmental causes of lung cancer in relation to energy balance in never-smoking individuals.


    Selected Peer-Reviewed Scientific Publications from the Iowa Residential Radon Study and On-going NCI-Sponsored Iowa and Missouri Residential Radon Studies

    1. Field RW, Steck DJ, Lynch CF, Brus CP, Neuberger JS, Kross BC. Residential Radon-222 Exposure and Lung Cancer: Exposure Assessment Methodology. Journal of Exposure Analysis and Environmental Epidemiology 6(2):181-195, 1996.
    1. Field RW, Smith BJ, Brus CP, Lynch CF, Neuberger JS, Steck DJ. Retrospective Temporal and Spatial Mobility of Adult Iowa Women, Risk Analysis: An International Journal 18(5):575-584, 1998.
    1. Fisher EF, Field RW, Smith BJ, Lynch CF, Steck DJ, Neuberger JS. Spatial Variation of Residential Radon Concentrations: The Iowa Radon Lung Cancer Study, Health Physics 75(5):506-513, 1998.
    1. Field RW, Lynch CF, Steck DJ, Fisher EF. Dosimetry Quality Assurance: The Iowa Residential Radon Lung Cancer Study, Radiation Protection Dosimetry 78(4):295-303, 1998.
    1. Steck DJ, Field RW, and Lynch CF. Exposure to Atmospheric Radon (222Rn) in Central North America, Environmental Health Perspectives 107(2):123-127, 1999.
    1. Field RW, Lynch CF, Steck DJ, Smith BJ, Brus CP, Neuberger JS, Woolson RF, Fisher EF, Platz CE, Robinson RA. Iowa Radon Lung Cancer Study, Radiation Research 151:101-103, 1999.
    1. Field RW, Steck DJ, Smith BJ, Brus CP, Neuberger JS, Fisher EF, Platz CE, Robinson RA, Woolson RF, Lynch CF. Residential Radon Gas Exposure and Lung Cancer: The Iowa Radon Lung Cancer Study, American Journal of Epidemiology 151(11):1091-1102, 2000.
    1. Field RW, Steck DJ, Smith BJ, Brus CP, Neuberger JS, Fisher EF, Lynch CF. The Iowa Radon Lung Cancer Study Phase I: Residential Radon Gas Exposure and Lung Cancer, The Science of the Total Environment 272:367-72, 2001.
    1. Steck DJ, Field RW. The Use of Track Registration Detectors To Reconstruct Contemporary and Historical Airborne Radon (222Rn) and Radon Progeny Concentrations for a Radon-Lung Cancer Epidemiologic Study, Radiation Measurements 31(1-6):401-412, 1999.
    1. Field RW, Steck DJ, Parkhurst MA, Hahaffey JA, Alavanja MCR. Intercomparison of Retrospective Radon Progeny Measurement Devices, Environmental Health Perspectives 107:905-910, 1999.
    1. Alavanja MCR, Field RW, Sinha R, Brus CP, Shavers VL, Fisher EL, Curtain J, Lynch CF. Lung Cancer Risk and Red Meat Consumption Among Iowa Women, Lung Cancer 34 (1):37 - 46, 2001.
    1. Field RW, Smith BJ, Lynch CF, Steck DJ. Intercomparison of Radon Exposure Assessment Methods: Implications for Residential Radon Risk Assessment, Journal of Exposure Analysis and Environmental Epidemiology 12(3):197-203, 2002.
    1. Steck DJ, Alavanja MCR, Field RW, Parkhurst MA, Bates DJ, Mahaffey JA. 210Po Implanted in Glass Surfaces by Long Term Exposure to Indoor Radon, Health Physics 83(2):261-271, 2002.
    1. Krewski D, Lubin J, Zielinski J, Alavanja M, Catalan V, Field RW, Klotz J, Létourneau E, Lynch C, Lyon J, Sandler D, Schoenberg J, Steck D, Stolwijk J, Weinberg C, Wilcox H A. A Combined Analysis of North American Case control Studies of Residential Radon and Lung Cancer: An Update. Radiation Research 158(6):785-790, 2002.
    1. Field RW. (Invited paper): A Review of Residential Radon Case-Control Epidemiologic studies Performed in the United States, Reviews on Environmental Health 16 (3), 2001.
    1. Field RW, Smith BJ, Platz CE, Robinson RA, Brus CP, Lynch CF. Agreement Between SEER Reported Versus Independently Reviewed Lung Cancer Morphologies: A Quality Assurance Analysis, Journal of the National Cancer Institute 96(14):1105-7, 2004.
    1. Krewski D, Lubin J, Zielinski J, Alavanja M, Catalan V, Field RW, Klotz J, Létourneau E, Lynch C, Lyon J, Sandler D, Schoenberg J, Steck D, Stolwijk J, Weinberg C, Wilcox HA. North American Case-Control Studies of Residential Radon and Lung Cancer, Journal of Toxicology and Environmental Health, In Press.
    1. Krewski D, Lubin J, Zielinski JM, Alavanja M, Field RW, Letourneau EG, Sandler DP, Schoenberg JB, Weinberg C, Wilcox S, Catalan V. Risk of Lung Cancer in North America Associated with Residential Radon, Epidemiology, In Press.

      For additional information on these studies contact:

      R. William Field, M.S., Ph.D.
      The University of Iowa
      College of Public Health
      Department of Occupational
      and Environmental Health
      Department of Epidemiology
      104 IREH
      Iowa City, Iowa 52242
      Phone: 319-335-4413
      Fax: 319-335-4225
      Email: bill-field@uiowa.edu

       

      **********************************************

      GENERAL RADON INFORMATION

      • Information on radon testing and mitigation is available toll free from the National Safety Council at 1-800-SOS-RADON, or by visiting the EPA Web site.
      • Maps of indoor and outdoor radon concentrations in the upper Midwest can be found at the Minnesota Radon Project map web pages.

       

      • R.William Field's keynote address titled Current National and International Scientific Radon-Related Activities and Educational Initiatives given at the Fifteenth National Radon Meeting in 2005. Download the PowerPoint presentation.

        Notes: This will download the powerpoint presentation to your computer. You will need Microsoft powerpoint to open/see the presentation. If you are having trouble, sometimes it is best to select the option 'Save file' when prompted, open powerpoint, and then open the downloaded file (CRCPDweb.ppt). In our tests, both Firefox and MS Internet Explorer browsers running on a Windows XP machine and the latest version of Microsoft office had no problem downloading and viewing the file. The file size is 2.14 MB. The full file path is http://cheec.uiowa.edu/sites/cheec.uiowa.edu/files/CRCPDweb.ppt.

      • RADON: Top 10 Reasons for Action. The following is a powerpoint presentation created by Dr. Field that may serve as a template for radon outreach presentations. The presentation builds in part on previous slides presented by the U.S. EPA for outreach purposes. Please feel free to use for your outreach activities, but acknowledgement of source of materials would be appreciated. Some of the slides in the presentation contain speaking notes under the slides. Download the PowerPoint presentation.

        Notes: This will download the PowerPoint presentation to your computer. You will need Microsoft PowerPoint to open/see the presentation. If you are having trouble, sometimes it is best to select the option 'Save file' when prompted, open powerpoint, and then open the downloaded file (Webtop10.ppt). In our tests, both Firefox and MS Internet Explorer browsers running on a Windows XP machine and the latest version of Microsoft Office had no problem downloading and viewing the file. The file size is 2.78 MB. The full file path is http://cheec.uiowa.edu//sites/cheec.uiowa.edu/files/Webtop10.ppt.

      • Radon: What you can't see can hurt youAn article appearing in the fall 2005 edition of Spectator, a University of Iowa Publication. The link will download a PDF document.

       

      Acknowledgements: We thank the National Institutes of Health: National Cancer Institute and National Institute of Environmental Health Sciences , Center for Health Effects of Environmental Contamination at the University of Iowa, Iowa Cancer Registry, and the participants and their caring families that made these studies possible.

    1. Project Period: 1993 to 2015

      Agricultural Health Study

      Abstract:

      CHEEC Data Management Center staff provided full computer support including database design and administration, system services and applications programming for the Agricultural Health Study for the first 13 years to this study. This study is funded by National Cancer Institute (NCI), the Environmental Protection Agency (EPA) and the National Institute of Environmental Health Sciences (NIEHS)has enrolled more than 60,000 people in Iowa. The University of Iowa College of Public Health is the lead investigator in Iowa. This large cohort will be followed for many year obtain detailed information on agricultural exposures, diet, and other factors which may be related to the development of cancer and other diseases. Information gathered will provide data on agricultural practices that can be helpful to farmers nationwide. For more information on the Agricultural Health Study, visit http://www.aghealth.org.

    2. Project Period: 1986 to 1987

      One Time Testing of Iowa Regulated Drinking Water Supplies

      Abstract:

      In 1986 the Iowa General Assembly passed House File 2303. This legislation mandated that the Iowa Department of Natural Resources (IDNR) must develop and implement a one-time analytical testing of the finished water from Iowa's publicly and privately owned water systems for 35 pesticide compounds and 35 volatile organic contaminants (VOC). The University Hygienic Laboratory (UHL) provided all analytical services to this program which ran from November 1986 to November 1987.

      Eight hundred and fifty-six public water systems were tested. One hundred and twenty-five tested positive for one or more pesticides. Five hundred and fifty tested positive for one or more synthetic organic compounds. No measurable concentrations of pesticides or volatile organic chemicals were found in 279 systems. A few water systems had pesticides or volatile organic chemical levels that exceeded U.S. Environmental Protection Agency health advisories or maximum contaminant levels, but contaminant levels high enough to cause an acute health risk were not observed in this study.

      The pesticides most commonly found were atrazine, cyanazine (Bladex), alachlor (Lasso), metolachlor (Dual), and 2,4-D. The most frequently found volatile organic chemicals belong to a group called trihalomethanes (THMs). THMs are formed during disinfection when chlorine reacts with organic matter in the water. Para- and meta-xylene, measured as a single compound, was the second most abundant VOC observed.

      The following are the most significant findings of this one time testing:

      • Surface water systems have the greatest potential for pesticide contamination.
      • The shallower ground water sources have a greater potential for contamination by pesticides and VOCs.
      • A seasonal trend in pesticide occurrences in water sources was not observed, with the exception of 2,4-D found at low levels.
      • The frequency of appearance and concentration of trihalomethanes in ground water systems serving small municipalities was unexpected.

      For a copy of this report, contact the University Hygienic Laboratory at (319) 335-4500.

    3. Project Period: 1983 to 2000

      Naturally Occurring Ammonia in Drinking Water Wells

      Collaborating Institution(s)
      University of Iowa Hygienic Laboratory
      CHEEC
      Funding Agency
      Iowa Department of Natural Resources
      Abstract:

      The (UHL) and the University of Iowa Center for Health Effects of Environmental Contamination (CHEEC), in collaboration with the Iowa Department of Natural Resources (DNR) Drinking Water Section, used existing databases and special monitoring efforts to conduct a statewide assessment of ground water quality and its relationship to certain public health outcomes. The study looked at the occurrence of ammonia, nitrite, nitrate and nitrifying bacteria in selected public water supplies. The study also included the linkage of analytical data maintained by the UHL and CHEEC, IDNR and health outcome data maintained by the Iowa Registry for Congenital and Inherited Disorders and the State Health Registry of Iowa. The study examined exposure to certain water contaminants and the incidence of various health outcomes at the community level. The study goal was to provide the State of Iowa with an ecological assessment of the occurrence and concentration of ammonia, nitrite, and nitrate-nitrogen in community water supplies and the risk for adverse health outcomes including, low birthweight, certain birth defects and certain cancers. Results of the investigation showed that systems with elevated ammonia concentrations in their source water had elevated nitrite and nitrate concentrations in their distributions systems. The results also indicated that bacterial growth, even with chlorination, was sufficient to lead to the reduction of ammonia and thus contribute to nitrite and nitrate concentrations in the distribution system. No adverse health outcomes, associated with the contaminants of concern, were identified in the study because of an insufficient study population. The report made several recommendations related to monitoring for ammonia and nitrite, as well as control of scaling and biofilms in water supply distribution systems.

    Cooperative

    • Project Period: 2018 to 2019

      Northeast Iowa Well Water Study

      Collaborating Institution(s)
      Center for Health Effects of Environmental Contamination
      University of Iowa College of Public Health (Department of Epidemiology and Department of Occupational and Environmental Health),
      U.S. Geological Survey
      IIHR Hydroscience and Engineering
      Iowa Geological and Water Survey
      National Cancer Institute
      State Hygienic Laboratory at University of Iowa
      Center for Health Effects of Environmental Contamination
      National Institute for Occupational Safety and Health
      Funding Agency
      Center for Health Effects of Environmental Contamination
      U.S. Geological Survey
      National Cancer Institute
      Investigator(s):
      Darrin Thompson, University of Iowa College of Public Health/CHEEC
      Bill Field, Hans-Joachim Lehmler, Charles Lynch, University of Iowa College of Public Health
      Susie Dai, John Vargo, State Hygienic Laboratory
      David Cwiertny, College of Engineering/CHEEC
      Rena Jones, Mary Ward, John Hofmann, Laura Beane-Freeman, National Cancer Institute
      Dana Kolpin, Michelle Hladik, US Geological Survey
      Cynthia Hines, National Institute for Occupational Safety and Health
      Abstract:

      Neonicotinoids are a relatively new class of insecticide, but have quickly become the most widely used class of agricultural insecticides in the world. Historically, neonicotinoid insecticides have been viewed as ideal replacements for more toxic compounds, like organophosphates, due in part to their perceived limited potential to impact the environment and human health. The use of neonicotinoids has become particularly intense in Iowa and neighboring states as a corn and soybean seed treatment. Few studies have been conducted to characterize human exposure to neonicotinoids or the insecticides potential health risks.

      Based on the increased intensity and geographic use of the more commonly used neonicotinoid insecticides in the U.S., pesticide applicators in Iowa have high potential for exposure from using corn and soybean seeds coated with neonicotinoids (see example of imidacloprid use Figure 1). Although the Agricultural Health Study (AHS) has been collecting information on pesticide usage and estimating exposures since 1993, AHS-based studies assessing neonicotinoid exposure and potential adverse health outcomes have not been performed. In fact, there have been no analytic epidemiologic studies performed nationwide that have assessed neonicotinoid-related adverse health outcomes using individual level exposure data.

      The long-term goal of the proposed research is to assess the health risk posed by chronic exposure to neonicotinoid insecticides and their metabolites. In addition, the study will assess exposure risks of other environmental contaminants such as nitrate, arsenic, lead, broad spectrum pesticides and their degradates, perfluorinated alkylated substances, antibiotics and pharmaceuticals, and selected microbes.

    • Project Period: 2018

      Investigation of prenatal and postnatal exposures in the etiology of breast and thyroid cancers in young adult Iowa women

      Collaborating Institution(s)
      Iowa Registry for Congenital and Inherited Disorders
      Wake Forest School of Medicine, Breast Cancer Program
      Iowa SEER Cancer Registry
      University of Iowa, Center for Public Health Statistics
      University of Maryland College of Behavioral and Social Sciences, Center for Geospatial Information Science
      University of Iowa, Reproductive Molecular Epidemiology Research and Education Program
      Funding Agency
      Iowa Center for Birth Defects Research and Prevention
      Population Health Seed Funds
      Center for Health Effects of Environmental Contamination
      Investigator(s):
      Paul Romitti, Charles Lynch, Jacob Oleson, Kristin Conway, University of Iowa College of Public Health
      Alexandra Thomas, Wake Forest University School of Medicine.
      Kathleen Stewart, University of Maryland
      Abstract:

      Breast and thyroid cancers pose an increasing health threat to young adult women ages 20-39 years in the United States (U.S.). Analysis of cancer surveillance data for the years 1992-2011 from 13 U.S. Surveillance, Epidemiology, and End Results (SEER) Cancer Registries identified that the annual incidence of Stage I-III hormone receptor-positive breast cancer among women ages 20-29 years and 30-39 years in Iowa, ranked second and fourth, respectively among the 13 registries. A recent review of Iowa SEER Cancer Registry data identified that the incidence of thyroid cancer has increased markedly from 1974-1983 to 2004-2013 among Iowa women ages 25-39 years. Even with this changing epidemiology, risk factors that contribute to these premenopausal malignancies are not well studied. Moreover, factors examined for postmenopausal breast and thyroid cancers do not seem to explain their increased incidence among premenopausal women. Because premenopausal breast and thyroid cancers are often hormonally mediated, their onset may be influenced by exposure to endocrine disrupting chemicals (EDCs), and such exposure could begin prenatally. To date, investigation of prenatal exposures and premenopausal breast and thyroid cancers is limited, and investigation of both prenatal and postnatal exposures is largely unexplored. As such, we propose to take full advantage of the high-quality, population-based cancer surveillance data collected by the Iowa SEER Cancer Registry and the multi-decade repository of population-based birth and death data maintained by the Iowa Registry for Congenital and Inherited Disorders to examine prenatal and postnatal exposures in the etiology of breast and thyroid cancers among a cohort of young adult Iowa women. We hypothesize that breast cancer and thyroid cancer in young adult Iowa women have geospatial predilections, suggesting estrogenic environmental risks from birth to diagnosis. For breast cancer, we also hypothesize that differences in endogenous hormone exposure are positively associated with increased incidence and worse outcomes for young adult women with hormone receptor-positive than those with hormone receptor-negative disease. To test these hypotheses, we aim to: 1) link cancer surveillance data with birth and death data to establish and describe a cohort of young adult Iowa women with breast or thyroid cancer; 2) conduct individual-level geospatial surveillance for young adult Iowa women with breast or thyroid cancer; and 3) examine associations between selected environmental exposures at birth and at diagnosis and development of breast or thyroid cancer in young adult Iowa women. In conducting these aims, we will eschew more traditional study designs, and instead, implement a population-based, life course, household-level design. Our proposed design also will allow us to easily incorporate annual updates of cancer surveillance and birth and death data to monitor future patterns of cancer occurrence and emerging exposures in this cohort. Elucidating etiologies of breast and thyroid cancers in young adult women is critical due to the prevalence of these diseases, as well as the marked personal and societal impacts of cancer diagnosis at a young age. Our study can help provide insights into these etiologies, an important step to developing interventions to reduce the incidence of these malignancies in young adult women.

    • Project Period: 2017

      Iowa statewide small community drinking water survey of lead, copper and arsenic

      Collaborating Institution(s)
      Iowa Institute for Hydraulic Research-Hydroscience and Engineering
      Sustainable Water Development Graduate Program, UI Department of Civil and Environmental Engineering
      Investigator(s):
      Michelle Scherer, Drew Latta, David Cwiertny, UI Department of Civil and Environmental Engineering
      Susie Dai, State Hygienic Laboratory at the University of Iowa
      Abstract:

      This project will address the issue of lead, copper, and arsenic in small community drinking water systems. Lead, copper, and arsenic are regulated in drinking water under the Safe Drinking Water Act (SDWA) due to their toxicity to human health. Over the last five years, 41 water systems in Iowa have exceeded the action level for Pb in their drinking water and 22 have exceeded the maximum contaminant level (MCL) for arsenic (impacted population = 23,393). This project will be a collaboration of CHEEC, the State Hygienic Laboratory, and IIHR-Hydroscience & Engineering to collect, analyze and map available Pb, Cu and As data from small community drinking water systems in Iowa, as well as identify twenty small communities to survey and measure Pb, Cu, and As, water quality parameters, and treatment methods. The goal is to make Pb, Cu, and As data easily accessible to communities and to provide recommendations to communities on how to avoid future Pb, Cu, and As releases to their water.

      Project Results:

      Since the Flint, Michigan, water crisis, public attention to the health effects of lead (Pb) and copper (Cu) in drinking water has increased. Unlike large water systems, small and medium-sized water systems are not required to provide corrosion control treatment under the U.S. EPA's Lead and Copper Rule (LCR). About 93% of Iowa’s public water systems are either small or very small water systems. Corrosion control treatment is only required in these smaller systems if the action levels for Pb and Cu are exceeded. The lack of continuous corrosion control treatment endangers the public health of consumers in these communities. Several water quality parameters, such as high chloride levels, low pH levels, high nitrate in pipes, household piping materials, type of water source, and treatment methods, are suspected to contribute to elevated concentrations of Pb and Cu. To explore potential causes of elevated concentrations of Pb and Cu, we are analyzing available Pb and Cu data for small community water systems in Iowa. Our goal is to provide a publicly accessible database as well as evaluate potential causes of elevated concentrations of Pb and Cu in Iowa drinking water. We hope the analysis will help inform and educate communities on how to keep their drinking water safe.

      The researchers are currenlty implementing the EPA method for measuring Pb/Cu and have collected public data available on Pb/Cu in Iowa drinking water systems. A database on Pb/Cu levels has been developed and can generate maps of Pb/Cu (and arsenic) exceedances in the state of Iowa. During fall 2018, the researchers will be sampling water systems in selected 20 communities.

    • Project Period: 2016

      Naturally-occurring radioactivity in private drinking water in Iowa: Understanding the potential for increased cancer risks to Iowans

      Collaborating Institution(s)
      UI Department of Radiology, State Hygienic Laboratory at the University of Iowa
      Investigator(s):
      Michael Schultz, UI Department of Radiology
      Michael Wichman, Dustin May, State Hygienic Laboratory at the University of Iowa
      Abstract:

      Naturally-occurring radioactive material can be a substantial source of radiation exposure to the public, especially in ground-derived drinking water. Two radionuclides from the uranium decay series (lead-210; Pb-210 and polonium-210; Po-210) are of particular concern because their characteristic properties combine to present potential carcinogenic risks to human. These radionuclides are present in subsurface geological deposits where a great deal of drinking water in the state of Iowa is derived. While the potential carcinogenicities are known, concentrations of Pb-210 and Po-210 are not well characterized in Iowa aquifers. This study proposes to determine the concentrations of Pb-210 and Po-210 in 50 privately-owned wells across the state to develop an understanding of the potential contribution to increased lifetime cancer risk to Iowans.It is expected that success in these studies will result in a more detailed understanding of the biogeochemical relationship of increased levels of Po-210 and Pb-210 to other natural radionuclides found in Iowa's well water, and will provide preliminary data for understanding potential risk of natural radioactivity in Iowa's well water.

    • Project Period: 2016

      Effect of co-exposure to air pollution and house dust endotoxin on asthma and wheeze

      Investigator(s):
      Angelico Mendy, Peter Thorne, UI Department of Epidemiology
      Darryl Zeldin, Paivi Salo, NIEHS
      Richard Cohen, Jesse Wilkerson, Social and Scientific Systems, Inc.
      Charles Weir, HHS Office of Emergency Management
      Abstract:

      Air pollutants and house dust endotoxin are ubiquitous in our environment. Air pollutants exacerbate pre-existing asthma and evidence is mounting that it may cause the disease through oxidative stress and destruction of the airway mucosa. Endotoxin is also well known to cause bronchial asthma, although research suggests it might be protective against the atopic phenotype, especially with early-life exposure. Animal studies suggest that co-exposure to both air pollutants and endotoxin may have worse consequences on respiratory health than individual exposures. This study will investigate the effects of co-exposure to environmental pollutants on asthma and wheeze in humans in a representative U.S. sample. The research will lead to an increased understanding of environmental risk factors for asthma and wheeze to enhance prevention of these respiratory conditions.

      Project Results:

      Homes in rural states with farming activities such as Iowa tend to have higher concentrations of endotoxin than the homes located in non-rural states. This work contributed to the better understanding of the association of endotoxin with respiratory diseases as well as the factors that might influence this relationship.

      The study had three primary findings.

      1. House dust endotoxin and ambient air pollution are risk factors for asthma and animal studies suggest that they might have a synergistic effect on asthma
      2. In a large sample representative of the US population which included 6,488 participants, researchers examined the association of co-exposure to endotoxin and ambient air pollutants such as particulate matter - 2.5 um (PM2.5), nitrogen dioxide (NO2), and ozone (O3) with asthma outcomes
      3. Researchers found that co-exposure to elevated levels of house dust endotoxin and ambient PM2.5 was synergistically associated with emergency room visit for asthma in the past 12 months in all participants and while co-exposure to elevated concentrations of house dust endotoxin and ambient NO2 was associated with the outcome only in children.
      Publications:

      Mendy A, Salo PM, Cohn, RD, Wilkerson J, Zeldin DC, Thorne PS. House Dust Endotoxin Association with Chronic Bronchitis and Emphysema. Environmental Health Perspectives (Online), 2018;126(3).

      Mendy A, Wilkerson J, Salo PM, Cohn RD, Zeldin DC, Thorne PS. Exposure and Sensitization to Pets Modify Endotoxin Association with Asthma and Wheeze. The Journal of Allergy and Clinical Immunology: In Practice. 2018 Apr 21. Epub ahead of Print

      Mendy A, Wilkerson J, Salo PM, Cohn RD, Zeldin DC, Thorne PS. Endotoxin predictors and associated respiratory outcomes differ with climate regions in the US. Environment international. 2018;112:218-26.

    • Project Period: 2014

      Development of novel, composite nanomaterials for water filtration

      Collaborating Institution(s)
      Savannah River National Laboratory (SRNL) funds to support GRA
      EPA funds (via Cwiertny/Parkin Labs) for lab equipment and supplies
      Investigator(s):
      Sarah Larsen, UI Department of Chemistry
      David Cwiertny, Gene Parkin, UI Department of Civil and Environmental Engineering
      Abstract:

      Approximately 1/3 of the world’s population lacks access to safe drinking water. Human exposures to drinking water contaminants, such as arsenic, have been linked to cancer, neurological, cardiovascular and pulmonary health problems. In a recent survey of private wells in Iowa, 48% were found to contain arsenic and 8% were determined to have arsenic levels greater than the EPA’s drinking water standard of 10 ppb. It is critical, both globally and locally, to develop improved methods for removing groundwater contaminants. Investigators in this study will design, fabricate and evaluate mesoporous silica-coated electrospun iron oxide nanofibers for arsenic adsorption from water. The Larsen Lab is developing functionalized mesoporous silica materials for adsorption of radioactive contaminants; these materials are also promising for application as arsenic adsorbents. The Cwiertny/Parkin Lab is developing electrospun nanofibers for use as chemically active filtration materials. CHEEC funds will allow the two Labs to work collaboratively to develop and evaluate these novel composite adsorbents.

      Project Results:

      This work produced materials of benefit for point of use treatment systems.  Many Iowans are subject to drinking water contaminated by chromium and copper as a result of degradation in their water distribution system.  Because these pollutants are generated during distribution, the only option for removal of these metals is through treatment devices installed at the point of use. By harnessing nanomaterials, we've produced a platform technology ideally suited for point of use treatment as a result of its small footprint and high capacity for metal uptake. Accordingly, outcomes of this work may one day help to improve drinking water quality for Iowans and others impacted by distribution system derived metal contaminants.

      The key results of the study are as follows.

      1. This work produced novel composites of silica and iron oxides for removal of metal from drinking water supplies.
      2. Composite materials were effective for uptake of copper and chromium, providing uptake capacity that was greater than expected from the performance of individual silica and iron oxides.
      3. The composites were also more mechanically robust and thus hold practical advantages over more traditional sorbent materials.
      Publications:

      S. Egodawatte, K.E. Greenstein, I. Vance, E. Rivera, N.V. Myung, G.F. Parkin, D.M. Cwiertny, S.C. Larsen (2016). Electrospun Hematite Nanofiber/Mesoporous Silica Core/Shell Nanomaterials as an Efficient Adsorbent for Heavy Metals. RSC Advances, 6, 90516-90525.

    • Project Period: 2012

      Occurrence of viruses and unregulated contaminants in Iowa public water supply groundwater

      Collaborating Institution(s)
      Iowa Department of Natural Resources, U.S. Geological Survey
      UI Department of Geosciences, U.S. Department of Agriculture
      Investigator(s):
      Robert Libra, Iowa Geological and Water Survey
      Michael Wichman, State Hygienic Laboratory
      Abstract:

      Groundwater supplies drinking water to about 80% of Iowa’s population; most Iowans obtain water from public water supplies (PWS), which are required by EPA to monitor finished water for various chemical, physical, and biological contaminants; raw source water monitoring is infrequently required. EPA publishes a Drinking Water Contaminant Candidate List detailing contaminants that may require standards and monitoring in the future. A strategy to assess future drinking water regulatory needs, and to guide source water protection activities for both public and domestic wells is targeted sampling and analysis of raw PWS groundwater for currently unregulated contaminants with public health and environmental concerns. This project will sample 66 Iowa PWS wells with known construction and hydrogeologic vulnerability for a number of contaminants. Funding for this project comes from EPA and Iowa DNR Drinking Water and Source-Water Protection programs. CHEEC funds will be used for sampling and analysis of PWS wells for human enteric viruses. The upcoming federal Unregulated Contaminant Monitoring Rule will have an emphasis on groundwater contaminants; this project will complement the national plan and establish Iowa as a leader in monitoring groundwater quality for contaminants with public health implications.

      Project Results:

      The work directly measured the quality of public water supply groundwater used by Iowans. It provides a baseline of contaminant occurrence and concentrations, allowing for challenges to current supplies and treatment systems to be realized in a timely manner. It also raised awareness of these unregulated contaminants with state agencies and water supply operators.

      The study's key findings include:

      1. Pharmaceuticals commonly detected at trace levels.
      2. Human viruses present, and possibly more common during wetter periods?
      3. No obvious analytical indicators of virus occurrence.
      4.  Wastewater constituents, either pharmaceuticals and/or viruses, present almost 60% of raw public supplygroundwater.
      5. A long-standing Iowa Geological Survey groundwater vulnerability methodology works relatively well for these emerging contaminants. 
    • Project Period: 2012

      Evaluation of a web-based approach to data collection in molecular environmental epidemiological investigations of adverse pregnancy outcomes

      Collaborating Institution(s)
      Iowa Registry for Congenital and Inherited Disorders
      UI Reproductive Molecular Epidemiology Research and Education Program
      Investigator(s):
      Paul Romitti, Kristin Caspers, UI Dept. of Epidemiology
      Gabriele Ludewig, UI Dept. of Occupational and Environmental Health
      Michael Wichman, State Hygienic Laboratory
      Peter Weyer, CHEEC
      Abstract:

      Wireless telephone use, caller ID, and call blocking pose challenges to telephone-based data collection for epidemiological studies; smartphones, tablets, and increased access to the internet have removed both time and place demands of home-based communications. Telephone-based data collection in Iowa for the NBDPS has indicated a steady decline in participation rates. This case-control study will evaluate a web-based approach for molecular environmental epidemiological studies of adverse pregnancy outcomes. 240 infants with selected birth defects and 240 infants without defects will be selected and equally assigned to a web-based or a telephone-based group. They will be administered a questionnaire for maternal environmental exposures; mothers in the web-based group will electronically sign a consent form to use residual newborn bloodspots for biomonitoring; for the telephone-based group, the U.S. Postal Service will be used for hand-signed informed consents. Participation rates, sample representativeness, exposure reporting, and costs between the web-based and telephone-based groups will be compared. Investigators hypothesize that improved participation rates will be seen in the web-based group, which will permit increased generalization of study results and increased statistical power for studies.

