Sunderland, Elsie M., Xindi C. Hu, Clifton Dassuncao, Andrea K. Tokranov, Charlotte C. Wagner, and Joseph, G. Allen. A review of the pathways of human exposure to poly- and perfluoroalkyl substances (PFAS) and present understanding of health effects. Journal of Exposure Science & Environmental Epidemiology (2018).
Here, we review present understanding of sources and trends in human exposure to poly- and perfluoroalkyl substances (PFAS) and epidemiologic evidence for impacts on cancer, immune function, metabolic outcomes, and neurodevelopment. More than 4000 PFAS have been manufactured by humans and hundreds have been detected in environmental samples.Direct exposures due to use in products can be quickly phased out by shifts in chemical production but exposures driven by PFAS accumulation in the ocean and marine food chains and contamination of groundwater p ersist over long timescales. Serum concentrations of legacy PFAS in humans are declining globally but total exposures to newer PFAS and precursor compounds have not been well characterized. Human exposures to legacy PFAS from seafood and drinking water are stable or increasing in many regions, suggesting observed declines reflect phase-outs in legacy PFAS use in consumer products. Many regions global ly are continuing to discover PFAS contaminated sites from aqueous film forming foam (AFFF) use, particularly next to airports and military bases. Exposures from food packaging and indoor environments are uncertain due to a rapidly changing chemical landscape where legacy PFAS have been replaced by diverse precursors and custom molecules that are difficult to detect. Multiple studies find significant associations between PFAS exposure and adverse immune outcomes in children. Dyslipidemia is the strongest metabolic outcome associated with PFAS exposure. Evidence for cancer is limited to manufacturing locations with extremely high exposures and insufficient data are available to characterize impacts of PFAS exposures on neurodevelopment. Preliminary evidence suggests significant health effects associated with exposures to emerging PFAS. Lessons learned from legacy PFAS indicate that limited data should not be used as a justification to delay risk mitigation actions for replacement PFAS.
