Why are PFAS a Contaminant of Emerging Concern?
PFAS sources: Recent testing has identified per- and polyfluoroalkyl substances in the environment from various sources, including industrial discharges to air and water, aqueous film-forming foam (AFFF) used on military bases and fire stations, agricultural areas with biosolids applications, and urban areas with municipal wastewater treatment discharges.
PFAS in the human body: Data from the National Health and Nutrition Examination Survey (NHANES) demonstrate that most adolescents and adults have detectable levels of per- and polyfluoroalkyl substances in their blood (CDC, 2018). However, potential PFAS exposure pathways are not assessed as part of NHANES, and the correlation between environmental exposure and serum levels is not well understood.
PFAS in the environment: Sites with elevated levels of per- and polyfluoroalkyl substances in drinking water continue to emerge, and data on PFAS in air, food, and indoor dust are limited. PFAS compounds have been identified in drinking water derived from surface water and groundwater. The EPA has not issued any Maximum Contaminant Levels for PFAS, but in 2012, PFOS and PFOA were added to the third Unregulated Contaminant Monitoring Rule (UCMR 3), prompting testing requirements for all public drinking water systems.
PFAS toxicity: There is limited research on the potential toxicity of PFAS in humans. In 2016, the EPA issued a lifetime health advisory (LHA) for PFOS and PFOA of 70 parts-per-trillion (EPA 2016a; EPA 2016b). The Agency for Toxic Substances and Disease Registry (ATSDR) released an updated draft of the toxicological profile for 14 per- and polyfluoroalkyl compounds in June 2018, proposing much lower minimum risk levels for PFAS and PFOA (ATSDR, 2018b).