    • Project Period: 2011

      Iowa Statewide Rural Well Water Survey Phase 2 (SWRL2)

      Collaborating Institution(s)
      Iowa Private Well Owners
      Iowa County Public/Environmental Health Departments
      University Hygienic Laboratory
      UI College of Public Health
      Iowa Department of Natural Resources
      Iowa Department of Public Health
      Iowa Department of Agriculture and Land Stewardship
      U.S. Geological Survey
      U.S. Centers for Disease Control and Prevention
      ISU Department of Geologic and Atmospheric Sciences
      UI Center for Health Effects of Environmental Contamination
      Abstract:

      The Iowa Statewide Rural Well Water Survey Phase 2 (SWRL2) was conducted from 2006-2008. It served as a follow-up study to the original SWRL (1988-1989).

      SWRL2 study objectives were to examine trends in water quality since 1988–89 and collect baseline data for emerging contaminants. 473 private rural drinking water wells were sampled in 89 Iowa counties. 116 of the wells were original SWRL study wells; the other wells were randomly selected from the Iowa Department of Natural Resources Private Well Tracking System.

       

      Map of all the well sampling sites in Iowa

         SWRL 2 well sampling sites

      Findings from all of the sampled wells  include:

      Bacteria: 43% had total coliform  bacteria, 19% had enterococci, 11% had  E. coli

      Nitrate: 49% had nitrate; 12% had ≥10  mg/L (parts per million) nitrate-N, EPA’s drinking water standard for public water supplies

      Arsenic: 48% had arsenic; 8% had arsenic ≥0.01 mg/L, EPA’s drinking water standard for public water supplies

      Pesticides (parent compounds): 8% had atrazine at very low concentrations; 2% had metolachlor; acetochlor, alachlor and trifluralin were detected in <1% of wells

      Herbicide degradates (breakdown products of the parent compound): 11% had desethyl-atrazine, 11% had acetochlor ESA (ethane sulfonic acid), 27% had alachlor ESA, 33% had metolachlor ESA, and 8% had metolachlor OXA (oxanilic acid) 

      Health Assessment: This study did not set out to assess health risks associated with consumption of well water in Iowa. While some analysis showed levels of certain contaminants exceeding maximum contamination levels (MCLs) for public drinking water supplies, water quality in private drinking water wells is not regulated. Study-wide, no parent herbicide concentration was found to exceed a public water MCL. Herbicide degradate values were generally found at very small levels -- the mean for all degradates was 0.7 parts per billion (ppb) or less, with maximum values at 7 ppb. There are no established MCL values for degradates which are generally believed to be less toxic than their parent compound.

      SWRL2 fact sheet and full report are available for download (PDF):

    • Project Period: 2011

      Influence of Redox Fluctuations on Arsenic Dynamics in Iowa Aquifer Materials

      Collaborating Institution(s)
      Cerro Gordo County (IA) Department of Public Health
      Investigator(s):
      Michelle Scherer, Gene Parkin, Douglas Schnoebelen, Department of Civil and Environmental Engineering, UI
      Peter Weyer, Center for Health Effects of Environmental Contamination, UI
      Abstract:

      Arsenic is an emerging water quality issue in Iowa’s groundwater. According to the Iowa Department of Natural Resources, there are 69 public water supplies that utilize groundwater with arsenic concentrations greater than the recommended limit and in as recent survey of 473 private wells in Iowa, 48% were found to contain arsenic. This study will help address the issue of arsenic in groundwater by conducting laboratory experiments to better understand the geochemical processes controlling the release of arsenic from soils to groundwater. This project will build on previous work that developed analytical methods for measuring arsenic and investigating the reduction of arsenic by common soil minerals. The objectives of this study are to 1) determine the extent of arsenic incorporation and release from iron minerals commonly found in Iowa aquifers, and 2) measure the release of iron and arsenic from Iowa aquifer materials where arsenic has been identified in the groundwater.

    • Project Period: 2005

      The Iowa Beach Study

      Investigator(s):
      Eric O'Brien, Janice Boekhoff: Iowa Department of Natural Resources
      Peter Weyer, David Riley: UI Center for Health Effects of Environmental Contamination
      Michael Wichman, Nancy Hall: University Hygienic Laboratory
      Gregory Gray, Troy McCarthy, R. William Field, Tara Smith: UI College of Public Health
      Abstract:

      A prospective pilot study of beach users from three Iowa beaches was conducted in June-August 2005 to determine the number of self-reported gastrointestinal (GI) illness symptoms and skin irritation/rash symptoms in swimmers and non-swimmers, and to correlate those numbers with bacterial levels in beach water. Aims of the study were to determine GI illness and skin irritation/rash symptom numbers at freshwater beaches with nonpoint pollution sources and to evaluate the effectiveness of indicator bacteria as predictors of risk under unique lake conditions found in Iowa. Study staff visited beaches on a daily basis over six weeks to distribute study flyers, recruit participants and take water samples. One-thousand and thirty-nine people were recruited for the study. Of that number, 261 people participated on-line in a web-based system to collect baseline information, and completed follow-up surveys over four weeks which included questions about water activities, time spent at the beach, occurrence of GI illness or skin irritation, etc. Composite water samples were collected daily and analyzed at the University Hygienic Laboratory for E.coli, enterococci, and total microcystin toxin. Spearman correlation coefficients were calculated to compare beach indicator variables to GI illness and skin irritation/rash symptoms. Reported GI illness and skin irritation/rash episodes were correlated with indicator variables at each beach. Multiple regression analyses ranked beach indicator variables, bacterial levels in the water, and various interactions as risk factors for GI illness and skin irritation/rash episodes. Statistically significant associations between bacteria levels and reported illness included enterococci level and diarrhea at Beach 1, enterococci level and skin irritation/rash symptoms at Beach 2, and microcystin toxin level (<1 μg/L) and skin irritation/rash at Beach 1. The results of this pilot study indicate that more research is needed to determine if these associations exist on a larger scale at other inland beaches and to further explore the positive correlation between low levels of microcystin toxin and skin irritation/rash.

      A poster titled Microcystin Toxin and Enterococci Indicator Levels Associated with Freshwater Recreational Waterborne Illness was presented at the 2007 American Society for Microbiology conference by Nancy Hall.

    • Project Period: 2004

      Fate of Endocrine Disruptors, Antibiotics and Pharmaceuticals in Wastewater Treatment Plants

      Collaborating Institution(s)
      Iowa Department of Natural Resources (IDNR)
      Investigator(s):
      Gene Parkin, Craig Just, Department of Civil and Environmental Engineering, The University of Iowa
      Abstract:

      Biosolids are generally defined as the end-product of production and treatment of sludges generated during wastewater treatment. Beneficial uses of biosolids (e.g., land application, landfill covers, etc.) are expected to increase in the coming years. Wastewaters from domestic and industrial sources are known to contain relatively low concentrations of endocrine disruptors, antibiotics and pharmaceuticals. Most of what is known about the fate of these compounds comes from measurements taken before and after treatment of the liquid component of the wastewater. Very little is known about the fate of these compounds during processing of the solids generated during wastewater treatment. Many of these compounds are likely to partition onto particulate matter due to their hydrophobic nature. Thus, it is important to understand the fate of these compounds during the production and use of biosolids. Aqueous samples collected at points throughout a wastewater treatment plant were processed and analyzed for acetaminophen, caffeine, cotinine, ibuprofen, 4-nonylphenol, sulfamethoxazole, triclosan, and trimethoprim. Most aqueous phase removal occurred during primary clarification and/or activated sludge treatment while little or no aqueous phase removal resulted from secondary clarification or chlorination/dechlorination. Sorption isotherms determined for each compound on biosolids from the plant indicated compound specific sorption behavior. Caffeine, cotinine and acetaminophen were significantly removed from the aqueous phase during activated sludge treatment. This implicates biotransformation as a primary removal process given the low sorption potential of these chemicals. Sulfamethoxazole and trimethoprim also have low sorption potential, but are more chemically stabile such that only a small quantity of each was removed during activated sludge treatment. Ibuprofen, 4-nonylphenol and triclosan were significantly removed from the aqueous phase during activated sludge treatment, likely as a result of sorption processes as evidenced by high log Kow values and high concentrations of triclosan and 4-nonylphenol in analyzed biosolids.

    • Project Period: 2003

      Urinary Pesticide Metabolite Levels and Reproductive Effects: A Prospective, Pilot Study of Partners of Pregnant Women in Iowa

      Collaborating Institution(s)
      Study for Future Families
      Investigator(s):
      Paul Romitti, Department of Epidemiology, The University of Iowa
      Amy Sparks, Department of Obstetrics/Gynecology and Urology, The University of Iowa
      Abstract:

      This study hypothesized that the variance in semen quality between geographic locations may be related to recent exposure to environmental toxins, particularly agricultural chemicals. Prospective, multi-center studies have demonstrated geographical variations in semen quality. A recent study of semen quality in four US cities found male partners of pregnant women a rural center (MO) to have significantly lower sperm counts and motility than men recruited from urban centers (NY, MN and CA). A small study of men from this population residing in MO demonstrated an association between semen quality and levels of urinary pesticide metabolites, while men in MN had few detectable levels. The study proposed to examine the relationship between semen quality and urinary pesticide metabolites in partners of pregnant women receiving obstetrical care at University of Iowa Hospitals and Clinics. 

    • Project Period: 2002

      Iowa Community Private Well Study

      Collaborating Institution(s)
      The University of Iowa Hygienic Laboratory
      the UI Center for Health Effects of Environmental Contamination (CHEEC)
      UI Environmental Health Sciences Research Center (EHSRC)
      the United States Geological Survey
      the Iowa Department of Natural Resources
      County Environmental Health Specialists
      Investigator(s):
      Peter Weyer, David Riley: University of Iowa (UI) Center for Health Effects of Environmental Contamination
      Jessica Ferrie, UI Dept. of Occupational and Environmental Health, UI College of Public Health
      Michael Wichman, Lorelei Kurimski, Terence Cain, UI Hygienic Laboratory
      David Osterberg: UI Environmental Health Sciences Research Center
      Brent Parker, Iowa Department of Natural Resources
      Douglas Schnoebelen: U.S. Geological Survey
      Abstract:

      Conducted from June 2002-January 2003, the study aimed to achieve a better understanding of private drinking water wells in incorporated Iowa towns not served by a public water supply system. Water samples were analyzed by the University of Iowa Hygienic Laboratory (duplicate samples analyzed at USGS laboratories) for common use pesticides, nitrogen compounds, inorganics, bacteria, and VOCs. The study design contained a random and focused component. * Random Study Methodology: Approximately 103 drinking water wells from towns that did not have a public water supply were selected. A weighted distribution of households from US Census data was employed to select wells (i.e.- towns with a higher number of households stood a greater chance of having a well selected). County environmental health specialists visited these towns, located randomly generated points on maps, and found the nearest building to draw a water sample. Fifty distinct towns had one or more wells sampled. * Focus Study Methodology: The focus study employed the use of existing databases of potential contamination sources to intensively sample 15 communities. Selection criteria for these towns considered: towns utilizing private septic systems, existence of underground storage tanks, location of agricultural grain and chemical storage dealerships, regional hydrogeology, active and closed landfills, feedlots, railroad systems, industries in violation of wastewater permit applications (including stormwater permits), nearby uncontrolled sites identified by the Iowa Department of Natural Resources (IDNR), and Resource Conservation and Recovery Act (RCRA)/Superfund sites. 

    • Project Period: 1999

      Antibiotics in Surface Water

      Collaborating Institution(s)
      United States Geological Survey
      Investigator(s):
      Peter Weyer, Center for Health Effects of Environmental Contamination, The University of Iowa
      Dana Kolpin, United States Geological Survey, Water Resource Division, Iowa District
      Abstract:

      In 1999, CHEEC and the Iowa District of the United States Geological Survey (USGS) joined in a collaboratively funded project investigating the presence of antibiotics/antimicrobials in Iowa surface waters. The study objectives are to provide baseline data for types of antimicrobial compounds present, concentrations, and geographical distribution. Thirty sites from across the state were selected representing a cross section of large and small watersheds and stream flows. Of secondary importance of this study was for laboratory methods development for detection of these compounds. Thirty-one sites from across the state were sampled, representing large and small stream flows. Streams were sampled once during the first peak runoff event following snow melt in April 1999. These 15 distinct antibiotics were sampled: carbadox, spectinomycin, sulfamethoxazol, erythromycin, sulfamethazine, trimethoprin, erythromycin - H2O, sulfachloropyrizadine, tylosin, ivermectin, sulfadimethoxine, virginiamycin, lincomycin, sulfamerazine, and tetracyclines (total). Analytical results show that 16 of the 31 stream samples had positive detections for antibiotics. Sulfamethazine was detected in 10 samples, tetracycline (total) in 6, and lincomycin in 1. One stream had two detections of a single compound. All of the concentrations were below .5 micrograms/L (parts per billion). The results of this work were first presented at a 1999 USGS meeting titled Effects of Animal Feeding Operations on Hydrologic Resources and the Environment. Proceedings are available at http://water.usgs.gov/owq/AFO/proceedings/afo/index.html.

      Findings from this initial reconnaissance laid the groundwork for the the Kolpin et al journal article in Environmental Science and Technology, titled Pharmaceuticals, Hormones, and Other Organic Wastewater Contaminants in U.S. Streams, 1999-2000: A National Reconnaissance; Environ. Sci. Technol., 36 (6), 1202 -1211, 2002

      For a more thorough discussion of emerging contamination of water sources, see the USGS Toxic Substances Hydrology Program.

    • Project Period: 1999

      Analysis of Environmental Exposures in Hoop Structures and Conventional Confinement Swine Barns

      Collaborating Institution(s)
      The Leopold Center for Sustainable Agriculture, Iowa State University
      The University of Iowa Office of Vice President for Research
      Investigator(s):
      Peter Thorne, Department of Environmental and Occupational Health, The University of Iowa
      Dwaine Bundy, Department of Agriculture and Biosystems Engineering, Iowa State University
      Abstract:

      A major health concern in swine farming is inhalation of toxicants, which may lead to significant morbidity among swine farmers. Exposures to hydrogen sulfide, ammonia, dust and endotoxin have been linked to a number of health problems in workers, including upper airway diseases, lower airway diseases and interstitial diseases. In addition, outdoor air quality in proximity to swine operations has become a major concern in recent years. Neighbor complaints have been increasing as swine units become larger and more densely located in the neighboring community. While health effects related to odors from livestock units are very difficult to determine, the public perception that odors contain toxic substances has resulted in reports of headaches, nausea and other health complaints in neighbors. In recent years, hoop structures have emerged as an alternative method of housing hogs, and appear to have environmental benefits (related to air and water quality) in comparison to conventional confinement facilities. The purposes of this study are to 1) quantify airborne contaminant concentrations and exposure duration in hoop barns and conventional confinement barns controlling for location, season, micrometeorological conditions, animal density and other factors, and 2) to compare the exposure of airborne contaminants around and downwind of hoop structures and conventional confinement structures. The study will be conducted utilizing a pork producing farm with 3-5 hoop barns and 3-5 confinement buildings on a nearby site. The 15-month project will be a joint effort of researchers from The University of Iowa and Iowa State University; field sampling will be coordinated between study staffs, and laboratory analyses will be conducted utilizing labs at both institutions (ISU Odor Laboratory, ISU Animal Science Department, UI Inhalation Toxicology Facility), which specialize in specific contaminant identification and quantification.
      CHEEC, the Leopold Center for Sustainable Agriculture, and the UI Office of the Vice President for Research conducted a study titled 'Analysis of Environmental Exposures in Hoop Structures and Conventional Confinement Swine Barns' . The study was an effort to quantify and describe airborne compounds present in both both types of swine production facilities and potential exposures to workers and area contaminations. Research was completed 2000.

    Seed

    • Project Period: 2018

      Harmful Algal Bloom Detection at Ultra-High Spatial and Temporal Resolution Using Small Unmanned Aircraft Systems

      Investigator(s):
      C. Markfort, Department of Civil and Environmental Engineering, The University of Iowa
      G. LeFevre, Department of Civil and Environmental Engineering, The University of Iowa
      M. Skopec, Iowa Lakeside Laboratory
      Abstract:

      Researcher teams at IIHR – Hydroscience & Engineering propose to develop new drone-based technology for water quality measurements, in collaboration with Iowa Lakeside Laboratory, to provide rapid and high-resolution detection of potentially harmful algal blooms (HABs) in Iowa lakes and reservoirs. We will develop a tool that combines remote sensing cameras and unmanned aircraft systems (UAS) to conduct on-demand and rapid sampling of water quality without the need for chemical water testing. This pilot study will utilize infrared and multispectral camera instruments mounted on a heavy payload octocopter UAS or drone, which was developed and operated by Markfort's Environmental Fluid Mechanics and Renewable Energy lab to characterize atmospheric boundary layer winds and terrestrial surface properties including vegetation, to detect HABs.

    • Project Period: 2018

      Engaging Iowa citizens to measure and understand lead in their drinking water

      Investigator(s):
      D. Latta, Department of Civil and Environmental Engineering, The University of Iowa
      M. Scherer, Department of Civil and Environmental Engineering, The University of Iowa
      K. Dalrymple, School of Journalism & Mass Communication, The University of Iowa
      Abstract:

      We propose to engage, encourage, and enable the public to participate in collecting and analyzing their own drinking water for lead (Pb). Lead is regulated in drinking water under the Safe Drinking Water Act (SDWA) due to its toxicity to human health. In Iowa, 41 water systems have exceeded the action level for Pb in their drinking water since 2012, impacting a population of 18,039 people in the last 5 years. We propose to work with community partners in Iowa to evaluate whether Pb test kits can be used by citizens to accurately detect and measure Pb in their drinking water. We also propose to survey Iowa citizens to evaluate their understanding of Pb in drinking water and attitudes towards drinking water quality. We will focus on gaining a better understanding of what Iowans know about their current drinking water quality as well as their perceptions of risks posed by Pb in their drinking water. Our work will address the growing need for an educated and engaged citizenry committed to the sustainable management of water resources. Our proposal here is part of our long-term vision to create a sustainable drinking water lead monitoring program in Iowa.

    • Project Period: 2018

      Rapid Characterization Approach of Harmful Algal Blooms (HABs) Cyanobacteria in Iowa Waters

      Investigator(s):
      S. Dai, M. Schuller, M. Yacopucci, W. Aldous, R. Jepson, N. Hall
      State Hygienic Laboratory at the University of Iowa
      Abstract:

      Harmful algal blooms (HABs) caused by cyanobacteria are a serious environmental problem in natural water. Exposure to cyanobacteria metabolites can lead to human poisoning and animal mortality. The proposed study will focus on investigating the major HAB species in Iowa by analyzing samples from the current State Beach Monitoring Program. Microcystin positive environmental samples will be used for isolate cultivation and strain library construction. A unique mass spectrometry platform, so called Matrix Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF-MS), will be used to develop a rapid strain identification assay. This integrated approach will help determine the major cyanobacteria species that lead to algal blooms in Iowa and establish a cyanobacteria library for rapid species identification. The constructed cyanobacterial library will be shared resources for the research community. Findings from this study will help facilitate environmental risk management and develop mitigation strategies to reduce human and animal health risk.

    • Project Period: 2018

      Quantifying viral and bacterial pathogens in Iowa’s karst landscape for a quantitative microbial risk assessment

      Investigator(s):
      E. Baack, Department of Biology, Luther College
      J. Enos-Berlage, Department of Biology, Luther College
      Abstract:

      Winneshiek County in NE Iowa experiences elevated rates of some waterborne diseases. The area’s karst geology, which provides rapid routes for surface contaminants to reach aquifers, springs, and streams, leads to exposure risks via well water consumption and contact with recreational surface waters, both of which are prevalent in the region. To address these risks, we will collect pathogen data needed for the exposure assessment step of a quantitative microbial risk assessment, as well as pathogen source information necessary for risk management. Samples will be collected from 20 wells during the spring and from 7 surface waters following summer rainfall events. Quantitative PCR will be used to establish the abundance of diverse water-borne pathogens. In addition, species-specific fecal markers will be quantified to establish sources.

    • Project Period: 2017 to 2018

      Fate of Neonicotinoid Insecticides in Water and Wastewater Treatment Systems

      Collaborating Institution(s)
      University of Iowa, Department of Civil and Environmental Engineering
      U.S. Geological Survey
      Investigator(s):
      David M. Cwiertny
      Gergory H. LeFevre
      Dana W. Kolpin
      Abstract:

      Neonicotinoids represent one of the most heavily used pesticide classes, particularly for corn and soy production. Despite their ubiquity in Midwestern water resources, little is known about their fate in the environment, particularly engineered treatment systems intended to mitigate risk their exposure. This work is motivated by our overriding hypothesis that chemical and biological processes used in conventional treatment alter the structure of neonicotinoids so as to remove their specificity to invertebrates, thereby exposing non-target organisms, including humans, to unanticipated risks arising from their bioactive transformation products in finished water and effluent. Our research plan integrates laboratory studies simulating conventional water and wastewater treatment processes with monitoring of neonicotinoid removal and transformation at the University of Iowa Water Treatment Plant. Outcomes will provide the first insights into best practices for neonicotinoid removal during treatment and better understanding of the risks associated with their formation of unintended transformation byproducts.

      Project Results:

      The research measured emerging contaminants in drinking water from non-point sources and determined their fate and transformation, as well as developed new innovative technologies, consistent with the 1987 Iowa Groundwater Protection Act. The study demonstrated, for the first time in the world, that specific emerging pesticides are present in drinking water, which presents a human health exposure route. This work to assess fate and transformation could potentially help to inform future toxicology studies.

      These discoveries will improve the informational available to every Iowan on the quality of their drinking water. Additionally, the technologies used in conventional and advanced water treatment systems will better enable municipalities and citizens to have the safest water possible. The CHEEC seed grant was further leveraged to obtain a highly competitive federal research grant, which will further illuminate research related to safe water. Researchers are currently working to develop new technologies for water quality sensing that could make detection safer, faster, and less expensive, and even create a new start-up venture. The research conducted in the CHEEC seed grant, which has been substantially leveraged with other resources, provides direct and tangible benefits to improve water quality and protect public health for the people in the state of Iowa. 

      Key findings of the project include:

      1. -Neonicotinoid insecticides, present in rivers used for drinking water sources, are present in finishing drinking water, which we discovered for the first time
      2. -Neonicotinoids are not removed using conventional coagulation-floculation drinking water treatment
      3. -More advanced treatment methods, such as granular activated carbon, were significantly more effective at removal
      4. -Drinking water disinfection processes (i.e., chlorination) can transform neonicotinoids present in drinking water
      5. Low level human exposure to neonicotinoids may occur via drinking water.

       

      Publications:

      Klarich, K. L., Pflug, N. C., DeWald, E. M., Hladik, M. L., Kolpin, D. W., Cwiertny, D. M., & LeFevre, G. H. (2017). Occurrence of neonicotinoid insecticides in finished drinking water and fate during drinking water treatment. Environmental Science & Technology Letters, 4(5), 168-173.

    • Project Period: 2017

      Endocrine disrupting compounds in water sources: Development of a functionalized silicon nanowire biosensor for detection and quantification in complex mixtures

      Investigator(s):
      F. Toor, Department of Electrical and Computer Engineering, The University of Iowa
      G. LeFevre, Department of Civil and Environmental Engineering, The University of Iowa
      Abstract:

      Endocrine disrupting compounds (EDCs) in water negatively impact aquatic organisms and expose human consumers. This project develop a novel silicon (Si) nanowire (NW) biosensor to detect EDCs, specifically estrogenic substances, in-situ for complex environmental mixtures. This biosensor will contain NWs functionalized with human estrogen receptors (ERs) that generate a change in recorded electrical signal when chemical compounds with estrogenic bioactivity bind to the ERs, such as natural (estrone, E1) or synthetic (ethinylestradiol, EE2) hormones. This project is an innovative advancement of a compact, low-cost and high sensitivity optoelectronic sensing technology that facilitates real-time detection of EDCs in complex, unknown mixtures present in the environment. Our biosensor will detect compounds that bind to receptors as organisms “see” EDCs rather than simply measuring chemical presence. Investigators propose two novel sensor designs and will test sensitivity and robustness against current technologies. This work will facilitate deeper understanding of detecting EDC water sources.

    • Project Period: 2017

      Predictive model of the fate and transport of antibiotic resistance genes in Iowa rivers

      Investigator(s):
      K. Ikuma, C Rehmann, Department of Civil, Construction and Environmental Engineering, Iowa State University
      Abstract:

      The aquatic environment can act as a reservoir for antibiotic resistance genes (ARGs) and therefore contribute to human health risk. Effluent discharges from wastewater treatment plants (WWTPs) provide a constant and significant point source of environmental ARGs even in agricultural areas like Iowa. As the first step towards accurate risk assessment of the environmental dissemination of antibiotic resistance, a predictive and quantitative model of ARG persistence in Iowa rivers will be constructed and evaluated. The tasks of the proposed work involve constructing and evaluating a model that accounts for physical, chemical, and biological mechanisms of fate and transport of ARGs. Modeling will start with mass balances applied to the water column, suspended particles, sediment bed, and biofilms. The model will be evaluated by comparing with measurements in controlled laboratory microcosms and field measurements in the Ames, IA WWTP and its receiving river.

      Project Results:

      This project involves constructing and testing a model to predict the fate and transport of antibiotic resistance genes (ARGs) in rivers. Rivers, streams, and lakes can act as a reservoir for ARGs and therefore contribute to human health risk. Two important sources of ARGs in the environment are effluent discharges from wastewater treatment plants and runoff from agricultural areas. As a step toward developing a more comprehensive approach, the model will start by focusing on the first of the two, and it will be evaluated with results from controlled laboratory experiments and field measurements in the South Skunk River near Ames. A reliable model will help in predicting the risk to human health posed by antibiotic resistance in Iowa and elsewhere.

      Important findings from this study included:

      1. Wastewater treatment plants contribute not just intracellular antibiotic resistance genes (iARGs) but also extracellular ARGs (eARGs).
      2. eARGs are an underestimated form of ARGs that can be transported through rivers and spread antibiotic resistance in environmental bacteria.
      3. A preliminary model of the fate and transport of ARGs in streams has been developed that incorporates both iARGs and eARGs.
    • Project Period: 2017

      Identification of antibiotic resistance and virulence genes in Legionella found in hospital water using next generation sequencing

      Investigator(s):
      W. Hottel, Department of Epidemiology, The University of Iowa
      N. Hall, V. Reeb, L Desjardin, State Hygienic Laboratory at The University of Iowa
      Abstract:

      Legionella bacteria, a cause of pneumonia, are ubiquitous in the freshwater environment and man-made water systems. The majority of human disease is caused by L. pneumophila serogroup 1, although other strains and Legionella species can cause disease. Legionella species have a relatively high genetic diversity and the mobile transfer of genetic material is a mechanism for environmental Legionella to acquire virulence and antibiotic resistance genes, potentially increasing their pathogenicity. SHL has an extensive Legionella isolate collection from Midwest hospital water supplies providing a unique opportunity to look for antibiotic susceptibility and virulence genes in these isolates by whole genome sequencing using Next Generation Sequencing. The presence of virulence and antibiotic resistance genetic markers in environmental Legionella isolates cultured from hospital water could provide important information on the potential risks resulting from infection with these bacteria and whether water control measures are indicated to prevent hospital-acquired Legionnaires’ disease.

      Project Results:

      Legionellosis caused by Legionella bacteria has been increasingly reported in the United States and is a serious public health threat. Legionella are ubiquitous in the freshwater environment and in man-made water systems (e.g. hot water heaters, cooling towers, hot tubs) where they can infect humans through aerosolization and cause disease. Since its addition to the Centers for Disease Control's (CDC) Waterborne Disease and Outbreak Surveillance System in 2001, Legionella bacteria have been the single most commonly reported pathogen identified in drinking water-associated outbreaks.

      The greatest proportion of illness is attributed to L. pneumophila serogroup 1. A better understanding of the presence of virulence and antibiotic resistance genetic markers in L. pneumophila serogroup 1, other Legionella species and L. pneumophila serogroups cultured from hospital water could provide important information on the potential risks resulting from exposure and infection with these bacteria. This information will add knowledge to help answer the controversial question if the presence of these non-pneumophila environmental isolates in hospital water supplies requires eradication.

      There were four key findings of the study.

      1. Whole genome sequencing (WGS) identified antibiotic resistance and virulence genes in Legionella pneumophila and Legionella anisa isolates.
      2. Only a subset (Sequence Type 1) of L. pneumophila isolates contained a resistance gene for a current antibiotic treatment (macrolides) for Legionnaires’ disease.
      3. All L. anisa isolates had a beta-lactamase associated gene, which was not found in any of the L. pneumophila isolates
      4. L. pneumophila isolates had significantly higher prevalence rates of virulence genes than L. anisa isolates as determined by WGS.
    • Project Period: 2017

      Prairie strips for retaining antimicrobial resistant organisms

      Investigator(s):
      A.C. Howe, M.L. Soupir, M. Helmers, Department of Agricultural and Biosystems Engineering, Iowa State University
      ; L.A. Schulte, Department of Natural Resource Ecology and Management, Iowa State University
      T. Moorman, National Laboratory for Agriculture and the Environment, USDA-ARS
      Abstract:

      Antimicrobial resistance is a serious threat to both animals and humans. The large number of farm animals receiving antibiotics and their close contact with soil and water resources pose a public threat to the increasing emergence of antimicrobial resistance and ineffective drug treatments. Consequently, methods to mitigate the transport and spread of antimicrobial resistance are critically needed. Prairie strips are a conservation practice that uses strategically placed native prairie plantings in crop fields and have been shown to reduce the movement of soil and water from the agricultural environment. The study hypothesis is that prairie strips can also mitigate the spread of antimicrobial resistance genes and bacteria to the environment. This project develops a pilot system to test the retention of manure-associated resistance genes and bacteria in installed prairie strips and evaluates its benefits for surrounding soils and   waters. 

      Project Results:

      Previous research has documented that prairie strips are effective at reducing the amount of sediment, phosphorus, and nitrogen leaving farm fields and moving to surface and ground water. This project extended the researchers' work to quantify whether prairie strips can also contain field-applied manure and related material, including antimicrobial resistant genes and organisms, within the agricultural environment and out of water.

    • Project Period: 2017

      Colorimetric sensing of environmental fluoride contaminants using chemically-reactive triamidoborane ligands

      Investigator(s):
      S. Daly, Department of Chemistry, The University of Iowa
      Abstract:

      Developing molecular sensors that can accurately detect elevated fluoride concentrations in groundwater is an important, but challenging goal. Fluorosis – a health condition that stems from chronic consumption of excess fluoride from mineral deposits and industrial pollution – results in severely debilitating bone deformations and other life-threatening ailments in many parts of the world. Optical sensors that change color in response to aqueous fluoride would offer an inexpensive method to detect high fluoride levels in drinking water, but there are two challenges that have yet to be fully addressed: (1) selectivity for fluoride over competing analytes, and (2) high binding affinity for fluoride in water. Previous research demonstrated that metal-bound triamidoborane ligands (TBDPhos) can selectively bind fluoride while bound to transition metals. Here we propose to chemically modify our colorless TBDPhos ligands to produce an optical change in response to fluoride binding so they can be used in fluoride sensing applications.

