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Past CHEEC Research:
Nitrates, Nitrites and Nitrosatable Drugs and the Risk for Selected Birth Defects
Congenital defects are the greatest contributor to infant mortality in the U.S., but the causes for the majority of these defects are either unknown or poorly understood. Amine- and amide-containing (nitrosatable) drugs and other compounds react with nitrite in the stomach to form N-nitroso compounds, which have been found to induce a variety of congenital malformations in animal studies. Previous epidemiologic studies have focused on the separate effects of nitrates, nitrites, and nitrosatable drugs on risk of congenital malformations without consideration of their interaction in the formation of N-nitroso compounds. This study is examining the separate and joint effects of prenatal exposures to nitrates, nitrites, and nitrosatable drugs on the risk for neural tube defects, limb malformations, oral clefts, and heart defects. Cases and controls were obtained from the National Birth Defects Prevention Study (NBDPS), a CDC-funded study that covers populations in 10 different states. Subjects' usual intake of dietary nitrates, nitrites, and nitrosamines was calculated from a food frequency survey. The subject survey will also have information on medications taken one month pre-conception and during the first trimester; these will be classified as to their likelihood of nitrosatability based on the literature and chemical structure. Addresses of Iowa and Texas participants are being linked to community water systems and water nitrate sampling results. The separate and joint effects of nitrosatable precursors on risk of selected malformations will be analyzed. The effects of vitamins C and E (inhibitors of nitrosation) on the relations between nitrate/nitrite intake and nitrosatable drugs and risk of congenital malformations will also be examined. Use of over-the-counter medications is fairly common during pregnancy; several over-the-counter preparations contain nitrosatable compounds as active ingredients. This study will help us understand whether pregnant women who take nitrosatable drugs and also consume greater amounts of nitrates and nitrites are at increased risk of having offspring with birth defects. Exposure Assessment Protocol.
Comprehensive Assessment of Rural Health in Iowa: the Carroll County Well Water Study
Intensive private drinking water well sampling in Carroll County, Iowa, will be conducted in 2007 – 2008 as part of the Comprehensive Assessment of Rural Health in Iowa (CARHI) project. This sampling will be a cooperative effort with the ongoing Iowa Statewide Rural Well Water Survey Phase 2 (SWRL2), a three year project (2006-08) conducted by CHEEC in collaboration with the Iowa County Health Departments and County sanitarians, the Iowa Departments of Public Health and Natural Resources, and other agencies. The intensive sampling effort in Carroll County will include 50 wells for the entire suite of SWRL2 compounds (nutrients, bacteria, metals, pesticides and herbicide degradates). Research questions of interest for this set of wells include are there seasonal variation for certain analytes in a confined geographic area (county), and what are the risk factors related to well characteristics/proximate sources of contaminants for poor water quality? An additional 100 wells will sampled and analyzed for total coliform bacteria, E. coli, enterococci, somatic coliphage, and chloride, as part of a special microbial monitoring study conducted by the University Hygienic Laboratory. The research objectives of the microbial monitoring study are to determine the incidence of enterovirus in private drinking water wells, to determine the occurrence of traditional and non-traditional fecal indicators in groundwater (e.g. somatic coliphage, chloride, and enterococci), and to determine whether the source of fecal pollution is human (by utilizing a human specific molecular marker).
Go to the CDC website for further information: http://www.cdc.gov/ncbddd/duchenne/mdstarnet.htm
Download a pdf brochure: mdstarnet.pdf
Comprehensive Assessment of Rural Health in Iowa (CARHI)—NCEH is funding and providing technical oversight to a 2- to 3-year cooperative surveillance activity that is generating baseline health data for selected rural communities in Iowa. With input from a CARHI committee of stakeholders, the Iowa Department of Public Health (IDPH) is linking environmental and health data from a rural community to allow investigation of health effects possibly associated with the environment, such as effects associated with agricultural exposures. The CARHI committee is developing a tool and process for collecting data and a CARHI database. The committee also is recruiting communities and health care practitioners to participate in the CARHI project. Public health officials will use CARHI data to monitor communities’ health, identify existing or emerging health problems that warrant further investigation, enhance or guide environmental sampling, conduct comprehensive health studies, or target important public health programs such as smoking cessation and safe farming practices.
Agricultural Health Study
Naturally Occurring Ammonia in Drinking Water Wells
Portions of the report submitted to the Iowa Department of Natural Resources are available at http://www.cheec.uiowa.edu/research/ammonia_report.doc . (Note: this report is a Microsoft Word Document).
