Funded Research

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The following is a listing of Fiscal Year Seed Grant Funding.

2018

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

    2018

    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.

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

    2018

    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.

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

    2018

    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.

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

    2018

    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.

2017

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

    2017

    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.

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

    2017

    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.

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

    2017

    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.

  • Prairie strips for retaining antimicrobial resistant organisms

    2017

    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. 

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

    2017

    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.

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

    2017

    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.

  • 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

    2017

    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

2016

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

    2016

    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. 

  • Environmentally active surface films

    2016

    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.

  • Fate of neonicotinoid insecticides in water and wastewater treatment systems

    2016

    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.

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

    2016

    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.

2015

  • Metagenomic analysis and modeling of environmental resistance to agricultural antibiotics

    2015

    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.

  • A low-cost aerosol sensing estimator for assessing aerosol exposure

    2015

    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).

  • Metabolomics characterization of early biomarkers of microcystin exposure in blood

    2015

    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.

2014

  • Estimating prenatal exposure to lead in Iowa newborns

    2014

    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.

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

    2014

    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.

  • Simple and fast detection of pathogens in recreational waters

    2014

    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.

    Publication:  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

     

2013

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

    2013

    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.

    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.

  • Effects of PCBs on adipocytes and the development of metabolic syndrome

    2013

    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.                                                                                                                                                            

    Publications:

    Gadupudi G, Gourronc FA, Ludewig G, Robertson LW, Klingelhutz AJ. PCB126 inhibits adipogenesis of human preadipocytes. Toxicol In Vitro  2015 29(1):132-141.

  • Enhanced CNS exposure to glyphosate following inhalation resulting from olfactory uptake

    2013

    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

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

    2013

    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.

2012

  • An investigation of carbon nanotube exposure assessment methods

    2012

    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.

  • Functionalized magnetic mesoporous silica for adsorption of arsenic from water

    2012

    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.

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

    2012

    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.

2011

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

    2011

    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.

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

    2011

    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.

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

    2011

    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.

  • Pesticide Exposure and Risk of Endometriosis

    2011

    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. 

2010

  • Siloxanes in Chicago Air

    2010

    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.

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

    2010

    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

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

    2010

    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.

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

    2010

    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

2009

  • Predicting Indoor and Outdoor Air Quality by Indirect Methods

    2009

    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.

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

    2009

    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.

  • Monitoring Contaminant Impact on Biofilm Adaptation with Raman Spectroscopy

    2009

    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.

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

    2009

    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.

  • Effect of Nanoparticle Physicochemical Properties on Lung Surfactant Function

    2009

    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

2008

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

    2008

    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

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

    2008

    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.

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

    2008

    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.

  • Transformation and Fate of Manufactured Metal Nanoparticles in Aqueous Environments

    2008

    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.

  • Effect of Agricultural Pesticides on Prostate Cancer Progression

    2008

    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

2007

  • Mechanisms of Perfluorooctanesulfonamide- Induced Oxidative Stress in Female Rats

    2007

    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.

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

    2007

    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.

  • Arsenic speciation in Iowa's groundwater and surface water

    2007

    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.

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

    2007

    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.

  • Paraquat-Mediated Generation of Endogenous Neurotoxins Resulting from Dopamine Oxidation

    2007

    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.

2006

  • The Prevalence and Control of Fragrance Compounds in Iowa Drinking Water

    2006

    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.

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

    2006

    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.

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

    2006

    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.

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

    2006

    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.

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

    2006

    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.

2005

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

    2005

    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.

  • Passive Sampling of Ambient Air Particulate Matter

    2005

    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

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

    2005

    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.

  • Adsorption of Environmental Pollutants Using Nanocrystalline Zeolites

    2005

    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.

2004

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

    2004

    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

  • Plant-Assisted Bacterial Degradation of Perchlorate

    2004

    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

  • Development of a Passive Air Sampler for Measuring PCBs in Air

    2004

    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.