      Project Results:

      The research aimed to provide colorimetric sensors that rapidly and selectively detect environmental contaminants in groundwater in Iowa and beyond. Current research funded by CHEEC is focused on detecting excessive fluoride contamination in water stemming from industrial run-off and natural fluoride deposits because excessive fluoride intake can lead to severely debilitating bone deformations and other life-threatening ailments (i.e. fluorosis). While fluoride was the primary focus, it should be emphasized that this research laid the foundation for selectivity detecting other toxic contaminants such as cyanide.

      Primary findings made in support of this goal:

      1. Developed new fluorescent metal complexes that bind fluoride. The fluorescence of the metal complexes are quenched upon fluoride binding, yielding an optical response for potential sensing applications.
      2. Prepared new fluoride binding ligands that impart aqueous solubility to metal complexes so they can be used for aqueous detection.
      3. Researchers also gained a better understanding of the role of ligand protonation on fluoride binding, and have computed how ligand protonation and ligand variations affect the free energy of fluoride binding. 
      Publications:
    • Project Period: 2017

      Solid state NMR studies of the photodegradation of air pollutants on TiO2

      Investigator(s):
      SC Larsen, Department of Chemistry and Center for Global and Environmental Research, The University of Iowa
      Abstract:

      Photocatalysts, such as TiO2, can be used to degrade a wide range of organic contaminants found in polluted air. TiO2 photocatalysts are active at ambient temperatures and pressures in the presence of UV irradiation and oxygen and have been shown to oxidize toluene, trichloroethylene (TCE), methanol/ethanol and many other organic compounds. In this proposal, solid state MAS NMR (magic angle spinning nuclear magnetic resonance) techniques will be utilized to identify surface species formed during heterogeneous photocatalytic oxidation reactions on TiO2. These surface species may be reaction intermediates, surface poisons or partial oxidation products. Spectroscopic studies of TCE enhancement of toluene photooxidation will be conducted to determine the origin of the enhancement for deactivation. The proposed research will provide insight into the role of surface species in photocatalytic oxidation reactions on TiO2 that could lead to the development of improved photocatalysts.

    • Project Period: 2017

      Naturally-occurring radioactivity liberated by new natural gas mining technologies: A pilot study of the geochemical partitioning and potential for radionuclide migration and exposure to higher organisms and humans

      Investigator(s):
      M. Schultz, Departments of Radiology and Radiation Oncology, The University of Iowa
      T. Forbes, Department of Chemistry, The University of Iowa
      Abstract:

      New drilling and hydraulic-fracturing technologies have unlocked economically-lucrative reserves of natural gas and the practice is proliferating rapidly. However, solid and liquid waste from these activities are enriched in naturally-occurring radioactive materials (NORM). Further, sediments downstream from wastewater treatment facilities are enriched in NORM. Similarly, NORM levels in solid waste are too high for disposal in many municipal facilities and are often buried on homesites. This pilot study will collect and analyze surface water, sediments, and plants at a wastewater treatment site in West Virginia that accepts hydraulic-fracturing wastewater, and will also collect and determine the leachability of NORM from solid-waste.         

      Publications:

      Nelson AW, Eitrheim ES, Knight AW, May D, Mehrhoff MA, Shannon R, Litman R, Burnett WC, Forbes TZ, Schultz MK. Understanding the radioactive ingrowth and decay of naturally occurring radioactive materials in the Environment: An analysis of produced fluids from the Marcellus Shale. Environ health Perspec. 2015 123(7):689-696.

      Nelson AW, Johns AJ, Eitrheim ES, Knight AW, Basile M, Bettis EA, Schultz MK, Forbes TZ. Partitioning of naturally-occurring radionuclides (NORM) in MArcellus Shale produced fluids influenced by a chemical matrix. Environ Sci Processes Impacts 2016 18(4):456-463

    • Project Period: 2016

      Discovering links between environmental contaminant clusters and environmental, geographic and social drivers using network-based data processing

      Investigator(s):
      A. Sen Gupta, Department of Electrical and Computer Engineering, The University of Iowa
      Abstract:

      This seed project spans two interdisciplinary collaborations across the College of Engineering, and College of Public Health that harness the power of information science and signal processing towards better understanding of contaminant fingerprints in the environment. In particular, the PI will investigate data-driven associations linking contaminant clusters to environmental, geographic and social drivers. This project will develop a data-driven infrastructure towards robust interpretation of raw signal and processed field  data, along with prediction models for success of intervention methods. While the focus of the work is chemical contaminants, the methods here apply equally to biological contaminants, e.g. water-borne fecal pathogens in soil and water. 

    • Project Period: 2016

      Environmentally active surface films

      Investigator(s):
      S.K. Shaw, J.S. Grant, Department of Chemistry, The University of Iowa
      Abstract:

      This research will address an emerging avenue for pollutant fate and transport in the active surface film. Surface films are composed of organic (waxy) and inorganic (salty) species which combine in dynamic, heterogeneous matrixes on nearly all impervious surfaces. The films work as ‘environmental sponges’ by mediating fate and transport of volatile and semi-volatile organic pollutants (OP), ultimately affecting human and environmental health. Our goal is to assign culpability of surface films’ physical morphology (roughness) and chemical maturity (oxidation state) to their participation in OP absorption and release. We propose to develop and expose proxy films to metered doses of known environmental maturation agents (i.e. UV radiation and ozone) and quantify the films’ morphology and interaction with OP as a function of film maturity. We predict the films’ heterogeneous character and dynamic behavior will significantly impact OP adsorption (and absorption), and that this behavior will trend with film hydrophobicity.

      Project Results:

      Researchers conducted detailed studies of environmental films that form on solid surfaces both indoors and outdoors.  The films can act as a sponge for 'persistent organic pollutants', which are chemicals that harm humans and human environments.  By better understanding the chemistry of these films, what chemicals may be absorbed or released can be better predicted, and when (i.e. hot, windy days or during rain-storms).  This will support better air and water quality monitoring and predictions.

      The study had three primary findings.

      1. Environmental films exhibit a large degree of heterogeneity
      2. Chemical profile exhibits fatty acids, triglycerides, saccharides, paraffins, metals, and inorganics such as phosphate, nitrate, and sulfate
      3. Water sorption differs between sampling sites, suggesting differing chemical profile and film hygroscopicity
    • Project Period: 2016

      Fate of neonicotinoid insecticides in water and wastewater treatment systems

      Investigator(s):
      D.M. Cwiertny, G.H. LeFevre, Department of Civil and Environmental Engineering, The University of Iowa
      D.W. Kolpin, U.S. Geological Survey
      Abstract:

      Neonicotinoids represent one of the most heavily used pesticide classes, particularly for corn and soy production. Despite their ubiquity in Midwestern water resources, little is known about their fate in the environment, particularly engineered treatment systems intended to mitigate risks of their exposure. This work is motivated by an overriding hypothesis that chemical and biological processes used in conventional treatment alter the structure of neonicotinoids so as to remove their specificity to invertebrates, thereby exposing non-target organisms, including humans, to unanticipated risks arising from their bioactive transformation products in finished water and effluent. Theresearch plan integrates  laboratory studies  simulating conventional  water and wastewater treatment processes with monitoring of neonicotinoid removal and transformation at the University of Iowa Water Treatment Plant. Outcomes will provide the first insights into best practices for neonicotinoid removal during treatment and better understanding of the risks associated with their formation of unintended transformation byproducts.

      Publications:

      Klarich KL, Pflug NC, DeWald EM, Hladik ML, Kolpin DW, Cwiertny DM, LeFevre GH. Occurrence of neonicotinoid insecticides in finished drinking water and fate during drinking water treatment. Environ. Sci. Technol. Lett. 2017; DOI: 10.1021/acs.estlett.7b00081.

    • Project Period: 2016

      Exposure to environmental obesogen tributyltin during early pregnancy in association with maternal obesity and gestational weight gain

      Investigator(s):
      W. Bao, Department of Epidemiology, The University of Iowa
      H.J. Lehmler, Department of Occupational and Environmental Health, The University of Iowa
      D.A. Santillan, M.K. Santillan, Department of Obstetrics and Gynecology, The University of Iowa
      K. Wang, Department of Biostatistics, The University of Iowa
      Abstract:

      Emerging evidence from animal studies has established tributyltin (TBT) as a novel environmental obesogen in the development of obesity and impaired metabolic function. However, data on health effects of TBT exposure in humans are lacking, indicating a critical and urgent need to translate the findings from animal studies to humans. This project is innovative in being the first to investigate the associations of prenatal TBT exposure during early pregnancy with maternal obesity and gestational weight gain. The Investigators will measure TBT concentrations in maternal plasma samples collected from 100 pregnant women at the first prenatal visit (<10 weeks of gestation). These samples have been already collected and archived in the University of Iowa Maternal Fetal Tissue Bank, an ongoing prospective cohort study. Maternal anthropometric measures, along with demographic and clinical data, will be extracted from confidential electronic health records.

    • Project Period: 2015

      Metagenomic analysis and modeling of environmental resistance to agricultural antibiotics

      Investigator(s):
      M. Soupir, A. Howe, Department of Agricultural and Biosystems Engineering, Iowa State University
      Abstract:

      Increasing levels of antibiotic resistance in clinical settings has led many to believe that animal agriculture antibiotic use is contributing to the global resistance problem; however, that connection is unclear given the limited understanding of antibiotic resistant bacteria (ARB) and resistant genes (ARG) in the soil and water environment. Our previous work has documented differences in ARG concentrations in drainage when compared to measured concentrations of U.S. EPA recommended indicator bacteria. Here, we propose laboratory experiments in a controlled column environment, representative of an agroecosystem, to (1) identify the diversity and quantify the abundance of ARGs and their hosts in manure, soils with varying management histories, and simulated subsurface drainage; and (2) identify the diversity and quantify the abundance of mobile genetic elements and their linkages to ARGs. Results will provide valuable insight into i) the microbial community harboring ARGs and ii) horizontal gene transfer processes occurring in agricultural systems.

    • Project Period: 2015

      A low-cost aerosol sensing estimator for assessing aerosol exposure

      Investigator(s):
      Sousan, T. Peters, Department of Occupational and Environmental Health, The University of Iowa
      G. Thomas, Department of Mechanical and Industrial Engineering, The University of Iowa
      Abstract:

      The association of air pollution with adverse cardiopulmonary health outcomes may be underestimated because of misclassification errors introduced by uncertainty in the exposure assessment of aerosols. Until recently, the excessive cost of high-end aerosol measurement devices (>$10,000) has prevented the regular collection of aerosol data with high spatial and temporal resolution with exposure measurements often being limited to a single site to represent large populations. In some cases, new, low-cost (<$500) aerosol devices have been found to correlate favorably to high-cost devices. However, these low-cost devices suffer from some limitations, such as an inability to distinguish between fine and coarse particles. The proposed study aims to overcome these limitations by designing and evaluating a customized, aerosol sensor based on low-cost, high-resolution cameras. The low-cost sensor will enable routine aerosol assessment among the general population, providing estimates of aerosol concentrations resolved by size (fine and coarse aerosol) and time (<5 min logging).

      Publications:
    • Project Period: 2015

      Metabolomics characterization of early biomarkers of microcystin exposure in blood

      Investigator(s):
      W. Rumbeiha, P. Imerman, Department of Veternary Diagnostic and Production Animal Medicine, Iowa State University
      A. Perera, WM Keck Metabolomics Research Laboratory, Iowa State University
      Abstract:

      Fresh water cyanobacteria harmful algal blooms (HABs) are increasing in frequency and severity in the U.S. and globally. Blooms produce potent and lethal cyanotoxins which poison people and animals. This is a serious emerging “One Health” problem. Among the many cyanotoxins produced by HABs are hepatotoxic and carcinogenic microcystins. Currently, the state-of-the-art diagnostic approach for microcystin intoxications in people is measuring elevated blood serum liver enzymes as biomarkers of effect. Unfortunately, elevated liver enzymes are late biomarkers of microcystin effects. The objective of this study is to identify and characterize early biomarkers of microcystin exposure and effects in humans using the mouse model. These early biomarkers will be used for diagnosis in populations exposed to contaminated water in order to mount early intervention procedures to protect individual and public health.

    • Project Period: 2014

      Estimating prenatal exposure to lead in Iowa newborns

      Investigator(s):
      A. Saftlas, K. Ryckman, Department of Epidemiology, The University of Iowa
      Abstract:

      Lead is a highly potent human toxicant that readily crosses the placenta of the developing fetus and impairs the development and function of multiple organ systems. Developing effective methods for measuring prenatal lead exposure and identifying women at risk for high lead levels in pregnancy is an essential public health priority. This pilot project will: 1) estimate the correlation of lead concentrations measured from 50 paired newborn dried blood spot and fetal cord blood samples; and 2) identify geographical “hot spots” for prenatal lead exposure in Iowa based on a consecutive sample of 1,866 Iowa newborns with lead concentrations measured from newborn blood spot cards. These pilot data will be used to design a larger investigation with the objectives of establishing baseline levels of lead exposure in newborns and identifying high-risk subgroups for intervention.

      Publications:
    • Project Period: 2014

      Toxicity of organophosphate and carbamate pesticides for neuronal and non-neuronal cells

      Investigator(s):
      J. Doorn, Department of Pharmaceutical Sciences and Experimental Therapeutics, The University of Iowa
      Abstract:

      Organophosphate (OP) and carbamate pesticides are widely used in agriculture. Acute exposure to high doses may cause cholinergic toxicity; however, recent work demonstrates that exposure to low levels causes adverse effects in humans from neurological deficits to oxidative stress/reactive oxygen species (ROS). The mechanism for this “non-canonical” toxicity is unknown but concerning given the ubiquitous nature of OP and carbamates in the environment and significant human exposure. Such adverse consequences are likely due to effects of these pesticides on cell types found in the brain other than cholinergic neurons, such as other neurons or glial cells (non-neuronal). The goal of this project is to determine which neuron types (i.e., cholinergic, glutamatergic, dopaminergic) or non-neuronal cells (i.e., astrocyte) are most sensitive to OP and carbamate pesticides, yielding toxicity and/or oxidative stress/ROS. In addition, the investigator seeks to identify the insulting species of the OP agent, i.e., phosphorothioate or bioactive oxon metabolite.

    • Project Period: 2014

      Simple and fast detection of pathogens in recreational waters

      Investigator(s):
      R. Cademartiri, Department of Chemical & Biological Engineering, Iowa State University
      M. Soupir, Department of Agricultural & Biosystems Engineering, Iowa State University
      Abstract:

      Harmful microorganisms are the leading cause of water quality impairments in the United States, and are thought to be responsible for 900,000 illnesses and 900 deaths per year. Quick and accurate detection techniques are badly needed to better identify waters posing a risk to human health. The objective of this study is to generate preliminary data in three important areas for the development of a paper-based test for the detection of pathogens in recreational waters: 1) the stability of bacteriophages on paper, 2) the pre-concentration of bacteria in water samples, and 3) the development of a sensitive colorimetric assay for bacteria on paper. The development of a paper-based device for detection of water-borne pathogens will provide information on the presence of pathogens in recreational waters at low-cost in a short period of time and can be used by volunteer groups, beach managers, and other public health officials.

      Project Results:

      This project explored a novel method for quick detection of fecal indicator bacteria, E. coli, on paper without the use of incubation.  This technology would be useful for quick detection of indicators in water quality, to determine if waters are safe for recreation.  While successful, the researchers were not able to get the detection limit of the methods to the level necessary for compliance with water quality standards.  E. coli could be detected on paper, but at concentrations that exceeded Iowa water quality standards.

      Publications:

      Hice SA, Santoscoy MC, Soupir ML, Cademartiri R. Distinguishing between metabolically active and dormant bacteria on paper. Appl Microbiol Biotechnol. 2017. https://doi.org/10.1007/s00253-017-8604-y

    • Project Period: 2013

      Predicting the transport and fate of emerging contaminants using multi-tracer characterization of reactive pathways

      Investigator(s):
      A. Ward, Department of Geoscience, The University of Iowa
      D. Cwiertny, Department of Civil and Environmental Engineering, The University of Iowa
      D. Kolpin, U.S. Geological Survey
      Abstract:

      Contaminants of emerging concern (CECs, unregulated compounds including pharmaceuticals and personal care products) are ubiquitous in environmental and drinking waters, posing potential risks to human and ecosystem health. This proof-of-concept study will characterize the transport and fate of CECs in a stream reach using a suite of tracers with well-characterized, complementary reactivities. Specific research tasks include quantifying reaction pathways within the environmental system, laboratory experiments linking tracer and CEC reaction rates, and numerical modeling to predict transport and fate of CECs. The overall goal of this research is to quantify reaction pathways in the environment and successfully predict the transport and fate of CECs. A major outcome will be a mechanistic understanding of transport and fate processes that can be applied to any CEC in the system; this will enable prediction of the spatial extent and temporal persistence of CECs in streams.

      Project Results:

      The field work in this SEED grant was conducted at Fourmile Creek in Iowa.  Until recently, Fourmile Creek had been an effluent dominated stream, impacted by discharge from nearby wastewater treatment plants. As a result, persistent pharmaceuticals (i.e., those not removed by wastewater treatment) were present in the Creek. However, their analysis is complicated by their trace levels and need for specialized instrumentation and sampling protocols. This SEED grant provided a proof-of-concept demonstration of how an easy-to-analyze trace (i.e., a dye) could be used to assess the fate of these emerging pollutant classes. With further validation and testing, this tracer approach may make it easier to assess the environmental fate of emerging pollutant classes in Iowa waters, and thereby provide better assessment of the risks posed to ecosystem and human health by the persistence of bioactive micropollutants.

      There were four important findings.

      1. The work explored whether a single, reactive tracer could be used to predict the fate of emerging contaminants in surface waters.
      2. Laboratory studies linked the reactivity of emerging pollutants to that of the reactive tracer, which then allowed the fate of emerging pollutants in the field to be predicted from the fate of the easier to analyze tracer (a dye).
      3. Field testing yielded mixed results. In some, but not all, instances, the reactive tracer was useful in anticipating the fate of more trace, harder to analyze emerging pollutants (e.g., pharmaceuticals).
      4. More work is needed to further refine and validate the method.
      Publications:

      Ward AS, Cwiertny DM, Kolodziej EP, Brehm CC. Coupled reversion and stream-hyporheic exchange processes increase environmental persistence of trenbolone metabolites. Nature Communications. 2015; 6.doi:10.1038/ncomms8067.

    • Project Period: 2013

      Effects of PCBs on adipocytes and the development of metabolic syndrome

      Investigator(s):
      A.J. Klingelhutz, Department of Microbiology, The University of Iowa
      Abstract:

      Recent epidemiological studies indicate that exposure to polychlorinated biphenyls (PCBs) is associated with an increased risk of metabolic syndrome, a group of disorders that includes obesity, glucose intolerance, high cholesterol, and hypertension. Metabolic syndrome increases the risk of developing type 2 diabetes. PCBs accumulate in adipocytes, which are known to play a key role in the genesis of metabolic syndrome. Recently generated extended lifespan human pre-adipocytes will provide a unique opportunity to assess the short and long term effects of PCBs on adipocyte biology. These cells will be used to test the hypothesis that exposure of adipocytes to PCBs causes long-term effects on gene expression to alter adipocyte differentiation and function. This study will lead to further understanding of how PCBs cause metabolic syndrome, may provide useful biomarkers for assessment of disease risk, and could point to new targets for therapy.

      Project Results:

      PCBs are contaminants of water, air, and food. The researchers' findings may be important for determining how PCB exposure leads to human disease. Further, the model systems developed can aid in evaluation of how other environmental contaminants may affect obesity and the development of diabetes.

      The study had four key findings.

      1. PCB126 inhibits the proper development of preadipocytes to adipocytes
      2. PCB126 acts through the aryl hydrocarbon receptor (AhR) in preadipocytes
      3. Activation of AhR in preadipocytes causes a proinflammatory response that inhibits proper adipogenesis
      4. Disruption of adipogenesis by PCB126 may be involved in the development of metabolic syndrome
      Publications:
    • Project Period: 2013

      Enhanced CNS exposure to glyphosate following inhalation resulting from olfactory uptake

      Investigator(s):
      M. Donovan, Department of Pharmaceutical Sciences and Experimental Therapeutics, The University of Iowa
      H. Lehmler, P. O’Shaughnessy, Department of Occupational and Environmental Health, The University of Iowa
      Abstract:

      While glyphosate, the ingredient present in the widely used RoundUp® family of herbicides, has an excellent safety profile following topical and oral exposure, it presents a potential CNS exposure risk if it is able to access the olfactory transfer pathways within the nasal mucosa. These pathways afford the opportunity for molecules to access the brain without needing to cross the blood-brain barrier. This pilot study will evaluate whether glyphosate and several commercial glyphosate herbicide formulations are able to permeate through the olfactory mucosa into the olfactory bulb and nearby brain regions following direct nasal instillation and aerosol exposure. Preliminary results will provide initial quantitative evidence regarding the risk of CNS glyphosate exposure following nasal inhalation and will support further investigations to evaluate the exposure risk along with identifying methods to limit inhalation exposure to herbicide applicators or those in close proximity to spraying operations.     

      Publications:

      Xu J, Li G, Wang Z, Si L, He S, Cai J, Huang J, Donovan MD. The role of L-type amino acid transporters in the uptake of glyphosate across mammalian epithelial tissues. Chemosphere 2016 145:487-494

    • Project Period: 2013

      Point-of-use electrocatalytic filters for reduction of persistent contaminants from drinking water

      Investigator(s):
      D. Cwiertny, D. Shuai, R. Valentine, Department of Civil and Environmental Engineering, The University of Iowa
      Abstract:

      Although regulated by the USEPA for the risk they pose to human health, nitrate and disinfection byproducts are pervasive contaminants often encountered in drinking water. Traditional approaches have proven inadequate for their removal; this project will develop a promising, point-of-use (POU) electrocatalytic filtration unit targeting these pollutants. With the potential for high pollutant removal efficiency and self-cleaning ability, this research will demonstrate the feasibility and sustainability of this technology. Specific tasks include synthesis and characterization of nanofiber supported metal catalysts exhibiting systematically varied physicochemical properties, assessing electrocatalytic filter performance when exposed to various water chemistries, and a preliminary environmental impact assessment addressing the cost and sustainability of this innovative technology. This work represents the first step in the development of a low-cost, POU water treatment device with the potential to lower health risks associated with drinking water sources compromised by persistent pollutant classes.

      Project Results:

      Drinking water supplies in Iowa are often contaminated with pollutants like nitrate and disinfection byproducts that adversely impact human health. Nitrate is a common problem in both public water systems and private drinking water wells, while disinfection byproducts are generated during water treatment with free chlorine and can also be produced during distribution via residual disinfectants. In both cases, an effective approach for limiting exposure to these pollutants is through treatment at the point of use (e.g., the tap).  Here, we've produced nanotechnology enabled treatment devices that may one day help to limit the exposure of Iowans to these common contaminants in their drinking water supplies.  Ongoing work is further refining this technology to improve performance and treatment efficiency.

      There were three key results of this study.

      1. Developed novel catalytic materials for point of use water treatment.
      2. Used a process known as electrospinning to fabricate nanofibers decorated with noble metals used as hydrogenation catalysts. These materials, when treated with hydrogen gas, were able to reduce common drinking water pollutants including nitrate and disinfection byproducts.
      3. Follow-up work, since funded by NSF, is using this platform to produce innovative, electroactive materials for treatment of nitrate in waste brines from ion exchange systems. The researchers have also received NSF funding to fabricate novel piezoelectric materials, which transform mechanical energy (e.g., vibrations) into electrons that can be used for reduction reactions. When these piezoelectric materials are coupled with the noble metal catalysts, the researchers are able to produce a more sustainable approach for point of use water treatment.
    • Project Period: 2012

      An investigation of carbon nanotube exposure assessment methods

      Investigator(s):
      P. O’Shaughnessy, R. Altmaier, A. Horne, Department of Occupation and Environmental Health, University of Iowa
      Abstract:

      Carbon nanotubes (CNTs) are engineered nanoparticles (<100 nm) that have been shown to cause adverse pulmonary outcomes in test animals. As such, the National Institute for Occupational Safety and Health (NIOSH) is considering a recommended exposure level (REL) for CNTs of 7 µg/m3, which is the limit of quantification (LOQ) of a method used to measure elemental carbon (EC) in diesel particles. Such a limit presents either an under- or over-exposure scenario with no information to determine actual conditions when below the LOQ. This pilot project will seek to establish a relationship between CNT particle count concentrations given known size distributions and EC mass concentrations to guide the interpretation of environments that may become contaminated with CNTs below the LOQ. A secondary objective will be to compare EC concentrations measured using the NIOSH method with those obtained from a hand-held device suitable for personal exposure assessments.

      Project Results:

      Many workplaces in Iowa produce indoor air hazards that may be harmful to workers. This study addresses those that produce carbon-containing particles in general, such as diesel exhaust, and those that produce engineered carbon nanotubes in particular.

      The study compared several methods for detecting airborne concentrations of carbon nanotubes (CNTs). The motivation for this work is related to recent recommendation by the U.S. National Institute for Occupational Safety and Health (NIOSH) to utilize their Method 5040 to detect carbon nanotube aerosol concentrations in workplaces. A novel device was developed to deposit a desired mass of CNTs on a filter for analysis by Method 5040. We determined that Method 5040 has a limit of detection that is not low enough to consistently measure concentrations below the recommended exposure level of 1 microgram per cubic meter established by NIOSH.

    • Project Period: 2012

      Functionalized magnetic mesoporous silica for adsorption of arsenic from water

      Investigator(s):
      S. Larsen, Department of Chemistry, University of Iowa
      Abstract:

      Access to safe drinking water is a global health issue. Human exposure to drinking water contaminants, such as arsenic, has been linked to cancer, neurological, cardiovascular and pulmonary health problems. The arsenic levels in 8% of private wells in Iowa were determined to be greater than the EPA’s drinking water standards of 10 ppb (0.01 mg/L).  Therefore, it is critical, both globally and locally, to develop improved methods for removing and analyzing arsenic in water. Mesoporous silica has well-defined pores of 1.5-10 nm and very high surface areas. Mesoporous silica can be readily modified through surface functionalization. In this study, functionalized mesoporous silica will be tailored to optimize arsenic adsorption. Specifically, mesoporous silica will be functionalized with thiol and/or amine functional groups which are expected to selectively adsorb As(III) or As(V) species, respectively. Magnetic iron oxide nanoparticles will be incorporated into the mesoporous silica to facilitate magnetic recovery from solution.  

      Publications:

      Lehman SE, Larsen SC.  Zeolite and mesoporous silica nanomaterials: Greener syntheses, environmental applications and biological toxicity. Environ Sci: Nano; 2014, 1, 200-213.

    • Project Period: 2012

      Sequence analysis of transferable genes encoding bacterial attachment and multi-drug resistance

      Investigator(s):
      L. Jarboe, Department of Chemical and Biological Engineering, Iowa State University (ISU)
      M. Soupir, Department of Agricultural and Biosystems Engineering, ISU
      L. Nolan, Department of Veterinary Microbiology and Preventive Medicine, ISU
      Abstract:

      The attachment of agricultural Escherichia coli isolates to environmental particles is significantly associated with multi-drug resistance. This association motivates our hypothesis that the genes responsible for bacterial attachment are encoded on a mobile genetic element that also encodes resistance and virulence. These mobile genetic elements are a group of transferable genes that can pass from one bacterium to another; plasmids are the most common form. Here, gene transfer confers not only resistance but possibly virulence. Thus, these genes are a possible environmental contaminant that could threaten human health. In this pilot-scale work we will first confirm that the genes encoding resistance and attachment can be co-transferred between bacteria. This would validate these genes as environmental contaminants. We will then sequence any plasmids transferred between bacteria during the transference of resistance and attachment. This would identify any virulence-associated genes, providing information about the threat that these plasmids present to human health.

    • Project Period: 2011

      Establishing a Methodology for the Detection of Silica Particles in Lung Cancer Tissue Using Computer-Controlled Scanning Electron Microscopy

      Investigator(s):
      K. Coleman, R.W. Field, Department of Occupational and Environmental Health, University of Iowa
      Abstract:

      Crystalline silica has long been recognized as an occupational hazard of the dusty trades with exposures resulting in silicosis. As recently as 1997, IARC categorized the respirable portion of crystalline silica as a Grade 1 human carcinogen indicating that silica may be implicated in the development of lung cancer. Evidence in the literature indicates that silica may be not only an occupational hazard, but an environmental hazard as well, with patients with no known exposure showing measurable quantities of silica within cancerous tissue samples. The primary goal of this study is to establish a methodology using Computer-Controlled Scanning Electron Microscopy to examine silica content in lung cancer tissue. Demonstrating that silica is not evenly distributed within the tissue will establish the need to use automated full scanning techniques, such as CCSEM, to guarantee that the analysis is not subject to random sampling error or researcher error, which may be rendering the traditional random sampling of zones for analysis under-representative of silica concentration in the tissue.

    • Project Period: 2011

      Enantiospecific Disposition of Chlordane in a Mouse Model Lacking NADPH-Dependent Cytochrome 450 Reductase

      Investigator(s):
      E.D. Oldham, I. Kania-Korwel, H.J. Lehmler, Department of Occupational and Environmental Health, University of Iowa
      Abstract:

      The  pesticide  chlordane  is  a  mixture  of  structurally  related,  highly chlorinated hydrocarbons and is a persistent environmental contaminant linked to a range of adverse health effects in animals. Most of the isomers are chiral, and may be metabolized in an enantiospecific manner. This type of metabolism has been shown for other chiral pollutants. We hypothesize that chiral chlordane isomers are metabolized enantioselectively by cytochrome P450 enzymes. To test this hypothesis we will take advantage of  a knockout mouse model lacking the  NADPH-dependent cytochrome P450 reductase, a critical enzyme in the catalytic cycle of P450 oxidation, and measure levels and enantiomeric fractions of chlordane and its metabolites in tissue from wild- type and knockout mice. This research will provide key mechanistic information about enantiospecific metabolism of chlordane, and can be extended to other pesticides commonly found in Iowa.

      Publications:

      Kania-Korwel I, Lehmler HJ. Chlordane and heptachlor are metabolized enantioselectively by rat liver microsomes. Environ Sci Technol 2013; 47:8913-8922.

      Wu X, Barnhart C, Lein PJ Lehmler HJ. Hepatic metabolism affects the atropselective disposition of 2,2',3,3',6,6'-hexachlorobiphenyl (PCB 136) in mice. Environ Sci Technol 2015; 49:616-625.

