Polychlorinated biphenyls and incident coronary heart disease-related outcomes in Great Lakes fish consumers.

BACKGROUND: Exposure to polychlorinated biphenyls (PCBs) has been linked to risk factors for cardiovascular disease such as increased inflammation, accelerated atherosclerosis, diabetes, and sex hormone dysregulation. Furthermore, there is increasing evidence suggesting associations between internal dose of PCBs and cardiovascular outcomes. OBJECTIVES: The purpose of this study is to investigate longitudinal associations of PCBs with coronary heart disease (CHD)-related outcomes in a cohort of Great Lakes sport fish consumers. METHODS: The Great Lakes Sport Fish Consumer cohort was established in the early 1990's. Eight hundred nineteen participants were followed from 1993 to 2017. Serum PCBs were measured in 1994/1995 (baseline), in 2001, and in 2004, while health history questionnaires were administered in 1996, 2003, 2010, and 2017. Cox models were used to prospectively investigate associations of total PCBs and PCB groupings, based on aryl hydrocarbon receptor activity, with incident self-reported physician diagnosis of coronary heart disease (CHD), myocardial infarction (MI), and angina pectoris. RESULTS: A 2-fold increase in phenobarbital-type PCBs was associated with a 72% increase in likelihood of self-reported incident diagnosis of CHD (HR=1.72, 95% CI: 1.06-2.81; p=0.0294). Similar results were observed for total PCBs (HR=1.68, 95% CI: 1.05-2.69; p=0.0306) and mixed methacholine/phenobarbital type (mixed-type) PCBs (HR=1.60, 95% CI: 1.02-2.52; p=0.0427), but not methacholine-type PCBs. PCBs were not strongly associated with risk of MI or angina. CONCLUSIONS: This study presents evidence that exposure to PCBs increases the risk of developing coronary heart disease. Given the large number of risk factors and causal pathways for CHD, future research is required to better understand biological mechanisms of action for PCBs on CHD.

An Occupational Legacy: Malignant Mesothelioma Incidence and Mortality in Wisconsin.

OBJECTIVES: The aim of the study was to describe mesothelioma occurrence in Wisconsin from 1997 to 2013 by usual industry and occupation (I&O), including occupations generally considered low risk. METHODS: Population-based rates and standardized incidence and mortality ratios were calculated. Two case-control analyses were designed to compare mesothelioma incidence and mortality in specific I&O groups with occurrence of (1) brain and central nervous system cancers and (2) other causes of death, using logistic regression. RESULTS: Mesothelioma incidence and mortality were elevated in Wisconsin (SIRadj = 1.20 [1.13 to 1.28]; SMRadj = 1.30 [1.22 to 1.38]). Certain industry (construction, manufacturing) and occupation (construction and extraction) groups were associated with increased odds of mesothelioma, with some evidence of increased risk among teachers. CONCLUSIONS: Forty years after the Occupational and Safety Health Act, mesothelioma incidence and mortality remain elevated in Wisconsin, with increased risk continuing for certain I&O groups.

Lead Exposure Among Workers at a Shipyard-Wisconsin, 2015 to 2016.

OBJECTIVE: In March 2016, the state health departments of Wisconsin and Minnesota learned of three shipyard workers with blood lead levels (BLLs) more than 40 µg/dL. An investigation was conducted to determine the extent of and risk factors for the exposure. METHODS: We defined a case as an elevated BLL more than or equal to 5 µg/dL in a shipyard worker. Workers were interviewed regarding their symptoms and personal protective equipment (PPE) use. RESULTS: Of 357 workers, 65.0% had received more than or equal to 1 BLL test. Among tested workers, 171 (73.7%) had BLLmax more than or equal to 5 µg/dL. Workers who received respirator training or fit testing had a median BLLmax of 18.0 µg/dL, similar to the median BLLmax of workers who did not receive such training (22.6 µg/dL, P = 0.20). CONCLUSIONS: Our findings emphasize the importance of adequate provision and use of PPE to prevent occupational lead exposure.