Residential Radon and Lung Cancer Case-Control Study
Mammography Surveillance Pilot Studies
One Time Testing of Iowa Regulated Drinking Water Supplies
Eight hundred and fifty-six public water systems were tested. One hundred and twenty-five tested positive for one or more pesticides. Five hundred and fifty tested positive for one or more synthetic organic compounds. No measurable concentrations of pesticides or volatile organic chemicals were found in 279 systems. A few water systems had pesticides or volatile organic chemical levels that exceeded U.S. Environmental Protection Agency health advisories or maximum contaminant levels, but contaminant levels high enough to cause an acute health risk were not observed in this study.
The pesticides most commonly found were atrazine, cyanazine (Bladex), alachlor (Lasso), metolachlor (Dual), and 2,4-D. The most frequently found volatile organic chemicals belong to a group called trihalomethanes (THMs). THMs are formed during disinfection when chlorine reacts with organic matter in the water. Para- and meta-xylene, measured as a single compound, was the second most abundant VOC observed.
The following are the most significant findings of this one time testing:
For a copy of this report, contact the University Hygienic Laboratory at (319)335-4500.
Evaluation of a web-based approach to data collection in molecular environmental epidemiological investigations of adverse pregnancy outcomes(2012)
Occurrence of viruses and unregulated contaminants in Iowa public water supply groundwater (2012)
Influence of Redox Fluctuations on Arsenic Dynamics in Iowa Aquifer Materials (2011)
Arsenic is an emerging water quality issue in Iowa’s groundwater. According to the Iowa Department of Natural Resources, there are 69 public water supplies that utilize groundwater with arsenic concentrations greater than the recommended limit and in as recent survey of 473 private wells in Iowa, 48% were found to contain arsenic. This study will help address the issue of arsenic in groundwater by conducting laboratory experiments to better understand the geochemical processes controlling the release of arsenic from soils to groundwater. This project will build on previous work that developed analytical methods for measuring arsenic and investigating the reduction of arsenic by common soil minerals. The objectives of this study are to 1) determine the extent of arsenic incorporation and release from iron minerals commonly found in Iowa aquifers, and 2) measure the release of iron and arsenic from Iowa aquifer materials where arsenic has been identified in the groundwater.
Fate of Endocrine Disruptors, Antibiotics and Pharmaceuticals in Wastewater Treatment Plants (2004)
Biosolids are generally defined as the end-product of production and treatment of sludges generated during wastewater treatment. Beneficial uses of biosolids (e.g., land application, landfill covers, etc.) are expected to increase in the coming years. Wastewaters from domestic and industrial sources are known to contain relatively low concentrations of endocrine disruptors, antibiotics and pharmaceuticals. Most of what is known about the fate of these compounds comes from measurements taken before and after treatment of the liquid component of the wastewater. Very little is known about the fate of these compounds during processing of the solids generated during wastewater treatment. Many of these compounds are likely to partition onto particulate matter due to their hydrophobic nature. Thus, it is important to understand the fate of these compounds during the production and use of biosolids. Aqueous samples collected at points throughout a wastewater treatment plant were processed and analyzed for acetaminophen, caffeine, cotinine, ibuprofen, 4-nonylphenol, sulfamethoxazole, triclosan, and trimethoprim. Most aqueous phase removal occurred during primary clarification and/or activated sludge treatment while little or no aqueous phase removal resulted from secondary clarification or chlorination/dechlorination. Sorption isotherms determined for each compound on biosolids from the plant indicated compound specific sorption behavior. Caffeine, cotinine and acetaminophen were significantly removed from the aqueous phase during activated sludge treatment. This implicates biotransformation as a primary removal process given the low sorption potential of these chemicals. Sulfamethoxazole and trimethoprim also have low sorption potential, but are more chemically stabile such that only a small quantity of each was removed during activated sludge treatment. Ibuprofen, 4-nonylphenol and triclosan were significantly removed from the aqueous phase during activated sludge treatment, likely as a result of sorption processes as evidenced by high log Kow values and high concentrations of triclosan and 4-nonylphenol in analyzed biosolids.
Urinary Pesticide Metabolite Levels and Reproductive Effects: A Prospective, Pilot Study of Partners of Pregnant Women in Iowa (2003)
This study hypothesized that the variance in semen quality between geographic locations may be related to recent exposure to environmental toxins, particularly agricultural chemicals. Prospective, multi-center studies have demonstrated geographical variations in semen quality. A recent study of semen quality in four US cities found male partners of pregnant women a rural center (MO) to have significantly lower sperm counts and motility than men recruited from urban centers (NY, MN and CA). A small study of men from this population residing in MO demonstrated an association between semen quality and levels of urinary pesticide metabolites, while men in MN had few detectable levels. The study proposed to examine the relationship between semen quality and urinary pesticide metabolites in partners of pregnant women receiving obstetrical care at University of Iowa Hospitals and Clinics.