    • Project Period: 2011

      Using Human Enteric Viruses to Track Groundwater Contaminants to a Municipal Drinking Water Supply in an Alluvial Aquifer

      Investigator(s):
      W. Simpkins, Department of Geological and Atmospheric Sciences, Iowa State University
      Abstract:

      Alluvial aquifers are the most productive and widely used groundwater source for drinking water in Iowa. They are also the most vulnerable to contamination due to their shallow water table, hydraulic interchange with streams, and the potential for flooding. The Ames aquifer in Ames, Iowa is such an aquifer that is potentially vulnerable to contamination. The hypothesis that human enteric viruses enter the Ames aquifer from the South Skunk River and are transported to the municipal well field that supplies the Ames drinking water will be tested by analyzing river water and groundwater in piezometers and wells for viruses and stable isotopes along a groundwater flow path. The results will provide unique information about the extent and temporal variability of human enteric viruses in drinking water and demonstrate an innovative method (i.e., presence of viruses) to assess Groundwater under the Direct Influence of Surface Water (GWUDISW) in alluvial aquifers.

    • Project Period: 2011

      Pesticide Exposure and Risk of Endometriosis

      Investigator(s):
      E. Smith, L. Rubenstein, Department of Epidemiology
      B. Stegmann, Department of Obstetrics and Gynecology
      L. Fuortes, Department of Occupational and Environmental Health, The University of Iowa
      D. Sandler, J. Hoppin, National Institute of Environmental Health Sciences
      Abstract:

      Endometriosis is a chronic disease affecting ~15% of US reproductive-aged women, and is a significant cause of infertility. One suggested risk factor is exposure to organochlorines (OC). Diagnosed cases of endometriosis have been detected with longer exposure or higher serum concentrations than controls for OCs (PCDD, PCDF, and PCB/dioxin); however, study results have been inconsistent due partly to small numbers of cases/controls and limited exposure history. Analyses using the Agricultural Health Study will provide a significantly larger sample size for a case-control study and detailed measures of pesticide and environmental exposure to common agricultural pesticides and to these OCs. Study results will be used as pilot data for an National Institute of Child Health & Human Development (NICHD) proposal of clinic-based case-control study. In 2010, an NICHD Fertility Preservation Research Program, sought grants to characterize occupational and environmental exposures that may be associated with risks of infertility. This exposure and infertility issue continues to be of interest to NICHD. 

    • Project Period: 2010

      Siloxanes in Chicago Air

      Investigator(s):
      K. Hornbuckle, Department of Civil and Environmental Engineering, The University of Iowa
      C. Stanier, Department of Chemical and Biochemical Engineering, The University of Iowa
      Abstract:

      Siloxanes are organo-silicon compounds found in many industrial and consumer products like cosmetics, deodorants, and water repellants. More than one million tons of individual siloxanes, including those targeted in this proposal, are produced or imported in the US each year. As a result of their widespread use, they are found in wastewater and solid waste. They make their way into the environment through volatilization, wastewater discharge, and emission of landfill gases. This one-year pilot project focuses on the development of analytical methods for three cyclic siloxane compounds in air samples: octamethylcyclotetrasiloxane (D4); decamethylcyclopentasiloxane (D5); and dodecamethylcyclohexasiloxane (D6). The results will be used to develop a full-scale proposal for research on the emissions and transport of airborne siloxanes in Chicago and the surrounding Great Lakes.

      Publications:

      Yucuis RA, Stanier CO, Hornbuckle KC; Cyclic Siloxanes in Air, Including Identification of High Levels in Chicago and Distinct Diurnal Variation. Chemosphere 2013; pii S0045-6535 (13) 00359-7.

      Bzdek BR, Horan AJ, Pennington MR, Janechek NJ, Baek J, Stanier CO, Johnston MV. Silicon is a Frequent Component of Atmospheric Nanoparticles. Environ Sci Technol 2014; 48(19):11137-11145.

    • Project Period: 2010

      Analysis of the non-target growth effects of metolachlor on human HepG2 cells

      Investigator(s):
      K. Dhanwada, Department of Biology, University of Northern Iowa
      Abstract:

      This pilot project will analyze the growth inhibiting effects of the herbicide metolachlor on non-target, human HepG2 cells. Metolachlor, a very commonly used herbicide in the United States, especially in the Midwest corn-belt, functions by inhibiting chlorophyll and protein synthesis in target plants. Herbicide exposure has led to detrimental effects in several organisms, notably affecting their growth and behavior, however, its mechanism of action in non-target organisms is not yet clear. The EPA does not currently have specific regulations for maximal limits allowed in drinking water. Growth studies from our lab demonstrate that increasing metolachlor concentrations and increasing time of exposure results in decreased growth of liver cells. The objective of this study is to elucidate a mechanism for decreased HepG2 cell growth after metolachlor exposure. Analyses will include assessing toxicity effects leading to necrosis, effects of apoptosis induction and alterations in cell cycle progression

      Publications:

      Hartnett S, Musah S, Dhanwada KR; Cellular Effects of Metolachlor Exposure on Human Liver (HepG2) Cells. Chemosphere 2013; 90:1258-1266

    • Project Period: 2010

      Toxic Effects of Photolytic Transformation of Polybrominated Diphenyl Ethers (PBDEs) and Their Hydroxylated Compounds (OH-PBDEs)

      Investigator(s):
      Y. Suh and G. Ludewig, Department of Occupational and Environmental Health, University of Iowa
      Abstract:

      The flame retardants polybrominated diphenyl ethers (PBDEs) and their hydroxylated compounds (OH-PBDEs) are ubiquitously found in the environment. Human exposure to PBDEs occurs primarily via contaminated house dust. PBDEs are photolytically, chemically or metabolically transformed to more bioavailable and toxic products such as OH-PBDEs. OH-PBDEs may be converted to polybrominated dibenzo-p-dioxins (PBDDs) by solar or artificial UV light. We hypothesize that light irradiation of PBDEs and OH-PBDEs generates cytotoxic, genotoxic and cancer-initiating reactive products and that co-exposure to TiO2-nanomaterials enhances this reaction. To study this hypothesis we propose to 1) measure cytotoxicity, oxidative stress, genotoxicity, and cytochrome P450 (CYP) enzyme induction (as an indicator of the production of AhR agonist formation) in human HaCaT keratinocytes after exposure to irradiatiated OH-PBDEs, 2) determine the toxic effects of irradiation-products of PBDEs + nano-sized titanium dioxide (TiO2) or PBDEs alone and 3) investigate physico-chemical changes of OH-PBDEs and PBDEs + the toxicological impacts of PBDEs and OHPBDEs.

      Publications:

      Suh YW, et al. UVA/B-Induced Formation of Free Radicals from Decabromodiphenyl ether. Environ Sci Technol. 2009; 43(7):2581-2588.

    • Project Period: 2010

      Iron-induced Alveolar Epithelial Cell death Via Increase Ferritin Expression and p53 Activation

      Investigator(s):
      A. Comellas, Department of Internal Medicine, University of Iowa
      V. Grassian, Departments of Chemistry and Chemical and Biochemical Engineering, University of Iowa
      Abstract:

      A large amount of epidemiological and experimental studies indicate that particulate matter (PM), including, ultrafine particles, have close association with many respiratory and cardiovascular diseases. PM is a complex mixture of organic and inorganic airborne substance, generally composed of a core of ash or carbon, which is coated with organic molecules and transition metals of a broad size range. Between all the transition metals in PM composition, iron is almost always the most abundant in urban and rural areas. As a transition metal, iron is capable of generating reactive oxygen species (ROS) and contributing to oxidative stress, especially in the alveolar epithelium. Oxidative damage and cell death in the alveolar epithelium are the principal mechanisms attributed to PM and asbestos-induced lung injury. We hypothesize that iron content increases the expression of ferritin in alveolar epithelial cells (AEC), which in turn activates p53- dependent cell death pathway.

      Publications:

      Borcherding JA, Chen H, Caraballo JC, Baltrusaitis J, Pezzulo AA, Zabner J, Grassian VH, Comellas AP; Coal Fly Ash Impairs Airway Antimicrobial Peptides and Increases Bacterial Growth. PLOS ONE 2013; 8(2):es57673

    • Project Period: 2009

      Predicting Indoor and Outdoor Air Quality by Indirect Methods

      Investigator(s):
      N. Kumar, Department of Geography, University of Iowa
      Abstract:

      This research aims to develop indirect measures of indoor and outdoor air pollution, which can be used for computing personal exposure by linking an individual’s time-activity diary with the indirect estimates of indoor and outdoor air pollutions. Building on current research, satellite remote sensing will be used to estimate ambient air pollution at a household location. Imputing indoor air pollution, however, can be challenging. In this research indirect measures of indoor air quality will be identified by evaluating the indoor air pollution with reference to household characteristics, such cooking and heating fuel, flooring type, number of occupants, exchange of air between indoor and outdoor environments and ambient air pollution at the household location. The study will sample indoor and outdoor air quality, measured by fine and coarse particles (PM2.5, PM10, PM10-2.5), in 33 households in and around Iowa City during the fall 2008 and spring 2009. An incremental optimal sampling design will be adopted to draw the sample of households, which will capture more than 95% of the total variability in ambient air pollution. Particulates of different sizes will be monitored for a week in and outside of each household, and a brief questionnaire will be administered to collect the data on household characteristics. The analyses of these data using standard statistical methods will allow us to determine indirect measures of indoor air pollution.

    • Project Period: 2009

      Effects of Environmentally Induced Oxidative Stress on Regulator of G Protein Signaling (RGS) Proteins

      Investigator(s):
      D. Roman, Division of Medicinal & Natural Products Chemistry, University of Iowa
      Abstract:

      Environmental toxins, such as the herbicide paraquat, can cause damage to cells by inducing oxidative stress. 4-hydroxynonenal (4HNE) is the major lipid peroxidation product of oxidative stress and is highly reactive toward protein cysteine residues. RGS4 is a member of the Regulator of G protein signaling (RGS) protein family, and contains a cysteine residue (Cys148) that is sensitive to covalent modification, which irreversibly inhibits its function. RGS proteins are signaling checkpoints downstream of G protein coupled receptor (GPCR) activation and are critical for regulating the magnitude and duration of GPCR-mediated cell signaling events. We hypothesize that this sensitive site on RGS4 (Cys148) is modified during oxidative stress by 4HNE, thus inhibiting RGS4 function. As alterations in GPCR signaling and RGS protein function are evident in neurodegenerative diseases such as Parkinson’s, this proposal seeks to define the role of oxidative stress and 4HNE in RGS4 inhibition and subsequent cellular signaling dysfunction.

    • Project Period: 2009

      Monitoring Contaminant Impact on Biofilm Adaptation with Raman Spectroscopy

      Investigator(s):
      T. Peeples and J. Jessop, Department of Chemical & Biochemical Engineering, University of Iowa
      Abstract:

      The integration of biofilm flow devices with Raman scattering for bioanalysis and separation is a promising avenue to provide further information regarding complex mixtures of microbes and their adaptive mechanisms that facilitate contaminant biodegradation. To address the acquisition and induction of biotransformation activity, the first hypothesis is that Raman scattering can be used to identify and quantify members of biofilm communities. The second hypothesis is that biofilm formation leads to enhanced levels of atrazine degradation. The formation of biofilm can be evaluated using fluorescence and Raman techniques. Raman scattering can be used to evaluate the persistence of the model contaminant atrazine and metabolites in the flow systems. We expect to advance our mechanistic knowledge of induction in atrazine-mineralizing bacteria adapting to atrazine as a growth substrate. This project is therefore significant because improved bioremediation technologies will lead to reduced environmental contamination and reduce the associated risk to human health.

      Publications:

      Henry VA, Jessop JL, Peeples TL. Differentiating Pseudomonas sp. strain ADP cells in suspensions and biofilms using Ramen spectroscopy and scanning electron microscopy. Anal Bioanal Chem. 2017; 409:1441-1449.

    • Project Period: 2009

      Effect of In Utero Exposure to PCB 136 (2,2',3,3',6,6'- Hexachlorobiphenyl) Enantiomers on Neurodevelopmental Outcomes in Adult Offspring

      Investigator(s):
      I. Kania-Korwel, and HJ Lehmler, Department of Occupational and Environmental Health, University of Iowa
      Abstract:

      Polychlorinated biphenyls (PCBs) are a group of industrial chemicals that persist in the environment and cause adverse neurodevelopmental effects (such as altered brain ryanodine binding) in laboratory animals and in humans. Several neurotoxic PCB congeners, such as PCB 136, are chiral and, as we have shown recently, sensitize ryanodine receptors in an enantiospecific manner in vitro. We hypothesize that exposure to PCB 136 during gestation and lactation causes long-term neurodevelopmental effects in an enantiomer specific manner, with (-)-PCB 136 being more potent and efficacious than (+)-PCB 136. This hypothesis will be tested by investigating enantiomer specific differences (1) in the profile of PCB 136 and its metabolites and (2) brain ryanodine binding in mice exposed during gestation and lactation to (+)- and (-)-PCB 136.

      Publications:

      Kania-Korwel I, El-Komy MHME, Veng-Pedersen P, Lehmler HJ. Clearance of polychlorinated biphenyl atropisomers is enantioselective in female C57Bl/6 mice. Environ Sci Technol. 2010; 44:2828-2835.

      Kania-Korwel I, Duffel MW, Lehmler HJ. Gas chromatographic analysis with chiral cyclodextrin phases reveals the enantioselective formation of hydroxylated polychlorinated biphenyls by rat liver microsomes. Environ Sci Technol. 2011 45:9590-9596.

      Kania-Korwel I, Barnhart CD, Stamou M, Truong KM, El-Komy MHME, Lein PJ, Veng-Pedersen P, Lehmler HJ. 2,2',3,5',6-pentachlorobiphenyl (PCB95) and its hydroxylated metabolites are enantiomerically enriched in female mice. Environ Sci Technol. 2012; 46:11393-11401.

      Kania-Korwel I, Lehmler HJ. Assigning atropisomer elution orders using atropisomerically enriched polychlorinated biphenyl fractions generated by microsomal metabolism. J Chromat A. 2012;1278:133-144.

      Kania-Korwel I, Barnhart CD, Lein PJ, Lehmler HJ. Effect of pregnancy on the disposition of 2,2',3,5',6-pentachlorobiphenyl (PCB 95) atropisomers and their hydroxylated metabolites in female mice. Chem Res Toxicol. 2015; 28:1774-1783.

    • Project Period: 2009

      Effect of Nanoparticle Physicochemical Properties on Lung Surfactant Function

      Investigator(s):
      J. Fiegel, Division of Pharmaceutics and Department of Chemical and Biochemical Engineering, University of Iowa
      Abstract:

      The lung fluid interface plays an important role in stabilizing the lung during physiological processes such as breathing. Inhaled nanomaterials deposited on the lung fluid surfaces can adversely affect the stability and function of the fluid. However, biophysical and biochemical changes to this interface due to the deposition of nanoparticles with varying physicochemical properties have not been systematically studied. This project aims to elucidate the mechanisms by which nanoparticles alter the function of complex lung fluid interfaces through simultaneous surface rheological and tensiometric studies and fluorescence microscopy. We ultimately aim to develop new paradigms to predict loss of surfactant function based on nanoparticle physicochemical properties (size, surface area, surface charge, relative hydrophobicity and composition).

      Publications:

      Farnoud AM, Fiege J. Interaction of dipalmitoyl phosphatidylcholine monolayers with a particle-laden subphase. J Phys Chem B. 2013; 117:12124-12134

      Farnoud AM, Fiege J. Low concentrations of negatively charged sub-micron particles alter the microstructure of DPPC at the air-water interface; Colloids and Surfaces A: Physicochemical and Engineering Aspects. 415 (2102) 320-327

    • Project Period: 2008

      A Molecular Microbiological Search for Active Biphenyl Dioxygenases in Polychlorinated Biphenyl-contaminated Sediments

      Investigator(s):
      T. Mattes and K. Hornbuckle Department of Civil and Environmental Engineering, University of Iowa
      Abstract:

      Polychlorinated biphenyls (PCBs) are toxic, carcinogenic, and bioaccumulative compounds that are often found in lake and river soils and sediments. PCBs in soils and sediments represent a human health risk, especially if natural processes promote PCB volatilization and subsequent exposure to humans. Biodegradation of PCBs would reduce the risk of adverse human health effects, but this process is poorly understood in sediments. The objective of this research is to test the hypothesis that aerobic, PCB-degrading bacteria are present and active in PCB-contaminated sediments from Indiana Harbor. Preliminary studies revealed aerobic PCB biodegradation potential, but additional experiments are needed to determine if PCB-degraders are active in these sediments. An array of experimental approaches, some of which are innovative, involving reverse-transcription (RT)-PCR, real-time RT-PCR, proteomics, and metabolite analysis are proposed.

      Publications:

      Liang Y, Martinez A, Hornbuckle KC, Mattes TE. Potential for polychlorinated biphenyl biodegradation in sediments from the Indiana Harbor and Ship Canal. Int Biodeterior Biodegradation. 2014; 1;89:50-57

    • Project Period: 2008

      Evaluation of Enterococci and Bacteroides Real Time PCR Assays for Measuring Recreational Water Quality in Iowa with a Source Tracking Perspective

      Investigator(s):
      L. DesJardin, and N. Hall, University Hygienic Laboratory, University of Iowa
      Abstract:

      Enterococci are recognized by the U.S. EPA as indicator organisms to assess water quality in fresh and marine waters. Although enterococci are a robust indicator of fecal contamination in marine waters, interpretation of elevated levels in fresh waters is less clear. Because enterococci can originate from plants or sewage, it is important to understand the source of the enterococci as it relates to swimmers’ health. It may be that the species of Enterococcus present, rather than total Enterococcus spp., more accurately indicates the public health risk. This project will evaluate four real-time qPCR methods for enterococci and Bacteriodes and apply these methods to monitor ten Iowa beaches with elevated levels of enterococci and/or E. coli. This study will determine if the rapid total enterococci qPCR method can serve as a surrogate for the standard EPA culture method and if all four rapid tests will be able to track the source of the enterococci.

    • Project Period: 2008

      Evaluation of Adenovirus Real-Time and Conventional PCR Assays to Detect Fecal Contamination in Water and to Identify Its Source

      Investigator(s):
      M. Chorazy and G. Gray,Department of Epidemiology, University of Iowa
      Abstract:

      Fecal contamination of water is a significant public health concern. The primary objective of this proposal is to determine the usefulness of adenovirus as an indicator of fecal contamination and its potential for fecal sourcetracking. This objective will be addressed by the following aims: (1) to improve upon and validate a PCR algorithm to detect human and animal adenoviruses in fecal waste and water, (2) to conduct surveys of adenoviruses in cattle and swine stool in order to determine the usefulness of adenovirus as a source-tracking organism, and (3) to estimate the prevalence of human and animal adenoviruses at impaired and transitional Iowa beaches and to identify parameters associated with adenovirus in surface water. Results from this study will be used to further develop rapid methods to detect adenoviruses in water and accurately identify sources of contamination which would be informative to risk assessment and risk management practices. Technical Report Available.

    • Project Period: 2008

      Transformation and Fate of Manufactured Metal Nanoparticles in Aqueous Environments

      Investigator(s):
      V.Grassian, Department of Chemistry, University of Iowa
      Abstract:

      This study is designed to provide the data needed to predict the environmental fate and human health effects of commercially manufactured nanoparticles in aqueous solution. With the widespread development of nanoscience and nanotechnology, nanoparticles represent a potential emerging contaminant. The main objectives of the research are to determine under what environmental conditions do manufactured metal nanoparticles of different size and composition aggregate in solution and under what conditions do metal nanoparticles dissolve? Complementary studies to investigate the fundamental surface properties and surface chemistry of metal nanoparticles will be done as surface properties control both nanoparticle aggregation and dissolution as well as nanoparticle-biological interactions. These data can then be used to predict the environmental fate of commercial nanoparticles and are important in assessing the human health effects associated with these materials.

    • Project Period: 2008

      Effect of Agricultural Pesticides on Prostate Cancer Progression

      Investigator(s):
      M. Henry, Department of Molecular Physiology and Biophysics and C. Lynch, Department of Epidemiology, University of Iowa
      Abstract:

      The Agricultural Health Study (AHS) associated exposure to certain pesticides with increased prostate cancer risk in individuals with a first-degree family history of prostate cancer. These findings indicate that exposure to these environmental contaminants may interact with a genetic predisposition toward prostate cancer, but the biologic mechanism(s) by which this might occur remain unclear. This information is critical not only for better defining the risks posed by these pesticides for farm workers and others exposed to these chemicals, but also may advance our understanding of prostate cancer progression in the general population. Experimental exploration of the mechanistic links between pesticide exposure and prostate cancer progression will be difficult in humans. Therefore, the objective of this proposal is to test whether exposure to organophosphorothioates accelerates prostate cancer progression in a mouse model genetically predisposed to develop premalignant prostate lesions (B6:PTEN/luc) in order to establish an experimental platform for exploring these links.

      Publications:

      Svensson RU, Haverkamp JM, Thedens DR, Cohen MB, Ratliff TL, Henry M. Slow disease progression in a C57BL/6 Pten-deficient mouse model of prostate cancer. Am J Pathol.2011; 179(1):502-512

    • Project Period: 2007

      Mechanisms of Perfluorooctanesulfonamide- Induced Oxidative Stress in Female Rats

      Investigator(s):
      W. Xie, H. Lehmler, Department of Occupational and Environmental Health, The University of Iowa
      D. Spitz, Department of Radiation Oncology, The University of Iowa
      Abstract:

      Perfluorinated compounds such as perfluorooctanesulfonamides (PFOSAs) are emerging as an important class of environmentally persistent chemicals. Our knowledge of their mechanisms of toxicity is very limited. Exposure to these chemicals has been associated with developmental toxicity in several animal models. Based on the observation that PFOSAs are peroxisome proliferators and cause mitochondrial dysfunction we hypothesize that oral exposure to a typical PFOSA such as N-EtFOSE (N-ethyl perfluorooctanesulfonamidoethanol) may cause oxidative stress in vivo. We will test this hypothesis by measuring markers of oxidative stress and the activity of enzyme in selected organs. This pilot study will answer important questions regarding the toxicity of PFOSAs and allow us to design further investigations of the mechanisms of their toxicity.

      Publications:

      Xie W, Ludewig G, Wang K, Lehmler HJ; Model and cell membrane partitioning of perfluorooctanesulfonate is independent of the lipid chain length; Colloids Surf B Biointerfaces 2010 Mar1;76(1): 128-36.

      Xie W, Bothun GD, Lehmler HJ; Partitioning of perfluorooctanoate into phosphatidylcholine bilayers is chain length-independent; J Chem Phys Lipids 2010 Mar; 163(3): 300-8.

      Xie W, Kania-Korwel I, Tharappel JC, Telu S, Coleman MC, Glauert HP, Kannan K, Mariappan SVS, Spitz DR, Weydert J, Lehmler HJ; Subacute exposure to N-ethyl perfluorooctanesulfonamidoethanol results in the formation of perfluorooctanesulfonate and alters superoxide dismutase activity in female rats; Arch Toxicol 2009; 83:909-924.

    • Project Period: 2007

      Determining the Mechanistic Effects of the Physical Properties of Nanocrystalline Zeolites on Cell Toxicity

      Investigator(s):
      A. Salem, Department of Pharmaceutics, S. Larsen, Department of Chemistry, The University of Iowa
      Abstract:

      The rapid growth and development in the synthesis of nanomaterials with carefully controlled properties, such as size and shape, surface area and composition has led to a burgeoning of potential applications for these nanomaterials. However, the toxicological effects of these materials such as nanocrystalline zeolites have not yet been systematically investigated and assessed with respect to their properties. In this proposal, the impact of size, surface chemistry, composition and porosity of nanocrystalline zeolites on the mechanism of death in lung epithelial cells will be investigated.

      Publications:

      Petushkov A, Intra J, Graham JB, Larsen SC, Salem AK; Effect of Crystal Size and Surface Functionalization on the Cytotoxicity of Silicalite-1 Nanoparticles. Chem. Res. Toxicol. 2009; 22:1359-1368.

    • Project Period: 2007

      Arsenic speciation in Iowa's groundwater and surface water

      Investigator(s):
      D. Simmons, University Hygienic Laboratory, University of Iowa
      Abstract:

      Arsenic (As) is a highly regulated trace element due to its adverse health effects. The University Hygienic Laboratory has closely monitored total arsenic concentrations in Iowa's surface (lakes, rivers, streams, etc.) and groundwater; elevated levels of arsenic have been detected in the past. Different As species, including inorganic and organoarsenic species, have different toxicities and bioavailabilities. We propose a pilot study to take an initial assessment of As speciation in both groundwater and surface water from a variety of Iowa sites. A hyphenated technique, coupling Inductively SCoupled Plasma - Mass Spectrometry (ICP-MS) with a liquid chromatographic (LC) separation, will facilitate the analytical tasks. Some water chemistry parameters and their influence on arsenic speciation will also be investigated. Joining with the Iowa Statewide Rural Well Water Survey Phase II (SWRL 2), it is expected that this study will lead to a more comprehensive arsenic environmental chemistry study in the rural environment.

    • Project Period: 2007

      Exploratory Studies of a Novel Pathway for the Formation of halo-organic "Disinfection By-Products"

      Investigator(s):
      R. Valentine, Department of Civil and Environmental Engineering, University of Iowa
      Abstract:

      It is hypothesized that metal oxides may exist in some drinking water distribution systems capable of oxidizing iodide and possibly bromide producing species that can react with natural organic to form halo-organic compounds of possible health concerns. This hypothesis is based on recently obtained experimental evidence indicating that lead oxide (PbO2), an oxide that can accumulate in distribution systems and on household plumbing fixtures, has the capacity to oxidize iodide. The primary objectives of this research are to demonstrate proof-of-concept of this novel reaction pathway, and to investigate factors that influence the extent and rates of the reactions. Studies will initially focus on the lead oxide-iodide-NOM system and measurement of selected iodo-organic compounds. Additional studies will be conducted using several other oxides. If iodide is found reactive, then oxidation of bromide will also be evaluated to determine if formation of bromo-organic compounds is also possible at environmentally relevant conditions.

      Publications:

      Lin YP, Washburn MP, Valentine RL; Reduction of Lead Oxide (PbO2) by Iodide and formation of Iodoform in the PbO2/I-/Nom system. Environ Sci Technol. 2008; 42:2919-2924.

    • Project Period: 2007

      Paraquat-Mediated Generation of Endogenous Neurotoxins Resulting from Dopamine Oxidation

      Investigator(s):
      J. Doorn, Division of Medicinal and Natural Products Chemistry, College of Pharmacy, University of Iowa
      Abstract:

      Exposure to environmental chemicals is a known risk factor for Parkinson's Disease (PD). Specifically, chemicals used in agriculture, (e.g. paraquat), are associated with PD. However, the exact relationship between exposure and disease is not known, and the underlying mechanism remains to be elucidated. Recent evidence suggests oxidative stress, but it is not known how these agents (e.g. paraquat) produce specific death of DA neurons as observed in PD. A potential mechanism may involve DA-derived endogenous neurotoxins, which would be found in DA regions of the brain. In this proposal, it is hypothesized that exposure of brain mitochondria to the herbicide paraquat results in accumulation of oxidized DA, specifically, DOPAL and/or the DA-quinone, yielding protein modification by these reactive compounds. Therefore, the studies described in this application seek to establish a mechanistic link between exposure to paraquat and aberrant levels of neurotoxic DA oxidation products proposed to participate in PD pathogenesis.

    • Project Period: 2006

      The Prevalence and Control of Fragrance Compounds in Iowa Drinking Water

      Investigator(s):
      K. Hornbuckle, W. Wombacher, Department of Civil and Environmental Engineering, University of Iowa
      Abstract:

      The purpose of this pilot project is to evaluate the effectiveness of water treatment in removing fragrance compounds from drinking water. Synthetic musk fragrances are common additives to many household products. They have been found in wastewater effluent discharge and are considered to be common contaminants in surface waters. The effectiveness of conventional water treatment at removing synthetic fragrances is not well known. Some evidence suggests that removal efficiencies are very poor. This is of concern because many synthetic musk fragrances are endocrine disruptors and may present a health risk to humans. The objectives of this pilot project include: 1) Weekly monitoring at the University of Iowa Water Plant: 2) Determination of removal efficiency; and 3) Evaluation of specific treatment processes.

      Publications:

      Wombacher WD, Hornbuckle KC; Synthetic Musk Fragrances in a Conventional Drinking Water Treatment Plant with Lime Softening. J Environ Eng (New York). 2009135(11): 1192-1198.

    • Project Period: 2006

      Polychlorinated Biphenyls are an "Old" Issue:Telomere Toxicity Accelerates Senescence and Promotes Carcinogenesis

      Investigator(s):
      J. Jacobus, Interdisciplinary Degree in Toxicology, G. Ludewig, Department of Occupational and Environmental Health, University of Iowa
      A. Klingelhutz, Department of Microbiology, University of Iowa
      Abstract:

      Polychlorinated Biphenyls (PCBs) are persistent organic pollutants classified as "probable human carcinogens" by the US Environmental Protection Agency. The exact mechanism of PCB carcinogenesis continues to be elusive. This pilot study proposes techniques for the investigation of a novel target of PCB toxicity, the telomere. Telomeres are rapidly being recognized by scientists as key cellular factors in carcinogenesis, cell-signaling, and senescence. Oxidative stress has been shown to shorten telomeres and therefore reduce the protective buffer they provide to the chromosome. Researchers have implicated oxidative stress as the ultimate carcinogen resultant from PCB exposure. However, no study has examined a telomeric toxicity arising from PCB metabolism. Positive findings in this study could open up an entirely new line of innovative interdisciplinary research, while providing a unifying explanation to the often contradictory findings in PCB carcinogenesis.

      Publications:

      Senthilkumar PK, Klingelhutz AJ, Jacobus JA, Lehmler H, Robertson LW, Ludewig G; Airborne Polychlorinated Biphenyls (PCBs) Reduce Telomerase Activity and Shorten Telomere Length in Immortal Human Skin Keratinocytes (HaCat). Toxicol Lett. 2011; 204(1):64-70.

    • Project Period: 2006

      Development of a Single Particle Analysis Technique for Real-Time Monitoring and Characterization of Bioaerosols

      Investigator(s):
      M. Young, Department of Chemistry, University of Iowa
      Abstract:

      We propose to develop an advanced instrument capable of determining the aerodynamic size, approximate shape, and detailed chemical composition of single bioaerosol particles sampled directly from the ambient atmosphere. The correlated data will be used to classify individual particles and provide a detailed characterization of diverse aerosol populations. Sample preparation will be minimal and the analysis sufficiently rapid that identification can be achieved in near real-time. The experimental methodology will integrate advanced solid-state laser sources and mass spectrometric techniques to fashion a powerful and unique instrument. The resultant device will be used in projects to characterize bioaerosols present in the environment, such as in agricultural workplaces, provide a sensitive detection capability for possible biohazards, and monitor bioaerosol transformations induced by chemical processing in the atmosphere. The capabilities of the proposed instrumentation would greatly facilitate epidemiological studies which seek to correlate bioaerosol exposure with deleterious health effects. Technical Report Available.