Association of methylmercury intake from seafood consumption and blood mercury level among the Asian and Non-Asian populations in the United States.

BACKGROUND: MeHg is a well-established neurotoxicant for fetal brain growth and development and has been shown to increase the risk of cardiovascular disease in aging populations. In the U.S., Asian populations are of particular concern because of their seafood consumption behaviors. OBJECTIVES: Our objective was to calculate the average daily MeHg intake (ADMI) from seafood and to assess the relationship between ADMI with blood methylmercury (BMeHg) concentrations, specifically among women of reproductive age (WORA) and adults ≥ 50 years of age. METHODS: We estimated ADMI from seafood using the 30-day fish consumption data from the NHANES 2011-2014 datasets. Using multivariable linear regression, we estimated the proportional change in mean BMeHg associated with a doubling of the ADMI. Further, correlations between ADMI and BMeHg were compared between Asians and other racial/ethnic groups. RESULTS: Our analysis found both Asian WORA and Asian adults age ≥ 50 years old had significantly higher BMeHg levels and ADMI than their Non-Asian counterparts. Correlations between ADMI from seafood and blood Hg levels were stronger among Asian WORA than among Non-Asian WORA. Key fish species that influenced the dietary MeHg intake for Asians were mackerel, tuna, and "other known/unknown fish species". CONCLUSION: We confirmed that Asian populations have higher MeHg intake than the Non-Asian population in the U.S. and seafood intake is a key predictor of blood Hg concentration, especially among Asian women of reproductive age. Future studies should incorporate information on other known and unknown fish species that are frequently consumed by Asian populations and different parts and fish organs eaten to better understand determinants of MeHg exposure.

Private-well stewardship among a general population based sample of private well-owners.

Private well stewardship, including on-going testing and treatment, can ensure private well users are able to maintain source-water quality and prevent exposures to potentially harmful constituents in primary drinking water supplies. Unlike municipal water supplies, private well users are largely responsible for their own testing and treatment and well stewardship is often minimal. The importance of factors influencing regular testing, and treatment behaviors, including knowledge, risk perception, convenience and social norms, can vary by geography and population characteristics. The primary goals of this study were to survey a general statewide population of private well users in Wisconsin in order to quantify testing and treatment patterns and gather data on motivations and barriers to well stewardship. The majority of respondents reported using and drinking well water daily but only about one half of respondents reported testing their wells in the last ten years and of these, only 10% reported testing in the last 12months. Bacteria and nitrates were contaminants most often tested; and, a private laboratory most often conducted testing. The most commonly reported water treatment was a water softener. Living in a particular geographic region and income were the most significant predictors of water testing and treatment. Iron and hardness, which influence water aesthetics but not always safety, were the most commonly reported water quality problems. Health concerns or perceived lack thereof were, respectively, motivators and barriers to testing and treatment. Limited knowledge of testing and treatment options were also identified as barriers. Results confirm previous findings that well stewardship practices are minimal and often context specific. Understanding the target population's perceptions of risk and knowledge are important elements to consider in identifying vulnerable populations and developing education and policy efforts to improve well stewardship.

Elevated Blood Lead Levels Associated with Retained Bullet Fragments - United States, 2003-2012.

An estimated 115,000 firearm injuries occur annually in the United States, and approximately 70% are nonfatal (1). Retained bullet fragments (RBFs) are an infrequently reported, but important, cause of lead toxicity; symptoms are often nonspecific and can appear years after suffering a gunshot wound (2,3). Adult blood lead level (BLL) screening is most commonly indicated for monitoring of occupational lead exposure; routine testing of adults with RBFs is infrequent (3). States collaborate with CDC's National Institute for Occupational Safety and Health (NIOSH) to monitor elevated BLLs through the Adult Blood Lead Epidemiology and Surveillance (ABLES) program (4,5). To help assess the public health burden of RBFs, data for persons with BLLs ≥10 µg/dL reported to ABLES during 2003-2012 were analyzed. An RBF-associated case was defined as a BLL ≥10 µg/dL in a person with an RBF. A non-RBF-associated case was defined as a BLL ≥10 µg/dL without an RBF. During 2003-2012, a total of 145,811 persons aged ≥16 years with BLLs ≥10 µg/dL were reported to ABLES in 41 states. Among these, 457 RBF-associated cases were identified with a maximum RBF-associated BLL of 306 µg/dL. RBF-associated cases accounted for 0.3% of all BLLs ≥10 µg/dL and 4.9% of BLLs ≥80 µg/dL. Elevated BLLs associated with RBFs occurred primarily among young adult males in nonoccupational settings. Low levels of suspicion of lead toxicity from RBFs by medical providers might cause a delay in diagnosis (3). Health care providers should inquire about an RBF as the potential cause for lead toxicity in an adult with an elevated BLL whose lead exposure is undetermined.

