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.