    • Project Period: 2006

      Mouse Model of Experimental Asthma Using (1->3)-->-B-D- Glucan Derivatives

      Investigator(s):
      N. Metwali, P. Thorne, Department of Occupational and Environmental Health, University of Iowa
      Abstract:

      Animal models that mimic the pulmonary features observed in human asthma are important tools to study the mechanism(s) of allergen-induced asthma. (1->3)-B-D-Glucans are fungal cell wall polysaccharides that stimulate innate immune responses and are responsible for bioaerosol-induced respiratory symptoms in both indoor and occupational environments. We propose to examine the interaction between different types of glucan (branched and linear) in C3HeB/FeJ mice. We propose exposure of groups of mice to curdlan as a linear (1->3) glucan, pustulan as a linear (1->6) glucan and scleroglucan and laminarin as (1->3)(1->6) branched glucans. This study will bring new understanding to the role of glucans with differing tertiary structure in the induction of inflammation and specific immunity.

    • Project Period: 2006

      Demonstration Project for Source-Receptor Modeling of Vehicular Toxic Gases and Particles

      Investigator(s):
      C. Stanier, Department of Chemical and Biochemical Engineering, University of Iowa
      Abstract:

      This proposal describes the development of a personal exposure screening tool for prediction of gas- and aerosol-phase vehicular air toxics. The tool will marry existing approaches for gaseous pollutants together with emerging techniques and data for size-resolved fine, ultrafine, and nanoscale particulate matter (mainly from diesel exhaust). Including size-resolved particulate matter in a screening model is a significant challenge, made necessary because of the recent focus on the relationships between traffic, health effects, and ultrafine/nanoparticle toxicity. Further rationale for including size resolution comes from upcoming EPA-mandated changes to diesel sources. Emphasis will be placed on creating an efficient model for general and screening use, rather than a highly detailed model for application to a specific location or exposure setting. It is anticipated that the work product will be well received by funding agencies, public health researchers, and transportation planners.

    • Project Period: 2005

      White-tailed Deer, Mosquitoes, and the Ecology of West Nile Virus

      Investigator(s):
      J. Gill, K. Rainwater, University Hygienic Laboratory, University of Iowa
      Abstract:

      The rapid spread of West Nile Virus (WNV) in the United States has emphasized public health officials concerns about emergent zoonotic diseases. As deer populations continually expand in neighborhoods and areas of significant human activity, Iowans are at an increased risk of several zoonotic infections. We propose a pilot study of over one thousand white-tailed deer (WTD) and several thousand mosquitoes 1) to determine exposure of WTD to WNV, 2) to investigate whether WTD serve as a competent, peri-domestic reservoir for WNV, and 3) to determine anthropophilic mosquitoes that serve as bridge vectors to humans. Serologic testing of deer sera, identification of mosquito host blood, and testing of mosquitoes by polymerase chain reaction will be performed to document risk of Iowans to potential WNV infection. We believe these results will lead to improved surveillance, prevention, and control methods of WNV infections in humans.

    • Project Period: 2005

      Passive Sampling of Ambient Air Particulate Matter

      Investigator(s):
      T. Peters, D.Ott, Department of Occupational and Environmental Health, University of Iowa
      Abstract:

      Adverse health outcomes have been associated with exposure to atmospheric particulate matter (PM). National Ambient Air Quality Standards aim to protect Americans from these exposures through state-run monitoring networks; states must reduce particle concentrations when they exceed national standards. Costs associated with traditional samplers severely limit the number of monitoring sites, which hampers efforts to identify and control key sources of particles. The work proposed here will adapt a new passive sampler for its use in PM networks via three tasks: [i] design an outdoor housing for the new sampler; [ii] assess its precision and accuracy for concentrations typical of the atmosphere; and [iii] use these samplers to identify any key sources of particulate within Iowa City. Passive samplers are substantially more economical than traditional samplers; thus, this work will enable more observations so that actions taken by states to reduce particle concentrations will have a greater likelihood of success.  

      Publications:

      Ott DK, Kumar N, Peters TM. Passive sampling to capture spatial variability in PM 10-2.5 Atmospheric Environment 2007, doi:10.1016/j.atmosenv.2007.09.058

    • Project Period: 2005

      Development of molecular techniques for the detection of vinyl chloride degrading bacteria in the environment

      Investigator(s):
      T. Mattes, Department of Civil and Environmental Engineering, University of Iowa
      Abstract:

      Vinyl chloride (VC), a known human carcinogen, neurotoxin and common groundwater contaminant, represents a serious threat to public health if VC contaminates drinking water source zones. The presence and activity of VC-degrading bacteria at a contaminated site is a crucial line of evidence for demonstrating natural attenuation and a subsequent reduction of risk to human health. Because VC-degrading bacteria appear to be a specialized, non-ubiquitous subset of the ubiquitous ethene-degrading bacteria, there is currently no sequence-based method to distinguish an ethene-degrading bacterium from a VC-degrading bacterium. This is a serious shortcoming for site assessment and bioremediation studies. To alleviate this shortcoming and enhance our ability to compete for external research support, we propose to sequence VC and ethene biodegradation genes from several VC-degrading and solely ethene-degrading bacteria. This work will generate a gene database to facilitate molecular probe design and will shed light on possible VC acclimation mechanisms.         

      Publications:

      Jin YO, Mattes TE. Adaptation of aerobic, ethene-assimilating Mycobacterium strains to vinyl chloride as a growth substrate. ES&T 2008 42:4784-4789.

    • Project Period: 2005

      Adsorption of Environmental Pollutants Using Nanocrystalline Zeolites

      Investigator(s):
      S. Larsen, Department of Chemistry, University of Iowa
      Abstract:

      Zeolites are crystalline, aluminosilicate molecular sieves with pores of molecular dimensions that are widely used as catalysts, adsorbents and ion exchangers. Nanocrystalline zeolites are synthetic zeolites with discrete, uniform crystals of less than 100 nm in size. Nanocrystalline zeolites have increased surface areas relative to commercial, micron-sized zeolites. In our laboratory, we have synthesized several different zeolites (ZSM-5, Y and silicalite) with crystal sizes of approximately 20 nm. These materials have enhanced adsorption capacities due to the increased surface areas relative to micron-sized zeolites. The nanocrystalline zeolite external surface can be functionalized to tailor its properties for adsorption of pollutants in different environments. The hypothesis of the proposed study is that nanocrystalline zeolites will be effective adsorbents for volatile organic compounds (formaldehyde, benzene and trichloroethylene) and inorganic oxyanions (chromate, arsenate, selenate). These environmental pollutants have been linked to many health problems due to their toxicity.   

      Publications:

      Petushkov A, Intra J, Graham JB, Larsen SC, Salem AK. Effect of crystal size and surface functionalization on the cytotoxicity of silicalite-1 nanoparticles. Chem Res Toxicol. 2009 22(7):1359-68.

    • Project Period: 2004

      New Approach to Environmental Immunotoxicant Biomonitoring in Humans: Deoxynivalenol (Vomitoxin) as Example

      Investigator(s):
      S. Hendrich, C. Landgren, Department of Food Science and Human Nutrition, Iowa State University
      Abstract:

      Deoxynivalenol (DON) is the most common fungal contaminant in the human food supply. DON contaminates staple grains (wheat, corn, barley, oats). DON's potential as an agent of biochemical terrorism (it is easy to produce; grain supplies are insecure) also make it a good model for developing environmental human biomonitoring assays. Preliminary data support that this toxin is immunotoxic in vivo and in vitro in concentrations relevant to typical dietary exposures. Research will utilize an assay the PIs have developed to model a simple screening test for environmental immunotoxicants, based on suppression of lymphocyte proliferation in a human cell line. To develop this model, the following unknown effects will be assessed: 1) major DON metabolites on DON immunotoxicity from human plasma samples by synthesizing and testing this metabolite in an assay, and 2) interindividual variation of in human plasma immunotoxic responses due to endogenous or other exogenous factors by assessing the effects of DON-free human plasma assay.

      Publications:

      Landgren CA, Hendrich S, Kohut ML; Low-level dietary deoxynivalenol and acute exercise stress result in immunotoxicity in BALB/c mice; J Immunotoxicol. 2006; 3(4):173-178

    • Project Period: 2004

      Plant-Assisted Bacterial Degradation of Perchlorate

      Investigator(s):
      G. Parkin, J Schnoor, C Just, G Struckhoff, Department of Civil and Environmental Engineering, University of Iowa
      Abstract:

      Perchlorate has been linked with thyroid dysfunction in humans and thus represents a serious potential health risk. Prior research on perchlorate remediation has shown that (1) perchlorate-degrading bacteria are present in nature but are often electron donor limited; (2) plants release electron donors and carbon sources into soil; (3) perchlorate-degrading bacteria require low redox potential to reduce perchlorate; and (4) plants raise redox potential in the subsurface. These findings are somewhat contradictory and may impact perchlorate remediation schemes. We propose to study the relationship between plants and bacteria to determine whether the integrated effect of plants on bacteria is synergistic or antagonistic, whether the release of electron donor and carbon by plants is sufficient to overcome the inhibition to bacterial perchlorate reduction caused by the higher redox potential. Our focus is on higher concentrations of perchlorate (>25mg/L) because we believe it is important to control contamination at its source to effectively reduce health risks.

      Publications:

      Shrout JD, Struckhoff GC, Parkin GF, Schnoor JL; Stimulation and molecular characterization of bacterial perchlorate degradation by plant-produced electron donors.Environ Sci Technol. 2006; 40(1): 310-317

    • Project Period: 2004

      Development of a Passive Air Sampler for Measuring PCBs in Air

      Investigator(s):
      K. Hornbuckle, Department of Civil and Environmental Engineering, University of Iowa
      Hans-Joachim Lehmler, Department of Occupational and Environmental Health, University of Iowa
      Abstract:

      Sampling PCBs in air using high volume air samples is expensive, time consuming, and difficult to implement over a region. This pilot project will build and deploy an inexpensive passive air sampling system for atmospheric PCBs. The major benefit to using passive air samplers is their cost and ease in deployment. The major disadvantage is the lack of quantitative results. Thus, the goal of this project is two fold. First, the concentration of PCBs will be compared using the passive sampler to the concentration of PCBs using high volume samplers side by side. The second goal of this project is to compare the congener distributions of PCBs in air as collected by the passive sampler and a high volume sampler. PCBs are a mixture of as many as 209 different compounds (congeners). The complexity of these mixtures is a result of either the original manufacturing process or of weathering of these compounds in the environment. Several metabolites can be formed from each congener in plants, animals and humans, thus increasing the number of potentially environmentally and biologically relevant PCB compounds that may be present in the environment. This study using the passive samplers will be a good way to examine differences in congener distributions cheaply and effectively.

    • Project Period: 2004

      Are Iowans Exposed to Wild Ducks, Geese, and Game Birds at Risk of Avian Influenza Infections?

      Investigator(s):
      J. Gill, University Hygienic Laboratory, G. Gray, Sharon Setterquist, College of Public Health, University of Iowa
      Abstract:

      The recent explosive epidemic of avian influenza in Asia has many public health officials concerned. Iowans have numerous occupational and recreational exposures to avian species that might cause them to be infected with avian influenza viruses, yet they have never been studied. We propose a pilot seroprevalence study of 250 Iowans with exposure to ducks, geese, and game birds to investigate such transmission. After informed consent is obtained, DNR workers, hunters, and others with game bird exposure will be asked to complete a risk factor questionnaire, and to permit the collection of at least one serum sample. We will also collect cloacal or tracheal samples from 390 of their birds. Human serological testing and bird viral cultures will be performed to document Iowans at high risk of avian influenza virus infection. Identifying high-risk individuals and their exposures is a first step towards developing public health interventions to protect against such future infections.

      Publications:

      Gill J, Webby R, Gilchrist M, Gray G; Avian influenza among waterfowl hunters and wildlife professionals. Emerg Infect Dis ; 2006; 12(8):1284-1286

    • Project Period: 2004

      Sensitivity and reliability of ELISPOT assays for detection of cellular immune responses under simulated field collection

      Investigator(s):
      E. Field, Department of Internal Medicine, University of Iowa
      Abstract:

      There is a need for epidemiology studies examining the role of cellular immune response to environmental risk factors in autoimmunity. These studies will require the development of assays of cell-mediated immunity to assess exposure and immune response to candidate environmental pathogens/xenobiotics. Nearly all of the immune monitoring of field-collected samples consists of assay of humoral immune response. Assays of cellular immune response, of which the lymphocyte proliferation of T cell assay (LPT) is most utilized, have been difficult to adapt to the field. The ELISPOT (enzyme-linked immunosorbant spot) assay is an alternative method to examine T cell immune response in vitro. The proposal examines the hypothesis that the ELISPOT is a more sensitive and reliable assay for evaluating T cell immune response to environmental factors than the standard LPT assay. Furthermore, the proposal seeks to develop ELISPOT to detect cellular immune response to human heat shock protein for future epidemiological studies.

    • Project Period: 2003

      Are Iowa's Meat Processing Workers at Increased Risk of Zoonotic Infections?

      Investigator(s):
      K Myers and G Gray, Department of Epidemiology, The University of Iowa
      Abstract:

      Meat processing workers are often exposed to various avian, swine, and bovine tissues. It is hypothesized that due to these exposures meat processing workers may have elevated risks for acquiring a number of zoonotic infections. This pilot investigation will focus upon three organisms: West Nile virus, influenza A virus, and avian pneumovirus. The study design involves the collaboration of two meat (pork, turkey, chicken, and beef) processing plants in Iowa. One hundred meat processing employees from each site along with their spouses (n~400 subjects) will be enrolled. Serum would be studied for evidence of infection with the three viral agents of interest. Seroprevalence data from the workers at the two plants will be compared with their spouses to discern evidence of occupational risk. This pilot study may shed significant light upon previously unexamined environmental health risks for meat processing workers in Iowa and throughout the United States.

      Publications:

      Meyers K, Olsen C, Setterquist S, Capuano A, Donham K, Thacker E, Merchant J, Gray G; Are swine workers in the United States at increased risk of infection with zoonotic influenza virus? ; Clin Infect Dis. 2006; 42(1):14-20

    • Project Period: 2003

      Heartland Environmental Metal Dental Study

      Investigator(s):
      R Field, Department of Epidemiology and Department of Occupational and Environmental Health, The University of Iowa
      L. Fuortes, Department of Occupational & Environmental Health, The University of Iowa
      B Smith, Department of Biostatistics, The University of Iowa
      L Snetselaar, Department of Epidemiology, The University of Iowa
      D Simmons, The University of Iowa Hygienic Laboratory
      Abstract:

      Few methods accurately assess past exposures, particularly to a variety of toxicants at the same time. The availability of the inductively coupled plasma - mass spectrometer has opened the door to such possibilities. However, most human tissues (blood, urine, hair) generally only reflect rather recent exposure. This study proposes to monitor a variety of metals in a tissue (teeth) that can incorporate metals over an extended period of time. Third molars were chosen for this pilot study for several reasons: 1) they are readily available from a cross-section of young adults in Iowa, 2) they have a relatively large mass as compared to other teeth, which provides greater source material for analysis, and 3) they are the last teeth to be formed, thus potentially reflecting the subjects' environmental exposure to a larger degree than teeth that were formed in utero. This biomonitoring project provides a direct connection between potential environmental toxicants and the human receptor.

    • Project Period: 2003

      Disposition and Metabolism of N-Methyl Perfluorooctane Sulfonamidoethanol (NMeFOSE) in Rats

      Investigator(s):
      H Lehmler, Department of Occupational and Environmental Health, The University of Iowa
      K Hornbuckle, Department of Civil and Environmental Engineering, The University of Iowa
      Abstract:

      Perfluorinated surfactants such as N-methyl perfluorooctane sulfonamidoethanol (NMeFOSE) are produced for a large number of applications such as fire fighting foams and furniture coatings. These chemicals are emerging as an important class of environmentally persistent chemicals. Our knowledge of their metabolism, distribution, disposition and, ultimately, mechanisms of toxicity is very limited. Exposure to these chemicals has been associated with developmental toxicity in several animal models. This research hypothesizes is that after uptake with the diet, NMeFOSE is metabolized in vivo to perfluorooctane sulfonic acid. Studies aims are (1) to synthesize putative perfluorooctane sulfonyl metabolites (2) establish analytical assays to measure NMeFOSE and its metabolites in biological samples, (3) study the in vitro metabolism of NMeFOSE with rat liver microsomes, and (4) measure the distribution of NMeFOSE and its metabolites in female rats.

      Publications:

      Lehmler H, Bummer P; Mixing of perfluorinated carboxylic acids with dipalmitoylphosphatidylcholine. Biochimi Biophys Acta. 2004; 1664(2):141-149

    • Project Period: 2003

      Additive Effects of Environmental Contaminants (Chemical Mixtures) on Selenium-dependent Glutathione Peroxidase

      Investigator(s):
      G Ludewig, L Robertson, Department of Occupational and Environmental Health, The University of Iowa
      Abstract:

      Awareness of environmental contamination and possible health consequences have grown significantly and resulted in increased efforts to monitor and understand the effects of individual compounds. However, this research does not reflect the reality that we are routinely exposed to a variety of environmental contaminants, ranging from metals to industrial compounds. Many environmental chemicals influence the same endpoint, namely the selenium-dependent glutathione peroxidase (Se-GPx), although the chemicals have different chemical structures and mechanisms of toxicity. This proposal addresses the issue of chemical mixtures and is supported by recent papers suggesting a connection between selenium and/or Se-GPx and chemical carcinogenesis. This research will investigate the effects of combinations of environmental chemicals on Se-GPx by employing cell culture and in vivo experiments.

    • Project Period: 2003

      Fate and significance of a veterinary antibiotic in the environment: a laboratory study

      Investigator(s):
      J Coats, T Phillips, J Belden, K Henderson Department of Entomology, Iowa State University
      T Moorman, National Soil Tilth Laboratory, U.S. Department of Agriculture
      Abstract:

      Tylosin is a veterinary antibiotic commonly used in swine production for growth promotion and disease prevention. Swine excrete this drug in urine and feces, and tylosin enters the environment via manure application. This study proposes to investigate the mobility and degradation of tylosin, as well as the survival and movement of microorganisms in the presence of tylosin. Waters leaching from intact soil columns will be examined for tylosin, for total Escherichia coli and for tylosin-resistant E. coli. Following the completion of the study, soil will be evaluated for the mobility of tylosin and presence of metabolites, as well as for survival and movement of microorganisms. The experimental design will allow us to determine if tylosin causes increased levels of tylosin-resistant E. coli in soil or if tylosin increases survival and movement of tylosin-resistant E. coli in manure.

    • Project Period: 2002

      Uptake and Metabolism of Acetanilide Herbicides by Hybrid Poplar Trees

      Investigator(s):
      C Just and J Schnoor, Department of Civil and Environmental Engineering, The University of Iowa
      M Wichman and J Vargo, The University Hygienic Laboratory, The University of Iowa
      Abstract:

      Phytoremediation is the use of vegetation for in-situ treatment of contaminated soils, sediments and groundwater. Hybrid poplar trees have shown the ability to tolerate and metabolize many organic chemicals that have been assimilated into plant tissues through the roots. High-volume acetanilide herbicide use in the Midwest has resulted in both point source and non-point source contamination of shallow groundwater and surface waters. Engineered planting of hybrid poplar trees may be able to intercept and treat herbicide contaminated ground water. Laboratory studies involving hydroponic microcosms and isotopically labeled herbicides will determine plant toxicity and fate pathways for various herbicide mixtures. Mass balances will be completed and the identities of metabolites will be determined using a variety of analytical techniques. The project will test the efficacy of hybrid poplar tree use to remediate contaminated agrichemical facilities.

      Publications:

      Mezzari M, Walters K, JelÕnkova M, Shih M, Just C and Schnoor J; Gene expression and microscopic analysis of arabidopsis exposed to chloroacetanilide herbicides and explosive compounds: a phytoremediation approach. Plant Physiology. 2005;138(2):858-869

    • Project Period: 2002

      Exploratory Studies of Nitroso Compound Formation and Occurrence as a New Class of Disinfectant By-products in Drinking Water and Wastewater

      Investigator(s):
      RL Valentine, Department of Civil and Environmental Engineering, The University of Iowa
      Abstract:

      Until recently it was believed that the occurrence of nitroso compounds in drinking water and wastewater was due to contamination of the source water. Recent observations indicate that N-nitrosodimethylamine (NDMA), a particularly potent carcinogen, can be produced during water and wastewater treatment. Studies at Iowa have recently elucidated a novel formation pathway that involves reactions of chlorine, ammonia, and dimethylamine that support the hypothesis that NDMA is a new disinfectant by-product (DBP). We propose that NDMA is but one representative of a new class of disinfectant by-products, the nitroso compounds, many of which are of health concern. We hypothesize that other types of nitroso compounds are also formed by a similar mechanism in chlorinated and chloraminated drinking and waster. This project will investigate the formation mechanism and occurrence of several nitroso compounds (not NDMA). This information is important in making comprehensive risk assessments of disinfection practices.

      Publications:

      Choi J, Valentine RL. A kinetic model of N-nitrosodimethylamine (NDMS) formation during water chlorination/chloramination. Water Sci Technol. 2002 46(3):65-71 

      Choi J, Valentine RL. N-nitrosodimethylamine formation by free-chlorine-enhanced nitrosation of dimethylamine. Environ Sci Technol. 2003 37(21):4871-76.

      Choi J, Duirk SE, Valentine RL. Mechanistic studies of N-nitrosodimethlamine (NDMA) formation in chlorinated drinking water. J Environ Monit 2002 4(2):249-52.

    • Project Period: 2002

      Pollutants of Emerging Concern in Iowa Air

      Investigator(s):
      KC Hornbuckle, Department of Civil and Environmental Engineering, The University of Iowa
      Abstract:

      Atmospheric deposition of persistent organic pollutants (POPs) to agricultural crops is an important process in human exposure to POPs through the food chain. In order to quantify potential human exposure to these compounds, atmospheric monitoring is necessary. More than 100 air samples will be analyzed for trace level concentrations of potentially hazardous air pollutants of emerging concern. Analytical methods will be designed and tested for flame retardants, oil additives, current use pesticides, fragrance materials, plasticizers, and veterinary pharmaceuticals at trace levels in ambient air. The results of this study will be used to examine fate and transport of these pollutants in air, deposition and accumulation in crops; and risks to human and animal inhalation and ingestion.

      Publications:

      Hornbuckle K, Green M; The impact of an urban-industrial region on the magnitude and variability of persistent organic pollutant deposition to Lake Michigan. AMBIO. 2003; 32(6):406-411

    • Project Period: 2002

      The Fate of Metolachlor, Atrazine, and Pendimethalin During Phytoremediation with Prairie Grasses

      Investigator(s):
      JB Belden, TA Phillips, JR Coats, Department of Entomology, Iowa State University
      Abstract:

      Prairie grasses are currently being used as biofiltration agents in removing pesticides from surface runoff and have been proposed as possible agents useful for phytoremediation of pesticide-contaminated soil. However, little research has been conducted on the fate of herbicides in prairie grass-soil environments. This study proposes to investigate the fate of metolachlor, atrazine, and pendimethalin in soil that has been planted with prairie grasses. Grasses grown in soil fortified with a radiolabeled herbicide will be placed in a sealed acrylic chamber. Volatile organic metabolites and CO2 will be analyzed throughout the experiment. In addition, plant and soil will be analyzed for total radioactivity, parent compounds and major metabolites after a remediation period. The proposed study will enhance our knowledge of the likelihood of the release of herbicides or possible bioactive metabolites back into the environment during and after biofiltration or phytoremediation. Additionally, insight will be obtained into the mechanisms of remediation, including the role of the plant.

      Publications:

      Belden J, T. Phillips T, Coats J; Effect of prairie grass on the dissipation, movement, and bioavailability of selected herbicides in prepared soil columns. Environ Toxicol Chem. 2004; 23(4):125-132

    • Project Period: 2002

      Cephalosporin Resistant E. coli in Iowa Waterways

      Investigator(s):
      PL Winokur, M.D., Department of Internal Medicine, University of Iowa
      Abstract:

      Little is known about the environmental contamination risks associated with agricultural uses of antibiotics or the risks for spread of resistant organisms from agricultural sites to humans. Cephalosporin resistant CMY-2 E. coli have been identified in food animals and humans from Iowa. Preliminary studies suggest that waterborne transfer may play a role in transmission of this resistance. Sixty Iowa surface waterways will be sampled monthly and E. coli expressing CMY-2 will be identified. The associations between upstream agricultural, water treatment or industrial facilities and the effects of rainfall, temperature and stream flow will be analyzed. Sites repeatedly contaminated with CMY-2 E.coli will be intensively studied to pinpoint possible sites of contamination. Candidate contaminating facilities will be identified, and ground water, fecal waste and soil contamination will be analyzed. Studies will utilize microbiology, molecular epidemiology and molecular analyses to understand the epidemiology of CMY-2 E. coli in surface waterways.

    • Project Period: 2001

      Assessment of Low-level Hydrogen Sulfide Exposure among Wastewater Treatment Workers

      Investigator(s):
      SJ Reynolds, Department of Occupational and Environmental Health, The University of Iowa
      JC Johnson, Environmental Health Systems, Iowa City, Iowa
      Abstract:

      Hydrogen sulfide (H2S) is a toxic gas generated in significant quantities from a variety of industrial processes, including wastewater treatment. Acute exposures to high levels of H2S (> 1000 ppm) have been fatal in many instances. Conflicting and sometimes inconclusive studies regarding the health effects associated with low level (<20 ppm) chronic exposure to H2S have led to increased interest in H2S both as an occupational and an ambient air pollutant. Very limited quantitative data exist on the longer-term low-level H2S exposures likely to be encountered everyday by workers in the wastewater treatment industry. By characterizing H2S exposures during specific tasks in four large and four smaller waste treatment facilities over an extended period, the study will collect information needed to conduct future risk assessments or epidemiological studies in order to characterize the health risks, if any, that may be involved in exposure to low concentrations of hydrogen sulfide. The study will also identify factors associated with potential high-level exposures.

      Publications:

      Lee A, Johnson J, Reynolds S, Thorne P, O'Shaughnessy P; Indoor and outdoor air quality assessment of four wastewater treatment plants. J Occup Environ Hyg. 2005; 3(1):36-43

    • Project Period: 2001

      Emission Estimation, Measurement, and Modeling of Ambient Ammonia Concentrations

      Investigator(s):
      PT O'Shaughnessy, KJ Donham, Department of Occupational and Environmental Health, The University of Iowa
      G Carmichael, Department of Chemical and Biochemical Engineering, The University of Iowa
      Abstract:

      The profusion of swine confinements in Iowa has led to many areas in Iowa where local populations are continuously exposed to atmospheric ammonia, and other gases, generated by these facilities. The research for this pilot grant will center on collecting the data necessary for the development of ammonia-emission and dispersion models to determine the levels of ammonia in the vicinity of swine confinements. For this, sensitive analytical instruments are needed to measure the low levels (<1 ppm) of ammonia expected in the atmosphere. Studies will be conducted to establish the accuracy of several ammonia sampling instruments in the laboratory prior to application in the field. Field work will also include the sampling required to estimate ammonia emissions from a working swine confinement. A box model and plume dispersion model will be developed to relate emissions to expected ambient concentrations. Future work will then involve the development of a sophisticated three-dimensional combined meteorological and ammonia exposure model to estimate ambient ammonia given the various chemical reactions ammonia undergoes in the atmosphere.

    • Project Period: 2000

      Reactivity of Disinfection By-Products with Distribution System Pipe Deposits and Cast Iron

      Investigator(s):
      R Valentine, M Scherer, Department of Civil and Environmental Engineering, University of Iowa
      Abstract:

      This project will investigate reactions that could potentially reduce Disinfection By-Products (DBPs) in distribution systems. The researchers hypothesize that the dominant abiotic loss pathways involve reactions with pipe deposit material and with nascent cast iron, especially under reduced conditions. The objective of this research is to characterize the reactivity of selected DBPs with model and collected pipe deposit material, and with cast iron. A special emphasis will be on reactions with unidentified organic halide containing compounds, referred to as unidentified Total Organic Halogen uTOX. This material generally accounts for over 75% of the total halogen incorporated into organic matter.

      Publications:

      Vikesland PJ, Valentine RL; Iron oxide surface-catalyzed oxidation of ferrous iron by monochloramine: implications of oxide type and carbonate on reactivity. Environ Sci Technol. 2002; 36(3):512-519

    • Project Period: 2000

      Changes in Rhizosphere Microbial Populations and Arsenic Speciation as a Result of Phytoremediation of Contaminated Soils

      Investigator(s):
      J Simeonsson, Department of Chemistry, P Alverez, Department of Civil and Environmental Engineering, The University of Iowa
      Abstract:

      This study is designed to evaluate whether the speciation of soil arsenic (As) is altered as a result of phytoremediation and whether microbial communities in the root zone are associated with changes in speciation. It is also of interest to determine whether microbial communities are associated with the volatilization of As compounds. Plant growth experiments will be conducted in controlled environments. Poplar saplings will be grown while exposed to varying amounts of soil-based As. Changes in speciation and volatilization will be investigated through measurements of As in soil, plant and air samples collected from the test chambers. Microbial populations in the rhizosphere of the saplings will be enumerated based on their ability to change the speciation of soil As.

    • Project Period: 2000

      The Role of Surface Precipitates in Remediation Technologies Based on Iron Metal

      Investigator(s):
      M Scherer, Department of Civil and Environmental Engineering, The University of Iowa
      Abstract:

      Recent work on remediation of oxidized chemicals with permeable reactive barriers (PRBs) containing iron metal (Fe0) has shown that remediation performance is strongly affected by the layers of precipitates that form on the iron surface over time, and that the quantity and composition of these precipitates vary greatly depending on the composition of the groundwater. Despite the enormous success of Fe0 PRBs, the identity and significance of this surface precipitate is still unclear. This research proposes to develop a series of experimental protocols to characterize the composition of the surface precipitates forming in the Fe0 PRBs and evaluate how variations in solution chemistry are linked to changes in the precipitate coatings, which then enhance or inhibit PRB performance.

      Publications:

      Alowitz MJ, Scherer MM; Kinetics of nitrate, nitrite, and CR(VI) reduction by iron metal. Environ Sci Technol. 2002; 36(3):299-306

    • Project Period: 2000

      Exploratory and Experimental GIS Studies of the Association of Rural Ambient Air Quality with Asthmatic Children of a Small Area Cohort

      Investigator(s):
      G Rushton, E Svendsen, Department of Geography, The University of Iowa
      P Thorne, Department of Occupational and Environmental Health, The University of Iowa
      Abstract:

      Ambient air pollution sources are one of the potential environmental exposure sources that have been suggested to influence childhood asthma. Though asthma research has been done in many cities, little is known about asthma risk factors in rural populations. This study will both explore and experiment on the distributions of asthma cases and controls from the Keokuk County Rural Health Study in the context of neighboring point source air polluters such as hog-lots and grain mills. Space, time, space-time interaction, space-time clustering, and spatial regression analyses will be performed using recently developed spatial statistical tools. The hypothesis will be tested that asthma cases are found to be significantly closer to point source air polluters within the Keokuk Country area than the control group.