Perfluoroalkyl substances and fish consumption.

BACKGROUND: Perfluoroalkyl substances (PFAS) are an emerging class of contaminants. Certain PFAS are regulated or voluntarily limited due to concern about environmental persistence and adverse health effects, including thyroid disease and dyslipidemia. The major source of PFAS exposure in the general population is thought to be consumption of seafood. OBJECTIVES: In this analysis we examine PFAS levels and their determinants, as well as associations between PFAS levels and self-reported fish and shellfish consumption, using a representative sample of the U.S. METHODS: Data on PFAS levels and self-reported fish consumption over the past 30 days were collected from the 2007-2008, 2009-2010, 2011-2012, and 2013-2014 cycles of the National Health and Nutrition Examination Survey. Twelve different PFAS were measured in serum samples from participants. Ordinary least squares regression models were used to identify factors (demographic characteristics and fish consumption habits) associated with serum PFAS concentrations. Additional models were further adjusted for other potential exposures including military service and consumption of ready-to-eat and fast foods. RESULTS: Seven PFAS were detected in at least 30% of participants and were examined in subsequent analyses (PFDA, PFOA, PFOS, PFHxS, MPAH, PFNA, PFUA). The PFAS with the highest concentrations were PFOS, followed by PFOA, PFHxS and PFNA (medians of 8.3, 2.7, 1.5 and 1.0ng/mL). Fish consumption was generally low, with a median of 1.2 fish meals and 0.14 shellfish meals, reported over the past 30 days. After adjusting for demographic characteristics, total fish consumption was associated with reduced MPAH, and with elevated PFDE, PFNA and PFuDA. Shellfish consumption was associated with elevations of all PFAS examined except MPAH. Certain specific fish and shellfish types were also associated with specific PFAS. Adjustment for additional exposure variables resulted in little to no change in effect estimates for seafood variables. CONCLUSIONS: PFAS are emerging contaminants with widespread exposure, persistence, and potential for adverse health effects. In the general population, fish and shellfish consumption are associated with PFAS levels, which may indicate an avenue for education and outreach.

Heat Vulnerability Index Mapping for Milwaukee and Wisconsin.

CONTEXT: Extreme heat waves elevate the population's risk for heat-related morbidity and mortality, specifically for vulnerable groups such as older adults and young children. In this context, we developed 2 Heat Vulnerability Indices (HVIs), one for the state of Wisconsin and one for the Milwaukee metropolitan area. OBJECTIVE: Through the creation of an HVI, state and local agencies will be able to use the indices as a planning tool for extreme heat events. DESIGN: Data used for the HVIs were grouped into 4 categories: (1) population density; (2) health factors; (3) demographic and socioeconomic factors; and (4) natural and built environment factors. These categories were mapped at the Census block group level. MAIN OUTCOME MEASURES: Unweighted z-score data were used to determine index scores, which were then mapped by quantiles ranging from "high" to "low" vulnerability. RESULTS: Statewide, Menominee County exhibited the highest vulnerability to extreme heat. Milwaukee HVI findings indicated high vulnerability in the city's inner core versus low vulnerability along the lakeshore. CONCLUSION: Visualization of vulnerability could help local public health agencies prepare for future extreme heat events.

High-Precision (MC-ICPMS) Isotope Ratio Analysis Reveals Contrasting Sources of Elevated Blood Lead Levels of an Adult with Retained Bullet Fragments, and of His Child, in Milwaukee, Wisconsin.