Iowa Community Private Well Study (2002)
Conducted from June 2002-January 2003, the study aimed to achieve a better understanding of private drinking water wells in incorporated Iowa towns not served by a public water supply system. Water samples were analyzed by the University of Iowa Hygienic Laboratory (duplicate samples analyzed at USGS laboratories) for common use pesticides, nitrogen compounds, inorganics, bacteria, and VOCs. The study design contained a random and focused component. * Random Study Methodology: Approximately 103 drinking water wells from towns that did not have a public water supply were selected. A weighted distribution of households from US Census data was employed to select wells (i.e.- towns with a higher number of households stood a greater chance of having a well selected). County environmental health specialists visited these towns, located randomly generated points on maps, and found the nearest building to draw a water sample. Fifty distinct towns had one or more wells sampled. * Focus Study Methodology: The focus study employed the use of existing databases of potential contamination sources to intensively sample 15 communities. Selection criteria for these towns considered: towns utilizing private septic systems, existence of underground storage tanks, location of agricultural grain and chemical storage dealerships, regional hydrogeology, active and closed landfills, feedlots, railroad systems, industries in violation of wastewater permit applications (including stormwater permits), nearby uncontrolled sites identified by the Iowa Department of Natural Resources (IDNR), and Resource Conservation and Recovery Act (RCRA)/Superfund sites. www.cheec.uiowa.edu/private_well/index.htm
A fact sheet in PDF is available here: http://www.cheec.uiowa.edu/research/prv_well.pdf
Analysis of Environmental Exposures in Hoop Structures and Conventional Confinement Swine Barns (1999)
A major health concern in swine farming is inhalation of toxicants, which may lead to significant morbidity among swine farmers. Exposures to hydrogen sulfide, ammonia, dust and endotoxin have been linked to a number of health problems in workers, including upper airway diseases, lower airway diseases and interstitial diseases. In addition, outdoor air quality in proximity to swine operations has become a major concern in recent years. Neighbor complaints have been increasing as swine units become larger and more densely located in the neighboring community. While health effects related to odors from livestock units are very difficult to determine, the public perception that odors contain toxic substances has resulted in reports of headaches, nausea and other health complaints in neighbors. In recent years, hoop structures have emerged as an alternative method of housing hogs, and appear to have environmental benefits (related to air and water quality) in comparison to conventional confinement facilities. The purposes of this study are to 1) quantify airborne contaminant concentrations and exposure duration in hoop barns and conventional confinement barns controlling for location, season, micrometeorological conditions, animal density and other factors, and 2) to compare the exposure of airborne contaminants around and downwind of hoop structures and conventional confinement structures. The study will be conducted utilizing a pork producing farm with 3-5 hoop barns and 3-5 confinement buildings on a nearby site. The 15-month project will be a joint effort of researchers from The University of Iowa and Iowa State University; field sampling will be coordinated between study staffs, and laboratory analyses will be conducted utilizing labs at both institutions (ISU Odor Laboratory, ISU Animal Science Department, UI Inhalation Toxicology Facility), which specialize in specific contaminant identification and quantification.
Antibiotics in Surface Water (1999)
In 1999, CHEEC and the Iowa District of the United States Geological Survey (USGS) joined in a collaboratively funded project investigating the presence of antibiotics/antimicrobials in Iowa surface waters. The study objectives are to provide baseline data for types of antimicrobial compounds present, concentrations, and geographical distribution. Thirty sites from across the state were selected representing a cross section of large and small watersheds and stream flows. Of secondary importance of this study was for laboratory methods development for detection of these compounds. Thirty-one sites from across the state were sampled, representing large and small stream flows. Streams were sampled once during the first peak runoff event following snow melt in April 1999. These 15 distinct antibiotics were sampled: carbadox, spectinomycin, sulfamethoxazol, erythromycin, sulfamethazine, trimethoprin, erythromycin - H2O, sulfachloropyrizadine, tylosin, ivermectin, sulfadimethoxine, virginiamycin, lincomycin, sulfamerazine, and tetracyclines (total). Analytical results show that 16 of the 31 stream samples had positive detections for antibiotics. Sulfamethazine was detected in 10 samples, tetracycline (total) in 6, and lincomycin in 1. One stream had two detections of a single compound. All of the concentrations were below .5 micrograms/L (parts per billion). The results of this work were first presented at a 1999 USGS meeting titled Effects of Animal Feeding Operations on Hydrologic Resources and the Environment. Proceedings are available at http://water.usgs.gov/owq/AFO/proceedings/afo/index.html .
Findings from this initial reconnaissance laid the groundwork for the the Kolpin et al journal article in Environmental Science and Technology, titled Pharmaceuticals, Hormones, and Other Organic Wastewater Contaminants in U.S. Streams, 1999-2000: A National Reconnaissance; Environ. Sci. Technol., 36 (6), 1202 -1211, 2002
For a more thorough discussion of emerging contamination of water sources, see the USGS Toxic Substances Hydrology Program .