    • Project Period: 2000

      Enhancing Bioaerosol Exposure Assessment: A Comparison of Three Commercially Available Impingers Investigators

      Investigator(s):
      T Pearce, P Thorne, Department of Occupational and Environmental Health, The University of Iowa
      Abstract:

      Currently there are no definitions of acceptable exposure or enforceable standards to hazardous bioaerosols that are associated with a high burden of morbidity and mortality. Emerging airborne diseases intensifies the importance of improving methodology for bioaerosol exposure assessment. Improvements will require characterizing the capabilities and limitations of existing methodology and the development of new techniques. Impinger samplers hold promise for current assessments, as they possess high collection efficiency and sample analysis flexibility. The study seeks to characterize the collection efficiencies of three commercially available impinger samplers using culture based and non-culture based methods of analysis. Information and data generated is intended to advance bioaerosol assessment in the present and improve methodology in the future.

    • Project Period: 2000

      Comparison of Biological and Chemical Endpoints for Evaluating the Success of Phytoremediation of Pesticide-Contaminated Soil

      Investigator(s):
      J Coats, J Belden, Department of Entomology Pesticide Toxicology Laboratory, Iowa State University
      Abstract:

      The study will evaluate several biological and chemical endpoints as possible indicators of remediation success as compared to traditional chemical analysis. Endpoints to be evaluated will include: chemical analysis of body residues in exposed earthworms, toxicity of soil to lettuce (germination and growth), toxicity of aqueous soils extractions to Daphnia magna, chemical analysis of aqueous soil extractions, toxicity of soil column leachate to D. magna, chemical analysis of soil column leachate, and analysis of soil by rigorous solvent extraction. The proposed endpoints will provide measurements of terrestrial and aquatic toxicity along with thorough evaluation of the pesticides leaching potential. At the end of the study, a better understanding of how phytoremediation may affect bioavailability and the presence of toxic metabolites will be gained.

      Publications:

      Henderson KL, Belden JB, Zhao S, Coats JR; Phytoremediation of Pesticide Wastes in Soil. Z Naturforsch C. 2006; 61(3-4):213-221

    • Project Period: 2000

      Characteristics of BTEX Plumes in Iowa: A survey of Plume Dimensions and Stability

      Investigator(s):
      PJ Alvarez, Department of Civil and Environmental Engineering, The University of Iowa
      Abstract:

      Groundwater contamination by petroleum product releases is a common threat to public health. Contaminant plume dimensions and stability are important to characterize for risk management because they determine the area of influence and the potential duration of exposure. This project will analyze data from about 600 sites to identify central tendencies, variability, and regional trends of hydrocarbon plume characteristics. The data will be obtained from the Iowa Department of Natural Resources electronic database. Statistical analysis will be conducted to answer important questions, such as: What is a typical 'safe' distance down gradient of the source, beyond the reach of the plume? Technical Report Available.

    • Project Period: 1999

      Evaluation of an Assay for Environmental Estrogens in Effluents from Iowa Wastewater Treatment Facilities

      Investigator(s):
      R Summerfelt, Department of Animal Ecology, E Farrar, Department of Zoology, Iowa State University
      Abstract:

      This study hypothesizes that sewage treatment lagoons of Iowa towns contain levels of estrogenic substances that are sufficient to cause endocrine disruption in fish when they discharge to streams. Effluents of municipal wastewater treatment facilities contain alkylphenol polyethoxylates (APEs), which degrade to products that act as estrogen mimics, as well as ethynylestradiol. In this study, blood samples of caged fish held in lagoons will be examined for the presence of a specific blood protein, vitellogenin (VTG), which is normally produced by females. VTG is a biomarker of endocrine disruption when it is found in elevated concentration in female fish and present in the blood of male fish. Quantitative techniques will be developed to assess the level of VTG being produced by the fish.

      Publications:

      Bringolf RB, Summerfelt RC; Reduction of estrogenic activity of municipal wastewater by aerated lagoon treatment facilities. Environ Toxicol Chem. 2003; 22 (1):77-83

    • Project Period: 1999

      Parental Pesticide Exposure and Pregnancy Outcomes Phase I: Evaluation of Self-Reports of Pregnancy History Information

      Investigator(s):
      PA Romitti, CF Lynch, Department of Preventive Medicine and Environmental Health, The University of Iowa
      Abstract:

      This study will evaluate the quality of self-reports of pregnancy history information provided by female spouses enrolled in the Agricultural Health Study (AHS), a prospective cohort study of the occurrence of chronic disease among pesticide applicators and their spouses. Spouse self reports of pregnancy history information will be compared to those constructed from vital record data. Findings from this study will provide insights into the quality of pregnancy history information available in the AHS and preliminary data for future proposals.

    • Project Period: 1999

      Development of Laboratory Techniques for the Study of Heterogeneous Chemistry of Environmental Contamination on Mineral Aerosol

      Investigator(s):
      PD Kleiber, Department of Physics and Astronomy, The University of Iowa
      Abstract:

      The objective of this work is to develop new laboratory techniques for the study of heterogeneous processes involving environmental contaminants on mineral aerosol particle surfaces (such as wind blown soil) under conditions of temperature, pressure, and relative humidity appropriate to the troposphere and surface boundary layer. New laboratory strategies are needed to quantify the chemistry and physical transport process of aerosol particles under atmospheric conditions, and to investigate how these processes affect the fate of key environmental contaminants.

      Publications:

      Prince A, Wade J, Grassian V, Kleiber P, Young M; Heterogeneous reactions of soot aerosols with nitrogen dioxide and nitric acid: atmospheric chamber and Knudsen cell studies. Atmospheric Environment. 2002; 36

    • Project Period: 1999

      Residential Radon Decay Product Exposure and Lung Cancer: The Use of a Novel Radon Progeny Device to Improve Dose Estimates

      Investigator(s):
      RW Field, Department of Preventive Medicine and Environmental Health, The University of Iowa
      DJ Steck, Department of Physics, St. John's University
      Abstract:

      Radon decay product (progeny) produces lung cancer in underground miners, yet epidemiologic studies examining residential radon gas exposure and lung cancer has yielded inconclusive results, raising the issue of whether residential radon progeny exposure poses a significant health risk. Radon decay products and not the radon gas itself deliver the radiological significant doses to the lungs, thus exposure risks need to measure actual radon progeny concentrations. This study proposes to update lung cancer risk estimates previously used in the Iowa Radon Lung Cancer Study using radon progeny dose measurement.

      Publications:

      Field RW, Steck DJ, Smith BJ, Brus CP, Fisher EL, Neuberger JS, Platz CE, Robinson RA, Woolson RF, Lynch CF; Residential Radon Gas Expusre and Lung Cancer: the Iowa Radon Lung Cancer Study. Am J Epidemiol. 2000; 151(11):1091-1102

      Field RW, Smith BJ, Steck DJ, Lynch CF; Residential radon exposure and lung cancer: variation in risk estimates using alternative exposure scenarios. J Expo Anal Environ Epidemiol. 2002; 12(3):197-203

    • Project Period: 1998

      Swine hepatitis E virus contamination of surface water: A possible zoonotic risk

      Investigator(s):
      SJ Naides, Department of Internal Medicine, MR Gilchrist, University Hygienic Laboratory, The University of Iowa
      Abstract:

      Human hepatitis E virus (HEV) is a zoonotic infection that can be passed from swine and rodents to humans. A swine HEV-like virus has been shown to be endemic in swine herds in the Midwestern United States. Recently, the first human case of HEV infection acquired in the United States has been identified; the isolate demonstrated sequence homology closer to swine HEV than to known human HEV isolates. There is increasing public concern about the risks of waste products of intense hog farming operations. The long term goal of this project is a better understanding of the role of animal reservoirs in human infectious diseases, how humans are exposed to animal viruses, and the ability of animal viruses to be transmitted through the environment to humans. The specific goal of this project is to develop an epidemiologic model of environmental cross-species transmission of swine HEV infection.

      Publications:

      Karetnyi YV, Gilchrist MJ, Naides SJ; Hepatitis E virus infection prevalence among selected populations in Iowa. J Clinical Virology. 1999; 14(1):51-55

    • Project Period: 1998

      Prevalence and environmental risk factors for pediatric asthma

      Investigator(s):
      RB Wallace, Department of Internal Medicine and Preventive Medicine and Environmental Health, The University of Iowa
      BC Chrischilles, LJ Fuortes, KT Phillips, Department of Preventive Medicine and Environmental Health, The University of Iowa
      Abstract:

      Bronchial asthma is a common clinical problem in the United States, affecting about 10 million people, or about 4% of the population. The occurrence of childhood asthma has increased in frequency, severity and rate of admisssion to hospitals in the U.S. This is in part due to greater recognition of asthma by families and health care professionals, but also appears to represent a true increase in disease, likely due to increased environmental pollution and allergens. This proposal outlines the first effort to identify prevalence, geographic distribution and seasonal patterns of childhood asthma using an asthma registry which is being initiated in Iowa. Rates of specific treatments will be calculated, based upon health care claims from three major insurers in Iowa. Secondary data representing environmental, climatological, socioeconomic and other patient factors will be analyzed to characterize their influence upon the prevalence and severity of childhood asthma in Iowa communities.

    • Project Period: 1998

      Evaluation of solanesol as a tracer for environmental tobacco smoke

      Investigator(s):
      SJ Reynolds, C Achutan, W Groves, Department of Preventive Medicine and Environmental Health, The University of Iowa
      Abstract:

      The health risks to smokers from inhaling mainstream cigarette smoke are well know. In addition, there is growing evidence of risks posed to the health of non-smokers due to involuntary (passive) inhalation of Environmental Tobacco Smoke. However, epidemiological studies that investigate the relationship between ETS and health effects are seriously hindered for lack of a specific and sensitive tracer for ETS. The goals of this pilot project are to evaluate the use of solanesol as a suitable tracer for ETS in various indoor settings and compare it to nicotine, a widely used specific but not sensitive tracer for ETS.

    • Project Period: 1998

      Effects of bacterial DNA on expression of hypersensitivity pneumonitis

      Investigator(s):
      G Hunninghake, Department of Internal Medicine, The University of Iowa
      Abstract:

      The goal of these studies is to determine the role of bacterial DNA in the development of Hypersensitivity Pneumonitis (HP), an environmental lung disease caused by contamination of hay by thermophilic bacteria. Previous studies have shown that Th1 responses with activation of Interleukin-12 are important in HP. Studies have shown that bacterial DNA is a powerful inducer of IL-12. The role of bacterial DNA in triggering the inflammatory response of HP is not known. To study this, a murine model of HP will be used, where mice will be intranasally installed with thermophilic bacteria. Groups of mice will be treated with thermophilic bacteria that have had the DNA destroyed and compared to groups treated with bacteria with intact DNA. The inflammatory response will be evaluated with histopathology, lung lavage cellarity and lung index. Cytokine responses will be evaluated in lung preparations. Less inflammatory and cytokine responses are expected in mice where DNA has been destroyed.

    • Project Period: 1998

      Analysis of volatile organic contaminants in drinking water using a surface- acoustic wave microsensor

      Investigator(s):
      W Groves, Department of Preventive Medicine and Environmental Health, The University of Iowa
      Abstract:

      Exposure to volatile organic chemicals (VOCs) in drinking water has been linked to a number of adverse health effects including cancer, liver, and kidney damage. However, the large number of potential contaminants and the cost and complexity of existing analytical methods limits the extent to which water quality is routinely characterized. This project focuses on the development and evaluation of an instrument for field analysis of VOCs in drinking water. The instrument will be based on an array of six polymer-coated surface-acoustic-wave microsensors. A test set consisting of dichloromethane, chloroform, 1,1,1-trichloroethane, perchloroethylene, and m-xylene will be used in a series of experiments designed to: 1) select and optimize the preconcentration system; 2) calibrate the instrument over the concentration range of 0.2-2 times the EPA Maximum Contaminant Level (MCL); and 3) compare results to those of a recognized laboratory. The primary goal is to develop a cost-effective alternative for on-site evaluation of VOCs in water.

      Publications:

      Groves WA, Grey AB, O'Shaugnessy PT; Surface accoustic wave (SAW) microsensor array for measuring VOCs in drinking water. J Eniviron Monit. 2006; 8(9):932-941

    • Project Period: 1997

      Respiratory health effects of soybean fungal bioaerosols

      Investigator(s):
      PS Thorne, CJ Roy, Department of Preventive Medicine and Environmental Health, The University of Iowa
      Abstract:

      Exposures to grain dust aerosols in agricultural work environments have been linked to a variety of respiratory diseases, including occupational asthma, chronic bronchitis, and hypersensitivity pneumonitis. Agricultural workers are exposed daily to grain dust through combining, grain handling, mixing of feeds, or grain processing operations. Soybeans, which account for 1/4 of the crop value in Iowa, have been damaged increasingly by Sclerotinia sclerotiorum or "white mold", a fungal pathogen. There has been an increase in health complaints of Iowa soybean farmers following exposure to white mold as the proportion of the soybean crop infected with the mold has increased. Yang (1997) reported a doubling in the extent of white mold infestation since 1995. This project will investigate the respiratory health effects of exposure to S. Sclerotiorum and other soybean bioaerosols through inhalation toxicology studies using established animal models.

      Publications:

      Roy CJ, Thorne PS; Exposure to particulates, microorganisms, beta(1-3) -glucans, and endotoxins during soybean harvesting. AIHA J (Fairfax, Va.) 2003; 64(4):487-95

    • Project Period: 1997

      Measuring low level arsenic exposure through drinking water

      Investigator(s):
      JB Simeonsson, Department of Chemistry and Center for Global and Regional Environmental Research, The University of Iowa
      Abstract:

      A major limitation to assessing the health related impact of environmental arsenic (As) is the inadequacy of current analytical methods, especially in regards to providing speciation information of environmental As compounds. The lack of information on speciation is problematic as it is well known that different As species have considerable differences in bioavailability, toxicity and presumably in carcinogenicity. The primary objective of this project is to develop analytical procedures suitable for characterizing and speciating low levels of As in drinking water and biological fluid samples. Ultra sensitive laser induced fluorescence (LIF) approaches will be developed to measure ultra trace levels of As in various sample matrices. These studies will establish the efficacy of the LIF approach and demonstrate its utility for characterizing very low levels of As species in a variety of sample materials.

      Publications:

      Pacquette HL, Elwood SA, Ezer M, Swart DJ, Simeonsson JB; Hydride generation laser-induced fluorescence of arsenic and selenium in the inductively coupled plasma and electrothermal atomizer. Applied Spectroscopy. 2000; 54(1): 89-93

      Swart DJ, Simeonsson JB; Development of an electrothermal atomization laser excited atomic fluorescence spectrometry procedure for direct measurements of arsenic in diluted serum. Analytical Chemistry. 1999; 71(21): 4951-4955

    • Project Period: 1997

      A geographic information systems approach for assessing the impacts of chemical hazards on vulnerable populations

      Investigator(s):
      MP Armstrong, J Chakraborty, Department of Geography, The University of Iowa
      Abstract:

      Advances in technology have created a multitude of airborne hazards that can affect the health and welfare of the population. Airborne toxic releases occur rapidly and the dispersed hazardous chemicals often present immediate acute health effects. The objective of this research is to develop a practical, workable approach for assessing the population at risk to accidents involving airborne toxic hazards. Methods based on the application of geographic information system (GIS) technology will be developed to achieve this goal. A particular emphasis will be placed on the identification of vulnerable population groups, including institutions (e.g., schools and hospitals) and their relationship to locations of potential hazardous material generation sites. In addition to integrating the key components of hazard analysis, the study will also extend and implement a new approach, known as geographic plume analysis, that accounts for directional biases in the distribution of hazards by using a chemical dispersion model to identify the area that is likely to be exposed to airborne toxic releases. Cedar Rapids, IA, will be used as a test-bed for developing these procedures.

      Publications:

      Chakraborty J, Armstrong M; Assessing the Impact of Airborne Toxic Releases on Populations with Special Needs. Professional Geographer. 2001; 53(1)

    • Project Period: 1997

      Exploratory studies of an innovative reactor system for the destruction of organic contaminants in water

      Investigator(s):
      RL Valentine, Department of Civil and Environmental Engineering, The University of Iowa
      Abstract:

      A need exists for improved methods to destroy organic contaminants in drinking water, industrial waste waters, and to remediate contaminated aquifers. Advanced oxidation technologies, which involve the formation of highly reactive hydroxyl radicals, are an emerging class of technologies finding increasing use to treat a variety of these contaminated waters. Application of currently available processes are limited, however, because they require relatively expensive components, have high operating costs, involve complex reactor configurations and process control, and require a relatively high level of training to operate. A need exists for a simple and inexpensive method of oxidizing contaminants using hydroxyl radicals. Recent work at The University of Iowa has resulted in an improved understanding of the reaction mechanism describing hydrogen peroxide decomposition in the presence of iron coated media, and realization of how to possibly exploit this in an innovative fixed-bed reactor system for the destruction of organic contaminants. This project will evaluate the application of this reactor system to oxidize selected contaminants under a variety of reaction conditions, and will gather preliminary design information of use in estimating its capabilities, limitations, and costs.

    • Project Period: 1997

      Investigating the presence, levels, and fate of aflatoxin B1 in soil and aerosolized soil dust

      Investigator(s):
      MI Selim, JM Starr, Department of Preventive Medicine and Environmental Health, The University of Iowa
      Abstract:

      The presence of aflatoxin B1 in agricultural soil poses a potential health risk to farmers from exposure to aerosolized soil dust during plowing and cultivation activities. In addition, aflatoxin B1 may constitute a health risk through contamination of surface water or groundwater. The primary purpose of this project is to investigate the presence and concentrations of aflatoxin B1 in Iowa. Supercritical fluid extraction (SFE), flow injection renewable surface immunoassay (FIRSI) with fluorescence detection, and HPLC/ES/MS methods will be developed and used for the determination of aflatoxin B1 and its transformation products in soil. This study will provide needed data to support external funding of a more detailed regional investigation of the fate and potential health risk of aflatoxin B1, as well as potential control and detoxification mechanisms.

      Publications:

      Selim M, Juchems A, Popendorf W; Assessing Airoborne Aflatoxin B1 during on-farm grain handling activities. American Industrial Hygiene Assocation Journal. 1998; 59(4):252-256

      Starr JM, Selim MI; Supercritical fluid extraction of aflatoxin B(1) from soil. J Chromatogr A. 2008; 1209(1-2):37-43

    • Project Period: 1997

      Climate effects on human health in Iowa: Preliminary assessment of health implications of climate change

      Investigator(s):
      GR Carmichael, Department of Chemical and Biochemical Engineering, The University of Iowa
      Abstract:

      This project will perform a preliminary assessment of climate effects on human health in Iowa. A database will be compiled which consists of a historical fifty year record of daily meteorological factors (temperature, relative humidity, etc.) consisting of one site per county, along with meteorological quantities predicted for future climates based on Global Climate Model (GCM) results. Basic health-related weather quantities will be derived (heat stress index), and will be made available for studies relating weather attributes to morbidity and mortality. The data set will then be used in a preliminary assessment of the future risks associated with climate change. This will be accomplished by combining this data set with population and health-related statistics (hospital admissions, deaths by disease/cause, etc.)

      Publications:

      Carmichal G, Folk G, Schnoor J; Preparing for global change: a midwest perspective.Climatic Change. 1997; 37(6):1

    • Project Period: 1997

      Bioaugmentation of the poplar rhizosphere with genetically engineered microorganisms

      Investigator(s):
      PJ Alvarez, JL Schnoor, Department of Civil and Environmental Engineering, The University of Iowa
      Abstract:

      Phytoremediation, the use of plants to remove environmental pollutants, holds great promise to reduce health risks associated with groundwater and soil contamination. Poplar trees can enhance site remediation by vegetative uptake of the contaminant or by enhancing its microbial degradation in the rhizosphere. This latter mechanism is not very effective for removing nitroaromatic contaminants. This project will evaluate the potential for a nitroaromatic-degrading, genetically-engineered microorganism (E. Coli DH5 [pDTG800]) to enhance bioremediation of 2,4,6-trinitrotoluene (TNT) in the poplar rhizosphere. The fate of both 14C-labeled TNT and E. Coli DH5 [pDTG800] will be studied in soil and plant bioreactors. The hypotheses are that 1) bioaugmentation of the poplar rhizosphere with this clone will enhance the mineralization of TNT; and 2) the added clone will maintain its nitroaromatic degradation activity and survive for a longer period of time in soil rhizosphere compared to background (control) soil. This research may lead to a better understanding and a more widespread acceptance of bioremediation in the rhizosphere as an additional tool for reducing health risks associated with environmental pollution.

      Publications:

      Jordahl J, Foster L, Schnoor J, Alvarez P; Effect of hybrid poplar trees on microbial populations important to hazardous waste bioremediation. Environ Toxicol Chem. 1997; 16(6):1318-1321

    • Project Period: 1996

      The toxicity of 2,4,6-trinitrotoluene (TNT) and its metabolites to Populus sp.

      Investigator(s):
      JL Schnoor, PL Thompson, Department of Civil and Environmental Engineering, The University of Iowa
      Abstract:

      This research will study the phytoremediation of 2,4,6-trinitrotoluene (TNT) ammunition wastes using hybrid poplar trees. Studies will concentrate on phytoremediation using Imperial Carolina (Populus deltoides nigra DN-34) for terrestrial/uplands treatment of TNT wastes, by investigating the phytotoxicity of TNT and its two primary metabolites 2-amino 4,6-dinitrotoluene (2A) and 4-amino 2,6-dinitrotoluene (4A). These treatability studies will lead to preliminary design calculations for TNT contaminated soil and groundwater treatment systems. In particular, the results of this research will help assess the impact of poplar hybrids at an Iowa Superfund site located at Middletown, Iowa.

      Publications:

      Thompson P, Ramer L, Schnoor JL; Uptake and Transformation of TNT by Hybrid Poplar Trees. Environmental Science & Technology. 1998; 32(7):975-980

      Just CL, Schnoor JL; A preperation technique for analysis of explosives in plant tissues.Intl. J. Phytoremediation. 2000; 2(3):255-267

      Yoon JM, Oh BT, Just CL, Schnoor JL; Uptake and Leaching of Octahydro-1,3,5,7-tetranitro-1,3,5,7- tetrazocine by Hybrid Poplar Trees. Environmental Science and Technology. 2002; 36 (21):4649 -4655

    • Project Period: 1996

      Characterization of lead exposure among bridge repair workers

      Investigator(s):
      SJ Reynolds, LJ Fuortes, Department of Preventive Medicine and Environmental Health, The University of Iowa
      Abstract:

      Exposure to lead is now being recognized as a primary health hazard facing construction workers. Of particular concern are those activities that involve the demolition, repair and reconditioning of lead-based painted surfaces, such as bridge repair work, which generate significant airborne lead concentrations. Recently, several workers on a local bridge renovation project were diagnosed as having medical problems associated with overexposure to airborne lead. This overexposure was determined to result from lead dust generated during the operations necessary for bridge renovation: cutting, blasting, scraping, and hammering of painted metal surfaces. More information is needed concerning the fate of lead dust generated during bridge renovation and repair activities. This study will establish baseline data on the lead concentrations found at bridge repair sites, and use this data in exposure assessment and characterization by personal exposure monitoring and sampling during each of the activities involved in bridge repair operations.

      Publications:

      Johnson JC, Reynolds SJ, Fuortes LJ, Clarke WR; Lead exposure among workers renovating a previously de-leaded bridge: comparison of trades, work tasks. AIHAJ: Journal for the Science of Occupational & Environmental Health & Safety. 2000; 61(6):815-819.

      Reynolds SJ, Seem R, Fuortes LJ, Sprince NL, Johnson J, Walkner L, Clarke W, Whitten P; Prevalence of elevated blood leads and exposure to lead in construction trades in Iowa and Illinois. American Journal of Industrial Medicine. 1999; 36(2):307-316

    • Project Period: 1996

      An investigation of the potential use of tree-ring chemistry to record the history of site contamination

      Investigator(s):
      JM Pleasants, Department of Zoology and Genetics, Iowa State University
      M Edelson, Ames Laboratory of U.S. Department of Energy
      Abstract:

      In determining the health risks of a contaminated site it is important to know when the contamination occurred, or began occurring, and when toxic materials became available to the surrounding biota. Trees growing in the vicinity of a contaminated site may provide such a historic record. Chemical contaminants of soil or water may be picked up in the water entering trees and be deposited in their growth rings. The chemical content of individual tree rings can be examined using a new technique. Individual rings are sampled using laser ablation; the ablated material is then analyzed by mass or optical spectrometry. This study will examine the accuracy of using the laser ablation sampling technique and the ability of tree rings to monitor contamination. The first part of the proposed research will involve locating a suitable test site in Iowa and the second part will involve taking core samples of trees and analyzing the material.

    • Project Period: 1996

      Municipal water softening and mortality rates of heart disease in Iowa

      Investigator(s):
      GF Parkin, Department of Civil and Environmental Engineering
      CF Lynch, Department of Preventive Medicine and Environmental Health, The University of Iowa
      Abstract:

      In the United States, hardness (mostly magnesium and calcium) is removed from drinking water to prevent scaling of pipes and consumption of soap. Several studies indicate magnesium and calcium may be protective against heart disease. Removing hardness by ion exchange results in an increase in sodium concentration. Sodium is a well established risk factor for hypertension and resulting ischemic heart disease. An ecologic trends study of community mortality rates of heart disease in Iowa will be conducted to test three hypotheses: 1) mortality rates of heart disease are elevated in communities using ion exchange softening treatment; 2) communities using lime softening treatment have lower mortality rates of heart disease compared to communities using ion exchange; and 3) drinking water hardness may be protective against heart disease. Linkage of existing health outcome and municipal water quality databases maintained by the State Health Registry of Iowa and CHEEC will be a main component of this study. Significant differences in mortality rates of heart disease by type of softening treatments would indicate that more in-depth studies are warranted. Technical Report Available.

    • Project Period: 1996

      Evaluation of pesticide exposure during application and incidental contact with treated areas of turf

      Investigator(s):
      BC Kross, H Nicholson, L Ogilvie, Department of Preventive Medicine and Environmental Health, The University of Iowa
      Abstract:

      Direct exposure to pesticides of persons walking or recreating on lawn and turf areas has become a common concern to the public and the scientific community. Exposures acquired during the application of both agricultural and lawn chemicals have been measured extensively. However, exposure among bystanders and post application entrants in treated areas has been minimal. This study will provide estimates of these exposures by utilizing the Video Imaging Technique for Assessing Exposure (VITAE System). Using fluorescent dye as a surrogate, potential dermal exposures will be quantified through image analysis for applicators and for bystanders, as well. Use of the VITAE System allows for evaluation of potential dermal exposures to a variety of pesticide types and classes.

    • Project Period: 1996

      Pesticides in ambient air and precipitation: Implications for exposure assessment

      Investigator(s):
      GR Hallberg, B Coppage, GM Breuer, D Larrabee-Zierath, University Hygienic Laboratory, The University of Iowa
      Abstract:

      Atmospheric transport and deposition of pesticides are issues of significant concern. The presence of pesticides in rain implicates their presence in air, yet few, if any studies have analyzed ambient air for multiple residues of pesticides currently used. Atmospheric transport may be another important route of exposure to the general public and to sensitive, non-target ecosystems. This study will concurrently determine pesticides in air and rainfall at three sites - one farm, one urban, and one - to initially characterize agricultural and urban effects, and local and regional transport effects. Analytes include the pesticides commonly used in Iowa. A staggered sampling interval will characterize seasonal and temporal changes related to application periods. This project will develop some of the first data on year round ambient air pesticide concentrations. The findings will be the basis for expanded studies of exposure assessment, fate and transport, and non-target ecosystem effects.

    • Project Period: 1996

      Spatial variability of 226 Radium in a water distribution system

      Investigator(s):
      LJ Fuortes, EL Fisher, Department of Preventive Medicine and Environmental Health, The University of Iowa
      Abstract:

      Radium is considered a class A carcinogen by the EPA and Iowa has some of the highest ground water radium concentrations in the U.S. In 1976 the Safe Drinking Water Act (SDWA) set a maximum contaminant level for combined 226Radium and 228Radium at 5 pCi/L. However, the EPA does not specify time or location of sample collection for radionuclides. The Iowa Department of Natural Resources specifies only that the sample be representative of the water distribution system. Epidemiological studies have used 226Radium analyses of samples collected for SDWA compliance as a measure of exposure. However, radium-rich pipe-scale deposits found in water distribution systems are a potential source for radium enrichment of drinking water after it enters the distribution system. The purpose of this pilot study is to determine if dissolution and/or dislodgment of radium from pipe scale significantly increases radium concentrations at the point of use.

       

      Publications:

      Publications:  Fisher EL, Fuortes LJ, Valentine RL, Mehrhoff M, Field RW; Dissolution of 226Radium from pipe-scale deposits in a public water supply. Environment International. 2000; 26(1-2): 69-73

      Fisher EL, Fuortes LJ, Ledolter J, Steck DJ, Field RW; Temporal and spatial variation of waterborne point-of-use 222Rn in three water distribution systems. Health Physics. 1998; 74(2):242-248

    • Project Period: 1996

      A prospective cohort study of municipal drinking water nitrate level and cancer risk: The Iowa Women's Health Study

      Investigator(s):
      JR Cerhan, CF Lynch, BC Kross, Department of Preventive Medicine, The University of Iowa
      W Zheng, A Folsom, School of Public Health, University of Minnesota
      Abstract:

      The increasing contamination of groundwater by nitrate, primarily from the widespread use of commercial fertilizers, is an evolving public health concern in agricultural states. Nitrate can undergo endogenous reduction to nitrite, and nitrosation of nitrites can form N-nitroso compounds, which are potent carcinogens. There are few epidemiologic data, and no prospective cohort data, on whether nitrate exposure from drinking water increases the risk of cancer, in particular cancers of the digestive tract, the urinary tract, and non-Hodgkinlymphoma. This study proposes linking the Iowa WomenHealth Study, a prospective cohort study of cancer in women aged 55 to 69 years in 1986, to historical water quality databases available from CHEEC. Average nitrate exposure from drinking water over a 10 to 20 year window will be related to cancer risk, after adjustment for age, dietary nitrate intake, factors which impact endogenous nitrosation (vitamin C and E intake and smoking), and other site-specific confounders.

      Publications:

      Weyer P, Cerhan J, Kross BC, Hallberg G, Kantamneni J, Breuer G, Jones M, Zheng W, Lynch CF; Municipal Drinking Water Nitrate Level and Cancer Risk in Older Women: The Iowa Women's Health Study. Epidemiology. 2001; 11(3):328-338

    • Project Period: 1996

      Flow cytometric assessment of chromosomal damage induced by environmental contaminants

      Investigator(s):
      SL Berberich, GR Hallberg, MD Wichman, University Hygienic Laboratory, The University of Iowa
      Abstract:

      The health consequences of chronic low concentration exposure to environmental contaminants are not well understood and need continued study. Most toxicological studies use concentrations well above those observed in the environment. This study will use the exceptional sensitivity and discriminatory power of flow cytometric analysis, to detect if chromosomal breakage occurs in cells grown in culture. Another objective is to find out whether the damage results from exposure to common herbicides at concentrations actually found in the environment. The effects of 10 individual herbicides and 2 metabolites will be assessed. Also, additive or synergistic effects from exposure to combinations of herbicides will be identified. These data can provide understanding of the functional basis for some chronic toxicological responses and contribute to other epidemiological and toxicological investigations. After this validation study the methods can be extended to other contaminants and realistic combinations. This work will hopefully lead to development of additional molecular methods for toxicological evaluations pertinent to Iowa.