Exposure to the neurotoxic element lead (Pb) continues to be a major human health concern, particularly for children in US urban settings, and the need for robust tools for assessment of exposure sources has never been greater. The latest generation of multicollector inductively coupled plasma mass spectrometry (MC-ICPMS) instrumentation offers the capability of using Pb isotopic signatures as a tool for environmental source tracking in public health. We present a case where MC-ICPMS was applied to isotopically resolve Pb sources in human clinical samples. An adult male and his child residing in Milwaukee, Wisconsin, presented to care in August 2015 with elevated blood lead levels (BLLs) (>200 µg/dL for the adult and 10 µg/dL for the child). The adult subject is a gunshot victim who had multiple bullet fragments embedded in soft tissue of his thigh for approximately 10 years. This study compared the high-precision isotopic fingerprints (<1 ‰ 2σ external precision) of Pb in the adult's and child's whole blood (WB) to the following possible Pb sources: a surgically extracted bullet fragment, household paint samples and tap water, and a Pb water-distribution pipe removed from servicing a house in the same neighborhood. Pb in the bullet and adult WB were nearly isotopically indistinguishable (matching within 0.05-0.56 ‰), indicating that bullet fragments embedded in soft tissue could be the cause of both acute and chronic elevated blood Pb levels. Among other sources investigated, no single source dominated the child's exposure profile as reflected in the elevated BLL.

Associations Between Fish Consumption and Contaminant Biomarkers With Cardiovascular Conditions Among Older Male Anglers in Wisconsin.

OBJECTIVE: The aim of this study was to determine fish consumption habits and contaminant exposures associated with adverse cardiovascular outcomes among older male anglers. METHODS: One hundred fifty-four men aged 50 years and older living and fishing in Wisconsin completed a detailed survey and provided hair and blood samples. Associations between fish consumption and body burdens of several contaminants, with self-reported cardiovascular outcomes, were evaluated. RESULTS: Consuming fish species with higher methyl mercury content was positively associated with odds of angina, coronary heart disease (CHD), or heart attack, while consuming fattier species was negatively associated with high blood pressure or high cholesterol. Total mercury in blood was associated with 27% higher odds of heart attack, and certain classes of polychlorinated biphenyls were positively associated with CHD. CONCLUSION: Total mercury exposures may affect cardiovascular outcomes. Educational interventions promoting consumption of fish low in methyl mercury among older male anglers are needed.

Fish Consumption, Levels of Nutrients and Contaminants, and Endocrine-Related Health Outcomes Among Older Male Anglers in Wisconsin.

OBJECTIVE: The aim of this study was to examine associations between endocrine disorders, fish consumption habits, and biomarkers of contaminants and nutrients METHODS: : Male anglers aged at least 50 years living in Wisconsin (n = 154) completed a questionnaire and provided biological samples. Adjusted logistic regression models were used to evaluate risk factors for endocrine outcomes. RESULTS: Nineteen percent of anglers reported either pre-diabetes or diabetes, while 4.6% reported thyroid disease. There were few associations between endocrine disease and fish consumption, fish meal source, or species, aside from a notable increase in diabetes risk with lake trout consumption. Docosahexaenoic acid, certain polychlorinated biphenyls (PCBs), and perfluorinated compounds were associated with an increased risk of diabetes or pre-diabetes. PCBs were associated with a decreased risk of thyroid disease. CONCLUSION: Fish consumption patterns may affect risk for endocrine outcomes, but direction and magnitude of association may depend on the balance of the contaminants and nutrients in the individual diet.

Perfluoroalkyl substances in older male anglers in Wisconsin.

