Polyfluoroalkyl substance exposure in the Mid-Ohio River Valley, 1991-2012

摘要

Background: Industrial discharges of perfluorooctanoic acid (PFOA) to the Ohio River, contaminating water systems near Parkersburg, WV, were previously associated with nearby residents' serum PFOA concentrations above US population medians. Ohio River PFOA concentrations downstream are elevated, suggesting Mid-Ohio River Valley (ORV) residents are exposed through drinking water. We quantified per- and polyfluoroalkyl substances (PFAS) in Mid-ORV resident sera collected between 1991 and 2013 and determined whether the Ohio River and Ohio River Aquifer were exposure sources. Methods: Using PFAS measurements in 1608 sera from 931 participants, we assessed water source associations using linear mixed-effects models. We estimated between-sample serum PFOA using one-compartment pharmacokinetics for participants with multiple samples. Results: In sera collected as early as 1991, PFOA (median=7.6ng/mL) was detected in 99.9%; 47% had concentrations greater than US population 95th percentiles. Five other PFAS were detected in > 82% of samples, with median concentrations similar to the US population. Serum PFOA was significantly associated with water source, sampling year and age, tap water consumption, pregnancy, gravidity and breastfeeding, and was 40-60% lower with granular activated carbon (GAC) use. Repeated measurements and pharmacokinetics suggest serum PFOA peaked in 2000-2006 for participants using water without GAC treatment; where GAC was used, serum PFOA concentrations decreased from 1991 to 2012. Conclusions: Mid-ORV residents appear to have PFOA, but not other PFAS, serum concentrations above US population levels. Drinking water from the Ohio River and Ohio River Aquifer, primarily contaminated by industrial discharges 209-666 kilometers upstream, is likely the primary exposure source. GAC treatment of drinking water mitigates, but does not eliminate, PFOA exposure. Funding: U01ES012770, U01ES019453, P30ES006096, R21ES017176, T32ES10957, R834788