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

    2004

    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

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

    2004

    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.

2003

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

    2003

    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

  • Heartland Environmental Metal Dental Study

    2003

    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.

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

    2003

    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

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

    2003

    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.

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

    2003

    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.

2002

  • Uptake and Metabolism of Acetanilide Herbicides by Hybrid Poplar Trees

    2002

    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

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

    2002

    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.

  • Pollutants of Emerging Concern in Iowa Air

    2002

    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

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

    2002

    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

  • Cephalosporin Resistant E. coli in Iowa Waterways

    2002

    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.

2001

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

    2001

    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

  • Emission Estimation, Measurement, and Modeling of Ambient Ammonia Concentrations

    2001

    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.

2000

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

    2000

    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

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

    2000

    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.

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

    2000

    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

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

    2000

    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.

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

    2000

    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.

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

    2000

    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

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

    2000

    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.

1999

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

    1999

    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

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

    1999

    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.

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

    1999

    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

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

    1999

    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

1998

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

    1998

    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

  • Prevalence and environmental risk factors for pediatric asthma

    1998

    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.

  • Evaluation of solanesol as a tracer for environmental tobacco smoke

    1998

    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.

  • Effects of bacterial DNA on expression of hypersensitivity pneumonitis

    1998

    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.

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

    1998

    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

1997

  • Respiratory health effects of soybean fungal bioaerosols

    1997

    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

  • Measuring low level arsenic exposure through drinking water

    1997

    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

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

    1997

    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)

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

    1997

    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.

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

    1997

    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

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

    1997

    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

  • Bioaugmentation of the poplar rhizosphere with genetically engineered microorganisms

    1997

    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

1996

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

    1996

    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

  • Characterization of lead exposure among bridge repair workers

    1996

    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

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

    1996

    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.

  • Municipal water softening and mortality rates of heart disease in Iowa

    1996

    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.

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

    1996

    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.

  • Pesticides in ambient air and precipitation: Implications for exposure assessment

    1996

    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.

  • Spatial variability of 226 Radium in a water distribution system

    1996

    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

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

    1996

    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

  • Flow cytometric assessment of chromosomal damage induced by environmental contaminants

    1996

    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.

1995

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

    1995

    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.

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

    1995

    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

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

    1995

    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.

  • Expression of toluene dioxygenase under various redox and substrate conditions

    1995

    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.

1994

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

    1994

    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

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

    1994

    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

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

    1994

    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

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

    1994

    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.

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

    1994

    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

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

    1994

    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.

1993

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

    1993

    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

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

    1993

    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.

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

    1993

    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.

  • Source of drinking water and cancer incidence in Iowa

    1993

    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.

  • Chloramine decomposition product studies

    1993

    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

1992

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

    1992

    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.

  • Comparison of sampling methods for lead in dust

    1992

    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

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

    1992

    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.

  • Validation of family history obtained through parental interview

    1992

    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

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

    1992

    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

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

    1992

    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.

1991

  • Development of a database of environmental exposures among infertile couples

    1991

    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

  • Radon and radium release into drinking water from distribution system deposits

    1991

    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

  • Investigation of pesticides and synthetic organic compounds with adverse reproductive outcomes

    1991

    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

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

    1991

    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.

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

    1991

    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.

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

    1991

    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

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

    1991

    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

1990

  • Analysis of aflatoxins in grain dust

    1990

    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

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

    1990

    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.

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

    1990

    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

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

    1990

    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

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

    1990

    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.

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

    1990

    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

  • Development of an immunoassay for the detection of glyphosate in water

    1990

    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.

  • Teratogenic potential of Fusarium moniliforme mycotoxins

    1990

    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

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

    1990

    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.

1989

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

    1989

    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.

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

    1989

    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.

  • Development of a model rural injury surveillance program

    1989

    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.

  • Identification and toxicity of decomposition products of nitrogenous pesticides following ozonation

    1989

    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.

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

    1989

    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.

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

    1989

    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