BACKGROUND: Perfluoroalkyl substances (PFAS) are an emerging class of contaminants. Certain PFAS are regulated or voluntarily limited due to concern about environmental persistence and adverse health effects, including thyroid disease and to dyslipidemia. The major source of PFAS exposure in the general population is seafood. OBJECTIVES: In this analysis we examine PFAS levels and their determinants, as well as associations between PFAS levels and self-reported health outcomes, in a group of older male anglers in Wisconsin with high fish consumption. METHODS: A biomonitoring study of male anglers aged 50 and older living in Wisconsin collected detailed information on fish consumption, demographics and self-reported health outcomes, along with hair and blood samples for biomarker analysis. Sixteen different PFAS were extracted from serum samples. Regression models were used to identify factors (demographic characteristics and fish consumption habits) associated with PFAS biomarker levels in blood, as well as associations between PFAS and self-reported health outcomes, adjusting for potential confounders. RESULTS: Seven PFAS were detected in at least 30% of participants and were used in subsequent analyses (PFDA, PFHpS, PFHxS, PFNA, PFOA, PFOS, PFuDA). The PFAS with the highest levels were PFOS, followed by PFOA, PFHxS and PFNA (medians of 19.0, 2.5, 1.8 and 1.4ng/mL). In general, increasing age was associated with higher PFAS levels, while increasing BMI were associated with lower PFAS levels. Greater alcohol consumption was associated with higher levels of PFHpS, PFHxS and PFOA. Associations with smoking and employment did not show a consistent pattern. Associations between fish consumption and PFAS were generally weak, with the exception of notably higher PFDA and PFHpS with both other locally-caught fish, and restaurant-purchased fish. Regarding associations with health outcomes, PFuDA, PFNA and PFDA were all associated with increased risk of pre-diabetes and/or diabetes. PFHpS was associated with a significantly increased risk of high cholesterol; PFDA and PFuDA also showed notable, though non-significant associations. All PFAS evaluated were associated with lower risk of hypertension although the only significant odds ratio was that for PFNA. There were no associations between any of the PFAS examined and either coronary heart disease, or the grouped outcome of any cardiovascular condition. CONCLUSIONS: PFAS are emerging contaminants with widespread exposure, persistence, and potential for adverse health effects. In this study population, demographic patterns may reflect differences in exposure sources, or possibly differences in adsorption and metabolism. PFAS were associated mainly with endocrine related outcomes, with a general trend towards increased risk of glucose intolerance and high cholesterol. Continued research on the risks and benefits of fish consumption is important due to potential exposure to PFAS and noted associations with highly prevalent adverse health outcomes.

Levels of persistent contaminants in relation to fish consumption among older male anglers in Wisconsin.

Fish are an important source of nutrients which may reduce risk of adverse health outcomes such as cardiovascular disease; however, fish may also contain significant amounts of environmental pollutants such as mercury, polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and perfluorinated compounds (PFCs, also called perfluoroalkyl compounds), which confer increased risk for adverse health effects. The Wisconsin Departments of Health Services and Natural Resources developed a survey instrument, along with a strategy to collect human biological samples to assess the risks and benefits associated with long-term fish consumption among older male anglers in Wisconsin. The target population was men aged 50 years and older, who fish Wisconsin waters and live in the state of Wisconsin. Participants provided blood and hair samples and completed a detailed (paper) questionnaire, which included questions on basic demographics, health status, location of catch and species of fish caught/eaten, consumption of locally caught and commercially purchased fish, and awareness and source of information for local and statewide consumption guidelines. Biological samples were used to assess levels of PCBs, PBDEs, PFCs (blood), and mercury (hair and blood). Quantile regression analysis was used to investigate the associations between biomarker levels and self-reported consumption of fish from the Great Lakes and other areas of concern, other locally caught fish, and commercially purchased fish (meals per year). Respondents had a median age of 60.5 (interquartile range: 56, 67) years. The median fish consumption was 54.5 meals per year, with most fish meals coming from locally-caught fish. Participants had somewhat higher mercury levels compared with the US general population, while levels of other contaminants were similar or lower. Multivariate regression models showed that consumption of fish from the Great Lakes and areas of concern was associated with higher levels of each of the contaminants with the exception of PBDEs, as was consumption of locally caught fish from other water bodies. All commercial fish consumption was also associated with both hair and blood mercury. When looking at specific PCB, PBDE and PFC analytes, consumption of fish from the Great Lakes and areas of concern was associated with higher levels of each of the individual PCB congeners examined, as well as higher levels of all of the PFCs examined, with the exception of PFHxS. Among the PFCs, locally caught fish from other water bodies was also associated with higher levels of each of the congeners examined except PFHxS. Finally, all commercial fish was associated with higher levels of PFHxS.