    • Project Period: 1995

      The use of automated PCR/ELISA technique to detect indicators of fecal contamination

      Investigator(s):
      L Sutton, Department of Pathology; GR Hallberg, University Hygienic Laboratory
      NA Lynch, Department of Preventive Medicine and Environmental Health, The University of Iowa
      Abstract:

      Fecal contamination of water supplies is a major cause of infectious disease with consequences ranging from minor illness to patient death. Current culture-based detection methods are decades old and take days to complete. Once identified, the presence of specific pathogens can take additional time. Clearly, the development of modern methods of detection are imperative. Automated polymerase chain reaction (PCR)-based methods would have major advantages over current procedures. The automation (1) minimizes risks of amplicon contamination and (2) allows for reliable, high throughput analysis. The PCR methodology (1) allows rapid turnaround time of hours instead of days, (2) permits adjustable sensitivity and specificity, (3) enables rapid subsequent analysis of positives samples to identify specific pathogens, and (4) identifies hard to culture pathogens. Such a system would help to minimize exposure to contaminated water sources and, when exposure has occurred, to rapidly guide appropriate antimicrobial chemotherapy, thus reducing morbidity and mortality.

    • Project Period: 1995

      Effect of poplar trees on microbial populations important to hazardous waste bioremediation

      Investigator(s):
      JL Jordahl, LA Licht, PJ Alvarez, Department of Civil and Environmental Engineering, The University of Iowa
      Abstract:

      Phytoremediation, the use of plants to remove pollutants from the environment, holds great promise to reduce health risks associated with groundwater and soil contamination. It is widely recognized as an under utilized technology, and its successful application on a large scale will require continued input from basic research. Poplar trees could enhance site remediation via contaminant uptake and in-plant degradation, by minimizing off-site migration, or by enhancing microbial degradation in the rhizosphere. This project will characterize the microbial community beneath 7-year-old poplar trees. The hypothesis is that poplar roots exert selective pressure for the proliferation of microorganisms important to bioremediation. These include microorganisms capable of removing nitrate by denitrification, as well as microorganisms that can degrade carcinogens such as benzene or atrazine. Most Probable Number (MPN) techniques will be used to characterize and enumerate indigenous microorganisms with such specific traits. Viable plate techniques will be used to assess microbial diversity. Predominant microbial colonies will be isolated and identified using a BIOLOG system. Background soil will also be characterized to serve as a control for the root effect. Such information will contribute to the rational development of phytoremediation.

      Publications:

      Jordahl JL, Foster L, Schnoor JL, Alvarez PJ; Effect of Poplar Trees (Populus spp.) on Microbial Populations Important to Hazardous Waste Bioremediation. Environ Toxicol Chem. 1997; 16(6):1318-1321

    • Project Period: 1995

      Development of an exposure database for nitrate contamination of private drinking-water/groundwater supplies

      Investigator(s):
      GR Hallberg, University Hygienic Laboratory
      KD Rex, Iowa Department of Natural Resources, Geological Survey Bureau, The University of Iowa
      Abstract:

      Nitrate is the most common chemical contaminant in groundwater and drinking water in Iowa. This study will provide a cost-effective method for surveillance of nitrate contamination of private drinking-water supplies that can be used for exposure assessment, epidemiological studies, and monitoring of nitrate contamination over time. The University Hygienic Laboratory database of private well-water analyses (approximately 10,000 nitrate analyses/year) will be related to the Iowa Groundwater Vulnerability Regions (GVR) using the IDNR Geographic Information System. Zip-code areas will be spatially related to the GVR units and then the UHL water-quality data will be summarized by zip-codes, by GVR unit, by well depth, and by year. This will provide a sensitive analytical tool to assess spatial and temporal differences in water quality. It is proposed that this approach be used to develop an annual report of water-quality trends in Iowa, summarizing exposure and resource implications.

    • Project Period: 1995

      Expression of toluene dioxygenase under various redox and substrate conditions

      Investigator(s):
      NA Lynch, Department of Preventive Medicine and Environmental Health, The University of Iowa
      PJ Alvarez, Department of Civil and Environmental Engineering, The University of Iowa
      Abstract:

      Bioremediation, the enhancement of microbial activity to degrade environmental pollutants within aquifers, show great promise to reduce health risks associated with groundwater contamination. The success of bioremediation, however, can be limited by the availability of electron acceptors (e.g. O2) and by the expression of appropriate catabolic enzymes (e.g. toluene dioxygenase). The dissolved oxygen concentration threshold for the expression of toluene dioxygenase, and the ability of various target contaminants and other substrate to induce this enzyme will be investigated. Toluene dioxygenase is an ideal enzyme for a study of bioremediation because of its ability to catalyze the aerobic biotransformation of a wide variety of ubiquitous priority pollutants, including petroleum hydrocarbons (e.g. benzene, toluene, and xylenes) and solvents (e.g. trichlorethylene). Enzyme expression will be quantified using an enzyme linked immuno sorbent assay (ELISA). This project will enhance understanding of the limitations of catabolic enzyme expression during bioremediation. The identification of non-polluting enzyme inducers could also lead to improved bioremediation of trace pollutants and to the development of better cometabolic processes.

    • Project Period: 1994

      Exploratory studies of the effect corrosion control strategies on radium accumulation in distribution system deposits and radon release into drinking water

      Investigator(s):
      RL Valentine, J Jackson, Department of Civil and Environmental Engineering, The University of Iowa
      Abstract:

      Strategies used to control lead and copper corrosion often produce insoluble surface coatings on distribution system pipes. Changes in overall water chemistry resulting from treatment alterations could have a major impact on the nature of distribution system deposits. Increased incorporation of radium could occur resulting in an increase in radon in the distribution system. This study explored the incorporation of radium into and radon release from deposit material formed when several corrosion control strategies used in water distribution systems are implemented. Phosphate containing coatings and deposits are a concern because phosphate bearing minerals can accumulate large amounts of radium. Of particular interest is determining the radium content of deposits under experimentally difficult conditions where small amounts of deposits are formed and little radium is actually removed from the water, but where the amount of radium per unit mass of deposits could be very high. Experimental results conclude: 1) Radium activity of pure calcium carbonate was much lower than the solid produced when either iron or zinc phosphate was added. The removal mechanism appears to be surface adsorption; 2) Addition of zinc phosphate greatly reduced the quantity of solids produced in the presence of calcium; 3) Radium removed from water when iron was added with zinc phosphate was significantly greater than that obtained with iron only; 4) Presence of calcium reduced radium removal from solution in the presence of iron and greatly increased the mass of deposit formed when phosphate was no present; 5) Percentage of radium removed from solution using orthophosphate in the presence of iron was approximately the same as that obtained using zinc phosphate at comparable dosages as phosphate; 6) Contrary to what might be expected from a cation sorption mechanism, the radium activity per unit mass of solid actually decreased as the pH increased; and 7) Results indicate zinc phosphate in the presence of 160 mg Ca/L and phosphate significantly increased radium accumulation.

      Publications:

      Field RW, Fisher EL, Valentine RL, Kross BC; Radium bearing pipe-scale deposits: implications for national waterborne radon sampling methods. American Journal of Public Health. 1995; 85(4):567-570

      Fisher EL, Fuortes L, Valetine RL, Mehrroff M, Field RW; Dissolution of 225Radium from pipe-scale deposits in a public water supply. Environment International. 2000; 26(1-2):69-73

    • Project Period: 1994

      Development of a database to accommodate management of exposure and environmental data within geographic information system

      Investigator(s):
      US Tim, Department of Agricultural and Biosystems Engineering, Iowa State University
      Abstract:

      A variety of pesticides have been added to the environment to enhance agricultural production and control pests, weeds, and vector-based diseases. The use of pesticides has led to substantial improvements over the past four decades in the quality and variety of the nation's diet. Also, Iowa's economic well being has been enhanced due to the ability to produce crops efficiently, in part due to use of these pesticides. On the negative side, pesticide use in agriculture has led to their detection in drinking water wells in the state. Many of the pesticides are known to be harmful and present health risks. To assess the human health risks posed by pesticides in Iowa's drinking water supplies, information is needed regarding the spatial extent, magnitude of the contamination and exposed population. Much of the available information on pesticide pollution and human health effects is in the form of tabular summaries and spreadsheets. It is important that this information be compiled into a common format in order to make accurate observations and informed decisions. This research project developed a computer-based prototype system, consisting of a database management system and geographic information system, for recording, processing, and displaying spatial, analytical, environmental, and human exposure data collected in Iowa. The various modules of the system allows the user to enter or retrieve data, prepare standard and ad hoc reports, and generate maps for risk analysis and decision making. A prototype was developed and demonstrated, and can be used for environmental health applications.

      Publications:

      Sunday Tim U; The Application of GIS in Environmental Health Sciences: Opportunities and Limitations. Environmental Research. 1995; 71:75-88

    • Project Period: 1994

      Assessment of exposures to bio-aerosols among Midwest farmers - Effects of flooding

      Investigator(s):
      P Thorne, N Lynch, J Lange, J DeKoster, Institute of Agricultural Medicine and Occupational Health, Department of Preventive Medicine and Environmental Health, The University of Iowa
      Abstract:

      Numerous climatic conditions and individual management aspects potentially effect bioaerosol concentrations in agricultural confinement buildings. The unprecedented flooding and heavy summer rainfall of 63.0 cm during 1993 in the state of Iowa provided the opportunity to compare bioaerosol concentrations in dairy barns that used hay and feed grown under wet conditions with bioaerosol concentrations in dairy barns that used hay and feed grown with a normal rainfall of 25.5 cm. Geometric mean time-weighted average viable bioaerosol concentrations in all 40 stanchion dairy barns sampled with an all-glass impinger (AGI) were 2 x 104 cfu/m3 for yeast, 0.9 x 104 cfu/m3 for molds, 80 x 104 cfu/m3 for mesophilic bacteria, and 0.3 x 104 cfu/m3 for thermophilic bacteria. Microorganism concentrations ranged 2-3 orders of magnitude between different barns. Correlation between the variance in microorganism concentrations and climate at time of sampling, ventilation systems, individual management practices, feed type, bed materials, and barn characteristics was assessed. The proportion of variance in microorganism concentrations associated with these variables, as determined by the squared multiple correlation coefficient ranged from 31% to 45%. Important individual variables that correlated with high bioaerosol concentrations were sampling during the distribution of bedding, the use of low storage moisture feeds, and mixing fan type ventilation. Variables that were correlated with low bioaerosol concentrations were tunnel ventilation and the use of high storage moisture feeds. For the 4 classes of microorganisms studied, no correlation (all p0.20) was found with rainfall. Thus, these data refute the common assumption that in-barn use of hay and feed grown under wet conditions leads to significantly higher bioaerosol concentrations. Additional funding to continue research has been provided by the Center for Disease Control, National Institute of Occupational Safety and Health.

      Publications:

      Lange JL, Thorne PS, Kullman GJ; Determinants of viable bioaerosol concentrations in dairy barns. Ann. Agric. Environ. Med. 1997; 4:187-194 

      Lange JL, Thorne PS, Lynch N; Application of flow cytometry and flourescent in situ hybridization for assessment of exposures to airborne bacteria. Appl. Environ. Microbial. 1997; 63(4):1557-1663

      Thorne PS, Lange JL, Bloebaum P, Kullman GJ; Bioaerosol Sampling in Field Studies: Can Samples be Express Mailed? Am. Ind. Hyg. Assoc. 1994; 55:1072-1079

    • Project Period: 1994

      Synthetic soils from industrial wastes, Phase II: Health-related analysis of leachates and crops

      Investigator(s):
      L Drake, M Maxwell, Department of Geology, The University of Iowa
      Abstract:

      The aims of this study were to determine whether bulk municipal and industrial wastes can be blended to create synthetic soils which are not detrimental to human health and which present minimal risks to groundwater quality and natural ecological systems. Such soils could potentially be used to safely reclaim abandoned strip mines. Eighty different blends of synthetic soil were created, and two types of native soils were used as controls. Four annual species of vegetables were grown in pots outdoors utilizing the different soil blends. Experimental results demonstrated that some of the blends of synthetic soil can support good-to-excellent plant growth compared to native soil controls. Quantitative analysis was done on the fruit produced from the plants to assess total weight and total dry weight of the fruit. A follow-up to the study hopes to assess if the longer term responses of perennials to the synthetic soils is similar to short term annuals. Additionally, the ten most promising soils are being leached and evaluated for heavy metals and other parameters relevant to human health.The project has expanded to field scale test plots in an orphan mine in south-central Iowa with additional funding from a National Mine Land Reclamation Center Grant. Cargill Corporation has also agreed to sponsor the project by providing a field test site, machinery, and operators to implement the projects on a field scale.

      Publications:

      Ririe GT, Drake LD, Olson SS(1997); Reclamation and groundwater remediation at a hydrocarbon site in Alaska:Petroleum Hydrocarbons and Organic chemicals In Groundwater Conference. A. Stanley, Editor, National Groundwater Assn., 1997; 266-297.

    • Project Period: 1994

      Air Quality studies and health assessments of individuals living in the vicinity of swine confinement operations

      Investigator(s):
      KJ Donham, KM Thu, PS Thorne, SJ Reynolds, Institute of Agricultural Medicine and Occupational Health, Department of Preventive Medicine and Environmental Health, The University of Iowa
      Abstract:

      This project will provide information on environmental health issues concerning air quality in the vicinity of swine confinement operations in Iowa. The investigation utilizes a questionnaire distributed to residents who live near hog production facilities. The questionnaire measures physical or psychological symptoms associated with nearby hog confinements. Site selection of hog facilities included non-confined hog lots, lagoon/large hog confinements (1000 plus hogs), and medium sized hog confinements with open lagoons. Air samples were taken upwind, downwind, and next to each facility to determine the levels of dust, hydrogen sulfide, and ammonia concentrations present.

      Publications:

      Thu K, Donham KJ, Ziegenhorn R, Reynolds SJ, Thorne PS, Subramanian P, Whitten W, Stookesberry J; A Control Study of Health and Quality of Life of Residents Living in the Vicinity of Large Scale Swine Production. J. Agri. Health and Safety. 1997; 3(1):13-26

      Reynolds SJ, Donham KJ, Stookesberry J, Thorne PS, Subramanian P, Thu K, Whitten P; Air Quality Assessments in the Vicinity of Swine Production Facilities. J. AgroMedicine. 1997; 4:37-45

      Subramanian P, Reynolds SJ, Thorne PS, Donham KJ, Stookesberry J, Thu K; Environmental Assessment of Ammonia in Swine Farming Environment by Enzymatic Fluorimetric Method. Intern. J. Environ. Anal. Chem. 1996; 64:301-312

    • Project Period: 1994

      The use of vegetation to enhance bioremediation of soils in Iowa contaminated with pesticide wastes

      Investigator(s):
      JR Coats, TA Anderson, Pesticide Toxicology Laboratory, Department of Entomology, Iowa State University
      Abstract:

      (This is a continuation of a previously CHEEC funded study on pesticide contamination. See FY 1992.) Evidence for enhanced microbial degradation of xenobiotic chemicals in the rhizosphere, a zone of increased microbial activity at the root-soil interface, continue to accrue, suggesting that vegetation may play an important role in facilitating bioremediation of contaminated surface soils. For sites tainted with pesticide wastes, such as at agrochemical dealerships, establishing vegetation may be problematic because of the presence of herbicide mixtures at concentrations several fold above field application rates. Nonetheless, herbicide-tolerant plants exist that can survive in these environments, and they are ideal candidates for testing the influence of rhizosphere microbial communities on the degradation of pesticide waste. Laboratory experiments have tested whether a commodity plant such as soybeans could survive in soil from a pesticide-contaminated site containing a mixture of three predominant herbicides, atrazine, metolachlor, and trifluraline, and if its presence could enhance biodegradation. Although soybean survival in this soil was high, its presence did not enhance the degradation of the chemicals. Tests with nonvegetated soils and rhizosphere soils from Kochia sp., a herbicide-tolerant plant, showed enhanced degradation of these chemicals in rhizosphere soil. Also, Kochia sp. seedlings have emerged from rhizosphere soils spiked with additional concentrations of the three test chemicals, indicating the ability of these plants to survive in soils containing high concentrations of herbicide mixtures.

      Publications:

      Anderson TA, Kruger EL, Coats JR; Biological Degradation of Pesticide Wastes in the Root Zone of Soils Collected at an Agrochemical Dealership; in Bioremediation through Rhizoshpere Technology. American Chemical Society. 1994; Chapter 16:199-209

      Anderson TA, Kruger EL, Coats JR; Rhizosphere Microbial Communities of Herbicide-Tolerant Plants as Potential Bioremedials of Soils Contaminated with Agrochemicals; in Bioremediation of Pollutants in Soil and Water. American Society for Testing and Materials. 1995; 149-157

      Anderson TA, Coats JR; Screening Rhizosphere Soil Samples for the Ability to Mineralize Elevated Concentrations of Atrazine and Metolachlor. Journal of Science and Health. 1995; B30(4):473-484

      Anderson TA, Kruger EL, Coats JR; Enhanced Degradation of a Mixture of Three Herbicides in the Rhizosphere of a Herbicide-Tolerant Plant. Chemosphere. 1994;28(8):1551-1557

      Anderson TA, Coats JR; The Role of the Rhizosphere in Facilitating Biological Degradation of Hazardous Organic Chemicals; in Bioremediation Science and Technology. Soil Society of America 1995

      Perkovich BS, Anderson TA, Kruger EL, Coats JR; Enhanced Mineralization of 14C-atrazine in Kochia Scoparia Rhizosphere Soil from a Pesticide-Contaminated Site. Pesticide Science. 1996; 46(4):391-396.

    • Project Period: 1993

      A preliminary study of temporal variable of 222Radon in rural community water supplies

      Investigator(s):
      EL Fisher, LJ Fuortes; Department of Preventive Medicine and Environmental Health, The University of Iowa
      Abstract:

      Seasonal and short-term temporal variations of radon suggest that one-time sampling of water supplies may not produce a representative sample of well water. Obtaining concentration levels of water supplies at or near the proposed U.S. EPA Maximum Contaminant Level is complicated by these variations. The aims of this research are to determine temporal variations in 222Radon in community water supplies looking specifically at water use, temperature, precipitation, and barometric pressure; determine the relationship between raw and finished water 222Radon concentrations over time in water supplies where 222Radon in finished water exceeds that in raw water; and propose a sampling scheme which will provide a representative 222Radon water concentration.

       

      Publications:

      Fisher EL, Valentine RL, Kross B; Radium-Bearing Pipe Scale Deposits: Implications for National Waterborne Radon Sampling Methodologies. American Journal of Public Health. 1995; 85:567-570

      Fisher EL, Valentine RL, Kross B; Occupational Exposure of Water Plant Operators to High Concentrations of radon-222 Gas. Journal of Occupational and Environmental Medicine. 1996; 38(8):759-764

      Fisher EL; Temporal and Spatial Variation of Waterborne Point-of-Use radon-222 in Three Water Distribution Systems. Health Physics. 1998; 74(2):242-248

    • Project Period: 1993

      A historical cohort study of cancer among urban vs. rural residents and farmers vs. non-farmers in Iowa

      Investigator(s):
      CF Lynch, H Song, Department of Preventive Medicine and Environmental Health, The University of Iowa
      Abstract:

      The aims of this study were to 1) Calculate and analyze "smoking-related" cancer incidence by urban vs. rural residents and farmers vs. non-farmers for 1977-1992; 2) Calculate and analyze incidence rates for the "farming-related" cancers by farmers vs. non-farmers (only males) for 1977-1992, and 3) Evaluate variations between urban and rural residents and farmers and non-farmers in lifestyle (consumption of tobacco and alcohol). Data were used from two previously conducted population-based case-control studies. These studies were "Case-Control Study of Cancer and Drinking Water Contaminants" and "Iowa Portion of the National Collaborative Bladder Cancer Study". Statistically significant findings include: 1) The percentage of current smokers and ex-smokers in urban areas exceeded those in rural areas, males and females in urban areas smoked more cigarettes and consumed more alcohol on a per day basis, and men smoked more and drank more alcohol per day than females; 2) Urban-rural differences of SIR (total observed events in a population/ total expected events in a population) were significant for smoking related cancers as a group, due in part to higher rates of smoking and drinking in urban residents; 3) The risk of smoking-related cancers was significantly greater in non-farmers than in farmers. Completion of this study demonstrated the feasibility of doing a cohort study by linking multiple, distinct, yet complimentary databases. The resulting database is a unique resource for additional studies of cancer. These results have provided preliminary data to support grant proposals to federal agencies to conduct further investigations.

    • Project Period: 1993

      Comparison of trihalomethanes in residential water using source surface water and indoor air with residential water using source groundwater and indoor air

      Investigator(s):
      SJ May, PA Kostle, GM Breuer, University Hygienic Laboratory, The University of Iowa
      Abstract:

      The purpose of this study was to assess exposure of four trihalomethanes (THMs-chloroform, dichlorobromomethane, dibromochloromethane, and bromoform) in tap water and indoor air. Measurements of tap water and indoor air during and after showering were taken in residential homes. Houses using private well water (non-chlorinated), public groundwater supply (chlorinated), and public surface water sources (chlorinated) were all evaluated in the study. Water and air samples were collected for each event. THM concentration was taken in the tap water during showering, air samples were collected in the bathroom prior to shower, during showering, and a third air sample was collected in the living room area 30 minutes after showering. Results showed highest THMs in public surface supply, followed by the public groundwater supply. No THMs were detected in the private well water. The public groundwater supply was the only water sampled with all four THMs present. In air samples for the public surface water supply, dibromochloromethane and chloroform were detected. During shower air samples showed an increase in THMs, thus indicating volatilization from the water. In the public groundwater supply, chloroform was the most frequently observed THM. The study reports that while THM concentrations within public groundwater supplies tended be low (5 ppb), THMs were consistently present in the air samples in the living room area. For private wells with no chlorination, THMs were not present in the water, nor were they consistently present in air samples. When there was a positive detection in the air, it was attributed to a running dishwasher in the kitchen that used a detergent containing chlorine bleach. This study shows that showerers are exposed to low levels of THMs in the air during a shower and it may be worthwhile to further quantitate effects of water temperature or bathroom ventilation to be able to recommend ways of minimizing exposure. Technical Report Available.

    • Project Period: 1993

      Source of drinking water and cancer incidence in Iowa

      Investigator(s):
      CF Lynch, M Zhang, D Olsen, Department of Preventive Medicine and Environmental Health
      PJ Weyer, KD Sesker, Center for Health Effects of Environmental Contamination, The University of Iowa
      Abstract:

      The potential impacts of exposure to various contaminants in drinking water on cancer incidence have been investigated. This study was an ecological investigation as a follow-up to a previous study that looked at incidence rates and time trends of cancer by source of drinking water and size of municipality in Iowa. Cancer incidence ratios for the 16 most common cancers in Iowa were analyzed by size of municipality, by source of drinking water, and by well depth and aquifer for groundwater sources. Time trends were also evaluated. The following results were found: 1) Male and female lung cancers increased as size of community population increased; 2) There is a significantly higher incidence of female lung cancer in towns population 1,000-10,000 using surface water; 3) For communities using groundwater as their source of drinking water, the study found higher rates of lung cancer and total cancers in females in towns with shallow wells compared to towns using deep wells; and 4) Findings show a significant increase in trend over time for lung cancer in both sexes, regardless of water source or well depth, and show a significant increase in the incidence of male bladder cancer in towns with shallow wells, as well as a significant decease in the incidence of several other types of cancer in groundwater communities at various well depths. This study did not support all the findings of previous studies. In the future, this type of analysis will be conducted on a periodic basis, to continue the mission of CHEEC. Technical Report Available.

    • Project Period: 1993

      Chloramine decomposition product studies

      Investigator(s):
      RL Valentine, M St. Clair, Department of Civil and Environmental Engineering, The University of Iowa
      Abstract:

      Monochloramine (NH2Cl) produced from the reaction of free chlorine and ammonia in a process called chloramination, is generally considered to be a leading candidate as an alternative disinfectant to replace free chlorine which is known to produce a variety of potentially mutagenic and carcinogenic organic by-products. However, while chloramination produces fewer organic byproducts, recent work has shown that at least one unidentified inorganic decomposition product is formed. The existence of an unidentified product should be a cause of concern because of potential health effects. This research focus on the characterization, identification, and quantification of the unknown(s) produced in chloraminated drinking water under a variety of reaction conditions. This will be done by 1) conducting detailed mass balances on chlorine and nitrogen, 2) developing methodology to separate and concentrate the unknown(s), and 3) applying mass spectrometry and NMR techniques to characterize structure. Expanded research is being funded by a grant from AWWARF.

      Publications:

      Ozekin K, Valentine RL, Vikesland PJ; Modeling Chloramine Decay an Natural Waters.American Chemical Society (ACS) Symposium Series 649, Water Disinfection and Natural Organic Matter. 1996; 113-125

      Vikesland PJ, Valentine RL, Ozekin K; Application of Product Studies in the Elucidation of Chloramine Reaction Pathways. American Chemical Society (ACS) Symposium Series 649, Water Disinfection and Natural Organic Matter. 1996; 105-114

      Vikesland PJ, Ozekin K, Valentine RL; Effect of Natural Organic Matter on Monochloramine Decomposition: Pathway Elucidation Through the Use of Mass and Redox Balances. ES&T. 1998; 32(10):1409-1416

    • Project Period: 1992

      The potential use of vegetation for bioremediation of surface soils contaminated with pesticide wastes: Implications for Iowa

      Investigator(s):
      JR Coats, TA Anderson, Pesticide Toxicology Laboratory, Department of Entomology, Iowa State University
      Abstract:

      The purpose of this study was to investigate sites contaminated by pesticides, and determine whether vegetation can have a positive effect on microbial degradation of hazardous compounds in soils as a result of the rhizosphere effect. Enhanced microbial degradation of hazardous chemicals in the rhizosphere suggests that plants could be managed at contaminated sites to facilitate microbial degradation of unwanted organics. Experiments on the influence of vegetation on microbial degradation of pesticides were conducted utilizing nonvegetated and vegetated scenarios in environmental chambers. The study tested degradation of atrazine, metolachlor, and trifluralin using the herbicide resistant plant Kochia sp. Degradation tests with sterile soil, edaphosphere soil, and rhizosphere soil collected from the root zone of Kochia sp. indicated a significantly enhanced microbial degradation of the pesticides. Degradation of the parent compounds was significantly accelerated in the rhizosphere soil. Project continuation see FY 1994.

    • Project Period: 1992

      Comparison of sampling methods for lead in dust

      Investigator(s):
      SJ Reynolds, MI Selim, PS Thorne, Institute of Agricultural Medicine and Occupational Health, Department of Preventive Medicine and Environmental Health, The University of Iowa
      Abstract:

      Understanding the relationship between environmental exposure and blood lead concentration in children has been complicated by the lack of standardized sampling methodology. The specific goal of this project was to evaluate and compare three methods for sampling lead-containing dust on interior surfaces. Lead-containing dust at three different concentrations was generated in a cubic-meter chamber and uniformly deposited onto a variety of surfaces typically found in the home environment (painted wood, unpainted wood, varnished wood, linoleum, and carpet). Surface dust samples were collected using Whatman filter paper #42 wetted with distilled water (OSHA method), commercial wipes with a non-alcohol wetting agent (the wipe method recommended by HUD for dust clearance after lead abatement), and a vacuum filter method using cellulose acetate filters in 35 mm cassettes at a flow rate of 2 Lpm (vacuum method). Results showed on most surfaces (painted wood, unpainted wood, varnished wood and linoleum) the recovery of the HUD method was significantly higher than the vacuum method and the OSHA method. On carpet, the recovery using the vacuum method was significantly higher. For all wipe sampling methods the recovery depends on the surface characteristics.

      Publications:

      Reynolds SJ; Laboratory Comparison of Vacuum, OSHA, and HUD Sampling Methods for Lead in Household Dust. American Industrial Hygiene Association Journal. 1997; 58(6): 439-446

      Etre LA, Reynolds SJ, Burmeister LF, Whitten PS, Gergely R; An evaluation of the effectiveness of lead paint hazard reduction when conducted by homeowners and landlords. Applied Occupational & Environmental Hygiene. 1999; 14(8):522-529

    • Project Period: 1992

      Improving and expanding computerized municipal water supply and water quality data in the state of Iowa

      Investigator(s):
      P VanDorpe, RL Talcott, Iowa Department of Natural Resources-Geological Survey Bureau
      Abstract:

      This project assembled and updated a Well Identification Table (WIT) for Iowa's Municipal Water Supply Inventory (MWSI). The MWSI combines municipal well and water supply data from the Environmental Protection Division of DNR with geological and aquifer data from the Iowa Geological Survey and raw water quality data obtained from the University Hygienic Laboratory and the US Geological Survey. Every municipality and rural water supply in the MWSI has been updated through communication with DNR field offices, consultants, municipalities, and others. Historical and current water quality analyses are linked with information on active and abandoned municipal wells. The WIT will be a dynamic database providing scientists with an interactive system to conduct water-quality research.

    • Project Period: 1992

      Validation of family history obtained through parental interview

      Investigator(s):
      TL Burns, PA Romitti, Department of Preventive Medicine and Environmental Health, The University of Iowa
      Abstract:

      Collection of family history data is important when evaluating environmental and genetic risk factors associated with epidemiologic studies. The aims of this study were to determine the percent concordance between maternal interview responses for family history information and blood relative questionnaire responses, and assess the independent effects of maternal age, education, income, marital status, gravidity, and study group status (case or control) on the validity of family history information provided by maternal interview. The results of the research suggest blood relative birth defect and cancer diagnoses provided by study mothers should be viewed with caution. Sensitivity estimates of maternal responses for blood relative birth defect diagnoses were low for both case and control groups. In contrast, sensitivity estimates of maternal responses for blood relative cancer diagnoses were higher for case mothers than control mothers. No independent factors of maternal age, education, income, marital status, gravidity, and study group status on the sensitivity of maternal telephone interview responses were found to be associated with sensitivity for blood relative birth defect diagnoses. For blood relative cancer diagnoses, analyses suggest that study group status was a significant factor in the determination of sensitivity with control mother reports being less accurate than case mother reports. Results of this study will be used to establish subject recruitment protocol and to design the family history questionnaire for an upcoming multi-state genetic epidemiologic case-control investigation of facial clefts.

