CHEEC Seed Grants: FY 1996

Flow cytometric assessment of chromosomal damage induced by environmental contaminants 
SL Berberich, GR Hallberg, MD Wichman, University Hygienic Laboratory, The University of Iowa

A prospective cohort study of municipal drinking water nitrate level and cancer risk: The Iowa Women's Health Study 
JR Cerhan, CF Lynch, BC Kross, Department of Preventive Medicine and Environmental Health, The University of Iowa; W Zheng, A Folsom, School of Public Health, University of Minnesota

Spatial variability of 226radium in a water distribution system 
LJ Fuortes, EL Fisher, Department of Preventive Medicine and Environmental Health, The University of Iowa

Pesticides in ambient air and precipitation: implications for exposure assessment 
GR Hallberg, B Coppage, GM Breuer, D Larrabee-Zierath, University Hygienic Laboratory, The University of Iowa

Evaluation of pesticide exposure during application and incidental contact with treated areas of turf 
BC Kross, H Nicholson, L Olgilvie, Department of Preventive Medicine and Environmental Health, The University of Iowa

Municipal water softening and mortality rates of heart disease in Iowa 
GF Parkin, Department of Civil and Environmental Engineering; CF Lynch, Department of Preventive Medicine and Environmental Health, The University of Iowa

An investigation of the potential use of tree-ring chemistry to record the history of site contamination 
JM Pleasants, Department of Zoology and Genetics, Iowa State University; MC Edelson, Ames Laboratory of U.S. Department of Energy

Characterization of lead exposure among bridge repair workers 
SJ Reynolds, LJ Fuortes, Department of Preventive Medicine and Environmental Health, The University of Iowa

The toxicity of 2,4,6-trinitrotoluene (TNT) and its metabolites to populus sp.
JL Schnoor, PL Thompson, Department of Civil and Environmental Engineering, The University of Iowa

 


Flow cytometric assessment of chromosomal damage induced by environmental contaminants 
Investigators: SL Berberich, GR Hallberg, MD Wichman, University Hygienic Laboratory, The University of Iowa 
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.

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

Publication:  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

Spatial variability of 226Radium in a water distribution system
Investigators: LJ Fuortes, EL Fisher, Department of Preventive Medicine and Environmental Health, The University of Iowa 
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:  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

Pesticides in ambient air and precipitation: Implications for exposure assessment 
Investigators: GR Hallberg, B Coppage, GM Breuer, D Larrabee-Zierath, University Hygienic Laboratory, The University of Iowa
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.

Evaluation of pesticide exposure during application and incidental contact with treated areas of turf 
Investigators: BC Kross, H Nicholson, L Ogilvie, Department of Preventive Medicine and Environmental Health, The University of Iowa 
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.

Municipal water softening and mortality rates of heart disease in Iowa 
Investigators: GF Parkin, Department of Civil and Environmental Engineering; CF Lynch, Department of Preventive Medicine and Environmental Health, The University of Iowa 
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.

An investigation of the potential use of tree-ring chemistry to record the history of site contamination 
Investigators: JM Pleasants, Department of Zoology and Genetics, Iowa State University; M Edelson, Ames Laboratory of U.S. Department of Energy 
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.

Characterization of lead exposure among bridge repair workers
Investigators: SJ Reynolds, LJ Fuortes, Department of Preventive Medicine and Environmental Health, The University of Iowa 
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

The toxicity of 2,4,6-trinitrotoluene (TNT) and its metabolites to Populus sp. 
Investigators: JL Schnoor, PL Thompson, Department of Civil and Environmental Engineering, The University of Iowa 
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