Electronic Cigarette Exposure: Calls to Wisconsin Poison Control Centers, 2010­2015.

BACKGROUND: E-cigarettes are battery-powered devices that deliver nicotine and flavorings by aerosol and have been marketed in the United States since 2007. Because e-cigarettes have increased in popularity, toxicity potential from device misuse and malfunction also has increased. National data indicate that during 2010­2014, exposure calls to US poison control centers increased only 0.3% for conventional cigarette exposures, whereas calls increased 41.7% for e-cigarette exposures. METHODS: We characterized cigarette and e-cigarette exposure calls to the Wisconsin Poison Center January 1, 2010 through October 10, 2015. We compared cigarette and e-cigarette exposure calls by exposure year, demographic characteristics, caller site, exposure site, exposure route, exposure reason, medical outcome, management site, and level of care at a health care facility. RESULTS: During January 2010 to October 2015, a total of 98 e-cigarette exposure calls were reported, and annual exposure calls increased approximately 17-fold, from 2 to 35. During the same period, 671 single-exposure cigarette calls with stable annual call volumes were reported. E-cigarette exposure calls were associated with children aged ≤5 years (57/98, 58.2%) and adults aged ≥20 years (30/98, 30.6%). Cigarette exposure calls predominated among children aged ≤5 years (643/671, 95.8%). CONCLUSION: The frequency of e-cigarette exposure calls to the Wisconsin Poison Center has increased and is highest among children aged ≤5 years and adults. Strategies are warranted to prevent future poisonings from these devices, including nicotine warning labels and public advisories to keep e-cigarettes away from children.

Comprehension of Fish Consumption Guidelines Among Older Male Anglers in Wisconsin.

Although awareness of Wisconsin's fish consumption guidelines is high among older male anglers, little is known about comprehension of guideline content, and many anglers have levels of contaminants high enough to be associated with adverse health outcomes. The Environmental Protection Agency Great Lakes Restoration Initiative supported evaluation and revision of Wisconsin's fish consumption guideline program, using a web based survey of male Wisconsin anglers over the age of 50. A total of 3740 men completed the online survey; the median age of respondents was 62 years, and nearly all had lived and fished in Wisconsin for over 10 years. Comprehension of guideline content was relatively high, although two knowledge gaps were identified, one relating to mercury exposures and fish preparation, and the other to polychlorinated biphenyl content of certain fish species. The fishing regulations booklet distributed with annual fishing licenses and warning signs posted at fishing locations were commonly reported sources of guideline information in Wisconsin. Residents of coastal counties and consumers of Great Lakes fish were more likely to report guideline knowledge and behavior changes reflective of guideline knowledge, when compared to inland residents and those not consuming Great Lakes fish, respectively. In general, Wisconsin's consumption guidelines do not appear to discourage men from eating the fish they catch; rather, the most common behavioral changes included modifying the species eaten or the water body source of their meals. Continued efforts to educate anglers about the risks and benefits of fish consumption are needed.

Levels of nutrients in relation to fish consumption among older male anglers in Wisconsin.