      Publications:

      Romitti P, Burns TL; Feasibility of collecting disease reports from relatives for genetic epidemiologic investigations. Human Heredity. 1997; 47(6):351-357

      Romitti P, Burns TL, Murray JC; Maternal interview reports of family history of birth defects: evaluation from a population-based case-control study of orofacial clefts. Am J Med Genet.1997; 12(72): 422-429

    • Project Period: 1992

      The impact of ozone depletion on the flux of ultraviolet radiation in Iowa

      Investigator(s):
      GR Carmichael, KC Krist, Department of Chemical and Biochemical Engineering, Center for Global and Regional Environmental Research, The University of Iowa
      Abstract:

      Anthropogenic emissions of chloroflurocarbons have been associated with the destruction of stratospheric ozone documented over the last decade. Stratospheric ozone depletion was originally associated with the polar regions of the southern hemisphere, but recent data have shown a decline in the total ozone column over a majority of the globe. A downward trend of 0.4-0.8% per year over the last decade has been documented. Such decreases potentially will have negative effects on human health (skin cancer, cataracts, and immunological impacts), and terrestrial plant life, including agricultural products. Measuring ground level ultra-violet radiation, specifically UV-B has proven problematic due to an incomplete global collection system. Measurements in populated areas tended to show no decrease in the total ozone column due to increased amounts of ozone in the troposphere as a result of pollution. This negated decreases of ozone in the stratosphere. Analysis of total ozone measurements in Iowa over the last decade showed significant seasonal downward trends. Surface level ozone concentrations remained relatively constant, while negative trends in the stratospheric ozone continued for this period. Under current negative trends in stratospheric ozone loss and the relatively low ground level pollution Iowa experiences, Iowa is susceptible to ground level radiative increases. During the summer months, total ozone over Iowa is at a minimum. This trend may have significant health impacts. The Department of Energy provided additional funding to continue research.

      Publications:

      Crist KC, Carmichael GR, Kuruvilla J; UV-B Exposure and Atmospheric Ozone Evaluation of Radioactive Flux to Changes in Ambient Ozone Levels. Journal of Hazardous Materials. 1994; 37:527-538

    • Project Period: 1992

      Pilot studies of the possible relationship between intrauterine growth retardation, birth defects, fish kills, and the genotoxic properties of herbicides following plant activation

      Investigator(s):
      EP Isacson, Department of Preventive Medicine and Environmental Health
      WJ Hausler, University Hygienic Laboratory, The University of Iowa
      MJ Plewa, Institute for Environmental Studies, The University of Illinois
      T Jennings, M Mason, Fisheries Bureau, Iowa Department of Natural Resources
      Abstract:

      The purpose of this study was to determine whether plant activated mutagens could be detected and quantitated from drinking water samples obtained from the Rathbun Rural Water Association. Plant activation refers to the process in which a non-mutagenic agent is transformed by biological action of a plant into a mutagen. Water samples collected were fractionated and concentrated with a 0.2 m tangential flow ultrafiltration membrane, then passed through a NA+ charged cation column. Aliquots were taken after the 0.2 m filter and cation exchange to measure DOC adsorption. The sample was then passed through in a series, a polysulfone 30 kDa ultrafiltration membrane, a poly sulfone 1 kDa ultrafiltration membrane, and a polyamide reverse osmosis membrane. A mass balance analysis based on total organic carbon was conducted on the drinking water and each size fraction. Weak positive responses were observed in one 1 kDa retentate and in two reverse osmosis retentates. In all three cases, there was an initial yet weak statistically significant increase in the mutagenicity of the tested samples. The research concluded that concentrated fractions of Lake Rathbun were rather benign. Even after many fold concentration and analysis with highly sensitive Salmonella mutation tester strains, only a weak positive response was observed with two fractions.

    • Project Period: 1991

      Development of a database of environmental exposures among infertile couples

      Investigator(s):
      K Clark, College of Nursing; E Smith, L Fuortes Department of Preventive Medicine and Environmental Health, The University of Iowa
      Abstract:

      This study developed a database of environmental exposures among infertile couples and identified risk factors for infertility including occupational and chemical exposures, medical, sociodemographic and lifestyle factors. The study was enhanced by enlisting a control group of fertile couples. Crude analysis showed farm exposure was adversely associated with overall and primary infertility, but not secondary infertility. Endometriosis and adjusted age were consistent and adversely associated with all types of infertility. Using step-wise logistical regression procedure and adjusting for all variables, women who reported having lived or worked on a farm for at least 6 months remained at significant increased risk for overall and primary infertility.

      Publications:

      Fuortes L, Clark K, Kirchner H, Smith EH; Associations Between Female Infertility and Agricultural Work History. American Journal of Industrial Medicine. 1997; 31(4):445-451

      Smith E, Hammonds-Ehlers M, Clark K, Kirchner H, Fuortes L; Occupational Exposures and Risk of Female Infertility. Journal of Occupational and Environmental Medicine. 1997; 39(2):138-147

    • Project Period: 1991

      Radon and radium release into drinking water from distribution system deposits

      Investigator(s):
      RL Valentine, SW Stearns, Department of Civil and Environmental Engineering, The University of Iowa
      Abstract:

      The purpose of this study was to determine if evidence of radon formation exists in water distribution systems exposed to radium bearing water. The significance of radium bearing deposits in an actual distribution system depends on a number of factors, including radium content of the pipe deposit, the amount and distribution of pipe deposits, the type of deposits, and the time in which a given water volume is in contact with deposits. The study concludes that radon produced in radium-bearing deposits in the distribution system may cause radon to significantly increase in concentration. Even though the source of the deposit within a distribution system may be small in comparison to a geological source and impact only a very small fraction of the population, the importance must be gauged by the proposed maximum contamination level (MCL) of 300 pCi/L. Radon production within the distribution system may cause radon content to exceed the MCL for some users, even if compliance of the point of entry is achieved. The linkage between radium deposition and radon release may need to be considered in the final EPA radionuclide regulations.

      Publications:

      Valentine RL, Stearns SW; Formation of Radon from Water Distribution Systems Deposits. ES&T. 1994; 28(3):534-537

    • Project Period: 1991

      Investigation of pesticides and synthetic organic compounds with adverse reproductive outcomes

      Investigator(s):
      MD Kramer, CF Lynch, Department of Preventive Medicine and Environmental Health, The University of Iowa
      Abstract:

      The potential reproductive effects of long-term, low-dose exposure to chloroform have received little attention despite the known, acute toxicity of high exposures and the widespread occurrence of low concentrations of chloroform in drinking water. The association of waterborne chloroform was studied with low birth weight, prematurity, and intrauterine growth retardation. Cases were not mutually exclusive, but each outcome was analyzed independently. Exposures to chloroform and other trihalomethanes were ecological variables based on maternal residence and 1987 municipal water survey. After adjustment for maternal age, parity, adequacy of prenatal care, marital status , education, and maternal smoking by multiple logistic regression, residence in municipalities where chloroform concentration in water supplies was 10 ug/liter was associated with an increased risk for intrauterine growth retardation. The major limitations of this study involve the ascertainment and classification of exposures to trihalomethanes, including such issues as the imprecision of using aggregate municipal measures for classifying exposures at the level of the individual, the potential misclassification due to residential mobility, and the fluctuation of trihalomethane levels.

      Publications:

      Kramer MD, Lynch CF, Isacson P, Hanson JW; The Association of Waterborne Chloroform with Intrauterine Growth Retardation. Epidemiology. 1992; 3(5):407-413

    • Project Period: 1991

      Building and environmental factors associated with elevated radon levels in rural Iowa homes

      Investigator(s):
      L Fuortes, L Weih, Department of Preventive Medicine and Environmental Health, The University of Iowa
      Abstract:

      The goal of this project was to assess the joint influence of home construction and environmental (soil) characteristics in predicting radon concentration in homes. The first part of this work found the relationship between radon concentration and home construction factors was dependent on location of the radon test in homes. In basements, wall construction and degree of energy efficiency predominated in predicting radon concentration. On upper floors, age of home predominated in predicting radon concentration, with a general decrease in radon concentration with age of home. The second part of the study found texture of the soil on which the home is located was the most important predictor of radon concentration for homes tested in the basements. Precipitation totals in the year preceding the screening test were negatively correlated with radon concentration in homes, but the relationship was only apparent when basement wall type and soil texture was accounted for.

    • Project Period: 1991

      Development of a water quality database to assess the factors associated with low birth weight (LBW) rates and intrauterine growth retardation (IUGR)

      Investigator(s):
      KL Cherryholmes, WJ Hausler, University Hygienic Laboratory
      EP Isacson, Department of Preventive Medicine and Environmental Health, The University of Iowa
      Abstract:

      In order to investigate possible relationships between exposures to water contaminants and the development of birth defects in the Rathbun Lake area, water samples were collected and analyzed and the results linked to incidence rates of adverse health outcomes by community. The University Hygienic Laboratory collected and analyzed water samples from Rathbun Lake, from the Rathbun Regional Water Association water treatment plant, and from various points along the water distribution system to assess the seasonal fluctuation of herbicides, nutrients, and total coliforms. A database containing the results was developed and utilized by CHEEC researchers to continue assessment of factors affecting LBW and IUGR in communities served by the Rathbun Regional Water Association.

    • Project Period: 1991

      A preliminary survey of radon-222, radium-226, and radium-228 in private well-water supplies in Iowa

      Investigator(s):
      RW Field, Department of Preventive Medicine and Environmental Health
      KL Cherryholmes, University Hygienic Laboratory, The University of Iowa
      Abstract:

      This study represents the first statewide random sampling of private water-borne radon-222 in the nation, and also collected information on radium-226 and radium-228. The health risks of water-borne radon-222 are considered high, and the U.S. EPA has proposed a maximum contaminant level (MCL) of 300 pCi/ L for public water supplies. Study findings include: 1) Participant collected samples at the point-of-use are comparable to samples professionally collected; 2) Fifty-two percent of the wells sampled had waterborne radon-222 concentrations that exceeded the proposed MCL; 3) Radon-222 concentrations in private well-water are slightly higher than groundwater supplies. (This is attributed to a higher percentage of private wells drilled into Pleistocene till which often produce higher waterborne radon-222 concentrations, while public supplies are preferentially drilled into alluvial deposit, which generally contain less radon-222 precursor material); 4) The western part of the state has the highest mean radon-222 well-water concentrations as a result of the large number of wells drilled into the Pleistocene; 5) Radon-222 samples did not vary temporally during the one year collection period; 6) The contribution of well-water derived indoor air radon-222 is minimal compared to subsurface soil and rock radon-222 sources in Iowa; and 7) Well depth, well-water radium-226, well-water radium-228, and indoor screening of radon-222 are all extremely poor predictors of well-water radon-222 concentrations. Additionally, because of the huge variations of waterborne radon-222 concentrations noted for the specific aquifer type, their usefulness as a predictor of waterborne radon-222 concentration is limited.

      Publications:

      Field RW, Kross BC; Intercomparison of Waterborne radon-222 Collection Methods: Professional Vs. Homeowner Collection. GWMR. 1996; 16:106-112

    • Project Period: 1991

      Assessment of exposure to bioaerosols in "sick" and "healthy" buildings

      Investigator(s):
      PS Thorne, J DeKoster, Institute of Agricultural Medicine and Occupational Health, Department of Preventive Medicine and Environmental Health, The University of Iowa
      Abstract:

      This study characterized the levels of bioaerosol contamination of indoor air environments. Significant findings of the study include: 1) Fungi and respirable bacteria concentrations were significantly higher in basements, while CO2 levels were higher on the main floor; 2) Healthy homes had indoor viable fungal concentrations 30 to 50% of the outdoor levels, whereas sick homes had levels over 60%. Strong seasonal effect was seen from measurements of outside fungi but this was not reflected in indoor concentrations; 3) CO2 concentration was not associated with bioaerosol concentration; basement relative humidity was associated with increased airborne fungi; central air conditioning and increased air conditioner use were associated with lower microbial concentrations; lower Penicillium and Aspergillus airborne spores were associated with high efficiency furnace filters; and homes with finished basements had significantly lower microbial concentrations; 4) Tests of association using survey results showed age of occupant and the presence of smokers in the house to be significantly associated with increased self-reported health symptoms, including watery eyes, drowsiness, backaches, muscle/joint pain, indigestion, nausea, and flaky skin; and 5) Methodologies using the Anderson microbial sampler and the Burkard spore sampler demonstrated excellent agreement between theses two methods of air sampling.

      Publications:

      DeKoster JA, Thorne PS; Bioaerosol Concentrations in Noncomplaint, Complaint, and Intervention Homes in the Midwest. American Industrial Hygienic Association Journal. 1995; 56:573-580

    • Project Period: 1990

      Analysis of aflatoxins in grain dust

      Investigator(s):
      MI Selim, Institute of Agricultural Medicine and Occupational Health, Department of Preventive Medicine and Environmental Health, The University of Iowa
      Abstract:

      Aflatoxins are recognized as potent chemical carcinogens, have been associated with liver cancer in animal studies, and may be associated with lung cancer incidence in humans exposed to aflatoxins in contaminated grain dust. This project developed and validated a one-step extraction and analysis technique for the separation and quantitative determination of low levels of aflatoxins in airborne grain dust samples. This technique is faster, more sensitive, more selective, and more reliable than present methods. The method is based on the use of supercritical fluid extraction (SFE) on line with gas chromatography or supercritical fluid chromatography followed by mass spectrometric detection (SFE/GC/MS or SFE/SFC/MS). In addition, preliminary data on the levels of aflatoxins in grain dust generated during harvest and on-farm grain handling operations were collected. Results from this study were used to acquire a grant from the National Institute for Occupational Safety and Health to expand research.

      Publications:

      Selim MI, Tsuei MH; The Developement and optimization of a supercritical fluid extraction method for the analysis of aflatoxin B1 in grain dust. American Industrial Hygiene Association Journal. 1993; 54(4):135-41

    • Project Period: 1990

      Investigation of the feasibility of adapting immunoassay tests for detection of minute amounts of pesticides in water

      Investigator(s):
      JM Cowan, SL Berberich, University Hygienic Laboratory, The University of Iowa
      Abstract:

      The aim of this study was to develop a protocol for the detection of the pesticides atrazine and alachlor in water at concentrations below .1 mg/l using immunochemistry. Detection below these concentrations may be useful in identifying trends of increased pesticide contamination before there is a real health risk. The procedure involved using a sample routinely processed for gas chromatograph (GC) analysis and evaluating by immunoassay after evaporating off the solvent and resuspending the sample in water. The study results found immunoassay is only slightly less reliable than GC analysis. Concentrated organic extracts prepared for GC analysis can also be successfully used for the detection and quantitation of atrazine and alachlor by immunoassay analysis at concentrations significantly below the detection limit of GC. Method detection limits for atrazine were calculated at approximately 0.4 ng/l -a 250 fold improvement over GC, and approximately 0.3 ng/l for alachlor- a 300 fold improvement over GC. This procedure is being used in a study investigating the levels of atrazine and alachlor in rain water.

    • Project Period: 1990

      Birth defects in Iowa: Effects of surface water pollution in the Rathbun Lake area

      Investigator(s):
      R Munger, Department of Preventive Medicine and Environmental Health
      JW Hanson, Department of Pediatrics, The University of Iowa
      Abstract:

      The effects of pesticide contamination of drinking water on human reproductive health are largely unknown. In a statewide survey of 856 Iowa municipal drinking water supplies in 1986-1987, a rural water system supplied by the Rathbun Reservoir was found to have elevated levels of the herbicide atrazine, 2.2 mcg/l vs. 0.6 mcg/l in other Iowa surface water supplies. Rates of low birth weights, prematurity, and intrauterine growth retardation (IUGR) in live singleton births during 1984-1990 in women living in 13 communities served by the Rathbun water system were compared to other Iowa communities. The Rathbun communities had a significantly greater risk of IUGR than southern Iowa communities with other surface sources of drinking water. Multiple linear regression analyses revealed that levels of the herbicides atrazine, metolachlor, and cyanazine were each significant predictors of community IUGR rates in southern Iowa after controlling for several potentially confounding factors including maternal smoking and socioeconomic variables. The association with IUGR was strongest for atrazine, but all three herbicides were correlated. The independent contributions of each to IUGR risk could not be determined.

      Publications:

      Munger R, Isacson P, Song Hu, Burns T, Hanson J, Lynch CF, Cherryholmes K, Van Dorpe P, Hausler WJ Jr; Intrauterine Growth Retardation in Iowa Communities with Herbicide-Contaminated Drinking Water Supplies. Environ. Health Perspectives. 1997; 105(3):308-314

    • Project Period: 1990

      Biotransformation and transport of monoaromatic hydrocarbons under stimulated denitrifying conditions in soil columns

      Investigator(s):
      GF Parkin, ME Vermace, Department of Civil and Environmental Engineering, The University of Iowa
      Abstract:

      Leaking underground storage tanks and pipelines are some of the largest contributors to point source contamination of groundwater. The monoaromatic hydrocarbons benzene, ethylbenzene, toluene, and xylene (BETX's) are the hardest to manage if groundwater contamination occurs. This research project examined the role of nitrate as an alternate electron acceptor for biologically mediated reactions important to in situ biorestoration. Batch column study results showed no degradation of benzene, ethylbenzene, nor p-xylene observed over a one-hundred day period. No decrease in nitrate was observed as well. Results from the control reactor suggests that abiotic removal mechanisms such as sorption are negligible. Toluene degradation was observed when fed alone and in the mixture, and a concomitant decrease in nitrate was also observed. The research suggests that the presence of the non degraded BETX's has no apparent affect on the degradation of toluene. Additional research was funded by the Iowa State Water Resources Research Institute.

      Publications:

      Vermace ME, Christianson RF, Parkin GF, Alvarez PJJ; Relationship Between the Concentration of Denitrifers and Pseudomonas spp. in Soils: Implications for BTX Bioremediation. Water Research. 1996; 30:3139-3145

    • Project Period: 1990

      Urban-rural differences in cancer incidence and mortality among Iowa residents

      Investigator(s):
      F Lynch, LF Burmeister, Department of Preventive Medicine and Environmental Health, The University of Iowa
      Abstract:

      Urban-rural differences in cancer incidence and mortality rates were evaluated in a descriptive epidemiologic study among Iowa residents (1973-1988). Results were based on two separate definitions of urban and rural-one county boundary based and the other based on application of an address algorithm. Both definitions yielded similar findings. Two different definitions of mortality were used. The first definition included as an eligible death only those cases where cancer was listed as the underlying cause of death , whereas the second definition included all conditions of cancer where cancer was listed on the death certificate as the underlying cause or as a contributing condition. Study findings were 1) Smoking-related cancers were found to be significantly higher in urban areas relative to rural areas for males and females, and mortality from smoking-related cancers was greater in urban areas; 2) Lip cancer in males was the only cancer site with a significantly elevated rate in rural areas relative to urban areas, all other cancers were higher for urban areas, for both males and females; 3) Better sensitivity was established when using the 'all causes of death' definition, and use of the application algorithm proved more sensitive as well; and 4) Cancer mortality rates were generally higher in those urban and rural areas that had higher cancer incidence rates. An additional research project was funded by the National Cancer Institute to investigate these findings further. Technical Report Available.

    • Project Period: 1990

      Assessment of infant exposure to nitrate/nitrite in breast milk and rural well water

      Investigator(s):
      CI Dungy, LB Dusdieker, Department of Pediatrics
      BC Kross, Department of Preventive Medicine and Environmental Health, The University of Iowa
      Abstract:

      The objectives of this study were to determine if the concentration of nitrate/nitrite in human milk is unsafe for consumption by infants under 6 months of age, and to compare the concentration of nitrate/nitrite in private well-water used as a primary source of drinking water to the concentration of nitrate/nitrite in human breast milk. Participants included 20 women who were either exclusively breast feeding or breast and bottle feeding, and 24 women who were formula feeding. Five of the 20 breast feeders indicated rural well-water as their source of drinking water, and 6 of the 24 formula feeders used private well-water supplies. Three of the eleven wells had nitrate levels greater than the Health Advisory Limit (HAL), but none of these 3 women offered their infants supplemental water or prepared formula using the high nitrate content well-water. Nine of the 20 women who reported exclusive or partial breast feeding had analysis of water, breast milk, and urine samples done. The urine nitrate levels were equal to or up to 69 times greater than the nitrate concentration in breast milk. Analyses of the breast milk indicated in all cases the nitrate concentration was markedly below the HAL.

      Publications:

      Dusdieker D, Stumbo PJ, Kross BC, Dungy CI; Does Increased Nitrate Ingestion Elevate Nitrate Levels in Human Milk? Archives of Pediatrics and Adolescent Medicine. 1996; 150(3):311-314

    • Project Period: 1990

      Development of an immunoassay for the detection of glyphosate in water

      Investigator(s):
      GM Breuer, SL Berberich, University Hygienic Laboratory; The University of Iowa
      Abstract:

      The aim of this study was to develop a monoclonal antibody specific for the common herbicide glyphosate (trade name: Roundup), and develop an immunoassay system for the rapid detection of glyphosate in water samples. Immunoassays would dramatically reduce the costs of water sampling for glyphosate as compared to current analytical methods. The glyphosate molecule is quite small, and has only three chemically distinct sites. Because of these few small sites available for attachment, problems have been encountered by other researchers in developing a immunoassay system for glyphosate. The CHEEC researchers, too, encountered similar difficulties and were unsuccessful in their attempts at developing an immunoassy for glyphosate. Researchers on this project theorized devising a scheme for creating an attachment site internal to the glyphosate molecule, thus presenting the molecule in its native form. Researchers determined this was possible, but this synthesis and process was beyond the scope and resources of this seed grant.

    • Project Period: 1990

      Teratogenic potential of Fusarium moniliforme mycotoxins

      Investigator(s):
      S Hendrich, P Murphy, Department of Food Science and Human Nutrition, Iowa State University
      G Osweiler, Veterinary Diagnostic Laboratory, Iowa State University
      F Ross, T Wilson, National Veterinary Services Laboratory
      Abstract:

      This study looked at the teratogenic potential of Fusarium mycotoxins in animal models. Pregnant rats were exposed to F. moniliforme corn culture material and purified fumonisins B1 (FB1). Researchers then analyzed the uterus for fetal resorption, and the pups for gross anomalies, weight, and corpora lutea were counted. Additionally, corn containing foods were sample assayed for fumonisin content. Results found that under experimental conditions, teratogenic potential exists for FB1, but not for F. moniliforme contaminated corn. This suggests that either F. moniliforme is not as bioavailable as purified FB1 or that crude culture material contains antiteratogens. Human exposure to fumonisins in yellow and white corn meal were measured at 0.75 mg-7.5 mg/55 kg woman per day or about 14-140 ug/kg body weight. This suggests fumonisins might be teratogenic to humans, but do not pose a severe risk. Fumonisins may be very useful in understanding mechanisms of growth-related signal transduction.

      Publications:

      Lebepe-Mazur S, Bal H, Hopmans E, Murphy P, Hendrich S; Fumonisin B is Fetotoxic in Rats. Vet. Human Toxicol. 1995; 37:126-130

    • Project Period: 1990

      Ultraviolet phototoxicity of some non-steroidal anti-inflammatory agents (NSAIDS) on the retina of the eye

      Investigator(s):
      TK Shires, Department of Pharmacology; JS Pulido, Department of Ophthalmology, The University of Iowa
      Abstract:

      Progressive global stratospheric ozone depletion and the resulting elevation in ultraviolet radiation presents the prospect of a significant human health hazard. In the eye, the cornea, lens, and retina have well-established UV radiation pathologies. Increased UV exposures may also intensify the UV-phototoxicity in some therapeutic agents widely used by the general public. This study examined a number of anti-inflammatory analgesics know to be UV-phototoxic in the skin, but with as yet unreported effects in the eye. Study investigators hypothesize that these widely used drugs compound the risk of retinal damage in people who have outdoor occupations.

    • Project Period: 1989

      Collection of historical municipal drinking water data for Iowa municipalities population 750-1,000

      Investigator(s):
      CF Lynch, M Gleaves, M Finn, Department of Preventive Medicine and Environmental Health, The University of Iowa
      Abstract:

      This data collection and management project was developed to upgrade existing historical information for municipal water supplies in the state of Iowa with populations 750-1,000. There are 77 such communities. These data included the name of the source, the year the supply began providing water to a community, the year a source stopped providing to a community, treatment type, etc. An initial pilot study contacted ten municipal water treatment plants to test the adequacy of the questionnaire. A telephone interview followed within a week of initial contact. Results from the pilot questionnaire showed the data collection process to be efficient, and the remaining communities were contacted in a similar manner. Data collected was added to the CHEEC database on municipal water supplies. This data is being utilized by CHEEC researchers looking at source of drinking water and health effects. Methods developed in this project were later utilized to collect historical data for Iowa towns population 250-749. Technical Report Available.

    • Project Period: 1989

      Feasibility study of DNA flow cytometry in renal cell and colorectal carcinoma among Iowa residents

      Investigator(s):
      CF Lynch, Department of Preventive Medicine and Environmental Health; R Robinson, Department of Pathology, The University of Iowa
      Abstract:

      This study researched the feasibility of performing DNA ploidy analysis on formalin-fixed tissue from patients who participated in a statewide, population-based, case-control study, and who had tumorous tissue removed at the University of Iowa Hospitals and Clinics. Eligible cancer sites included the kidney, colon, and rectum. A data collection form was developed and ploidy analysis was run. These analysis were correlated with known pathologic predictors of outcome, as well as with known risk factors for colorectal carcinoma. Results showed no strong associations between ploidy status and survival predictors nor with any dietary and other potential risk factors.

    • Project Period: 1989

      Development of a model rural injury surveillance program

      Investigator(s):
      JA Merchant, K Donham, Institute of Agriculture Medicine and Occupational Health, Department of Preventive Medicine and Environmental Health, The University of Iowa
      Abstract:

      The goals of this project were to review and evaluate available mortality and morbidity data for farm health and safety in order to develop a farm injury surveillance model. A plan was drafted for a population-based surveillance program, data management system, and surveillance network that could be replicated in any agricultural state or region. Results of a pilot study conducted in several rural hospitals were used to develop a proposal to establish an Injury Prevention Research Center at The University of Iowa. This center was established in 1990 through an award from the National Center for Injury Prevention and Control, Centers for Disease Control and Prevention.

    • Project Period: 1989

      Identification and toxicity of decomposition products of nitrogenous pesticides following ozonation

      Investigator(s):
      BC Kross, M Selim, J Hwang, L Odell, Institute of Agricultural Medicine and Occupational Health, Department of Preventive Medicine and Environmental Health, The University of Iowa
      Abstract:

      This project examined the feasibility of point-of-use (POU)/ point-of-entry (POE) ozone treatment systems for in-home use, and their effectiveness at removing the commonly applied pesticides alachlor, atrazine, cyanazine, metolachlor, metribuzin, and propachlor. Tests were conducted in open and closed systems, and efforts were made to simulate probable demand on the system for in-home use. The effectiveness of the ozone system demonstrates oxidation of the pesticides is closely related to the compound oxidized, the pesticide concentration, the ozone concentration, and contact times. Ranking these compounds to their susceptibility to ozone oxidation, metribuzin is the most easily oxidized, followed by alachlor, metolachlor, atrazine, propachlor, and cyanazine. From the tests performed, given a large enough concentration times time (CT) value, oxidation of the pesticides tested to concentrations below health advisory standards can be achieved through ozone POU/POE systems. A follow up study, titled Destruction of nitrogenous pesticides by combined ozone/H2O2 and enzymatic polymerization process was funded by EPA Hazardous Substance Research Center, Region 7.

    • Project Period: 1989

      Development of methods for epidemiologic studies of birth defects and environmental exposures in Iowa

      Investigator(s):
      R Munger and P Isacson, Department of Preventive Medicine and Environmental Health
      J Hanson, Department of Pediatrics; D Schwartz, Department of Internal Medicine, The University of Iowa
      Abstract:

      The project developed a survey and questionnaire for use in population surveys to assess environmental exposures, lifestyle factors, and genetic factors that may increase the risk of birth defects. The study also focused on development of methods of subject contact and tracking. Questionnaire response rates of mothers were compared between those whose children had birth defects or no birth defects. Additionally, validity of the questionnaires was tracked from responses and the mother's medical record. The subject contact procedures and tracking methods developed in this CHEEC funded pilot study proved beneficial for use in the Iowa Birth Defects Registry in etiologic studies of birth defects. The questionnaire developed in this study was utilized in a project titled Epidemiologic Characterization of Genetic and Environmental Risk Factors for Human Clefts, funded by the National Institute of Dental Research.

    • Project Period: 1989

      Modeling dissolved oxygen, nitrate, and pesticide concentrations in the subsurface environment

      Investigator(s):
      JL Schnoor, DR Nair, Department of Civil and Environmental Engineering, The University of Iowa
      Abstract:

      The objectives of this study were to develop a one dimensional (vertical), time variable mathematical model for the transport and reactions of pesticides and nitrates though the unsaturated zone to surficial aquifers. Testing and validation of the model with data from laboratory and field studies on alachlor, atrazine, and nitrates was conducted. The model can provide better understanding of processes effecting pesticides and nitrates in the subsurface environment. Additionally, the model can provide predictions of pesticide and nitrate concentrations under varied application rates, soil types, climatic conditions, electron acceptor conditions, etc. Two field sites were utilized-Amana, Iowa, and Tipton, Georgia. The model performed well and enabled investigators to acquire additional funding through the EPA Hazardous Substances Research Center for Region 7 and 8 for further research.

      Publications:

      Nair DR, Burken JG, Licht LA, Schnoor JL; Mineralization and Uptake of Triazine Pesticide in Soil - Plant Systems. Journal of Environ. Engineering. 1993; 119(5):842-854

    Other

    • Project Period: 2018 to 2019

      Detection of Neonicotinoid Exposure Among Females Farmers in Iowa

      Collaborating Institution(s)
      Center for Health Effects of Environmental Contamination
      University of Iowa Maternal Fetal Tissue Bank
      University of Iowa College of Public Health
      University of Iowa College of Engineering
      Funding Agency
      Heartland Center for Occupational Health and Safety
      Investigator(s):
      Darrin Thompson
      Matthew Poch
      Chunyun Zhang
      Hans-Joachim Lehmler
      R William Field
      David Cwiertny
      Abstract:

      Neonicotinoids are the most widely used class of agricultural insecticides in the world. Between 2001-2014 usage increased by 3,929 times in Iowa alone.  Despite concerns that neonicotinoids may have a toxic effect on mammalian neurodevelopment, few studies have been conducted to characterize human exposure to neonicotinoids or the insecticides’ potential health risks.  Researchers from the College of Public Health, Civil and Environmental Engineering, the State Hygienic Laboratory, and the University of Iowa’s Maternal-Fetal Tissue Bank (MFTB) will randomly test urine samples from 350 women enrolled in the MFTB for the presence of seven parent neonicotinoids and at least 2 common metabolites - desnitro-imidacloprid and imidacloprid urea.  A cross-sectional study will then be conducted to test the association of exposure to neonicotinoids with the occupation of the maternal donor.  The proposed study will be the first to investigate exposure risks amongst farmers.