Fish is an important source of nutrients including omega-3 fatty acids, which may reduce risk of adverse health outcomes such as cardiovascular disease; however, fish may also contain significant amounts of environmental pollutants. The Wisconsin Departments of Health Services and Natural Resources developed a survey instrument, along with a strategy to collect human biological samples to assess the risks and benefits associated with long-term fish consumption among older male anglers in Wisconsin. The target population was men aged 50 years and older, who fish Wisconsin waters and live in the state of Wisconsin. Participants provided blood and hair samples and completed a detailed (paper) questionnaire, which included questions on basic demographics, health status, location of catch and species of fish caught/eaten, consumption of locally caught and commercially purchased fish, and awareness and source of information for local and statewide consumption guidelines. Biological samples were used to assess levels of docosahexaenoic acid (DHA), docosapentaenoic acid (DPA), eicosapentaenoic acid (EPA); vitamin D; and selenium in blood. Quantile regression analysis was used to investigate the associations between biomarker levels and self-reported consumption of fish from the Great Lakes and other areas of concern, other locally caught fish, and commercially purchased fish (meals per year). Respondents were largely non-Hispanic white men in their 60's with at least some college education, and about half were retired. Fish consumption was high (median of 54.5 meals per year), with most fish meals coming from locally-caught fish. Multivariate regression models showed that the effect of supplement use was much greater than that of fish consumption, on nutrient levels, although consumption of fish from the Great Lakes and areas of concern was significantly associated with higher levels of vitamin D even after controlling for supplement usage.

Persistent organic pollutants and biomarkers of diabetes risk in a cohort of Great Lakes sport caught fish consumers.

BACKGROUND: Exposure to persistent organic pollutants (POPs) is associated with increased diabetes risk, although the mechanism of action is not well delineated. METHODS: We investigated established diabetes biomarkers that could implicate potential mechanistic pathways, including C-reactive protein (CRP), a marker of systemic inflammation; gamma glutamyl transferase (GGT), a liver enzyme associated with oxidative stress; and adiponectin, an adipokine modulating glucose regulation and fatty acid oxidation. These biomarkers as well as hemoglobin A1c (HA1c), and POPs [polychlorinated biphenyls (PCBs), p,p-dichlorodiphenyldichloroethylene (DDE) and polybrominated diphenyl ethers (PBDEs)] were measured in a cohort of Great Lakes sport caught fish (GLSCF) consumers. We examined associations of POPs and fish consumption with HA1c and incident diabetes, and evaluated mediation and moderation by the diabetes biomarkers. RESULTS: Odds of incident diabetes were elevated with exposure to DDE and PCBs. DDE and PCB 118 were positively, and fish meals were inversely, associated with HA1c. CRP was inversely associated with saltwater and total fish meals, particularly in persons with higher adiposity, but did not mediate the associations of fish meals with HA1c. There were few associations of POPs with adiponectin, CRP and GGT, with the exception of positive associations of PCB 118 with GGT, PBDEs with GGT in older persons, and PBDEs with adiponectin. Adiponectin, CRP and GGT did not mediate associations of DDE and PCBs with HA1c or incident diabetes. However, the association of DDE with HA1c was stronger in persons with higher CRP, GGT and BMI, and lower adiponectin, while the association of PCB 118 with HA1c was stronger in persons with higher GGT. CONCLUSIONS: These findings suggest that adiponectin, CRP and GGT did not mediate effects of POPs on diabetes or HA1c. However, POPs may have stronger effects on blood glucose in persons at higher risk for diabetes.

Quantile regression in environmental health: Early life lead exposure and end-of-grade exams.

Conditional means regression, including ordinary least squares (OLS), provides an incomplete picture of exposure-response relationships particularly if the primary interest resides in the tail ends of the distribution of the outcome. Quantile regression (QR) offers an alternative methodological approach in which the influence of independent covariates on the outcome can be specified at any location along the distribution of the outcome. We implemented QR to examine heterogeneity in the influence of early childhood lead exposure on reading and math standardized fourth grade tests. In children from two urban school districts (n=1,076), lead exposure was associated with an 18.00 point decrease (95% CI: -48.72, -3.32) at the 10th quantile of reading scores, and a 7.50 point decrease (95% CI: -15.58, 2.07) at the 90th quantile. Wald tests indicated significant heterogeneity of the coefficients across the distribution of quantiles. Math scores did not show heterogeneity of coefficients, but there was a significant difference in the lead effect at the 10th (ß=-17.00, 95% CI: -32.13, -3.27) versus 90th (ß=-4.50, 95% CI: -10.55, 4.50) quantiles. Our results indicate that lead exposure has a greater effect for children in the lower tail of exam scores, a result that is masked by conditional means approaches.