ABSTRACT
Many manufactured per- and polyfluorinated alkyl substances (PFAS), like perfluorooctanoic acid (PFOA), are widely used in a number of consumer goods and have emerged as environmentally persistent pollutants. This section summarizes the toxicological effects of PFOA on wildlife and evaluates PFOA toxicity data to derive toxicity reference values (TRVs). Selected ingestion TRVs for mammals were determined by the Benchmark Dose (BMD) approach for sensitive immunotoxicological end points, which gave a lower-bounded 95 percent confidence limit of 1.75 mg/kg-d on a BMD (at one SD) level of 3.06 mg/kg/d. Chronic studies were unavailable for inhalational exposures in mammals; however, sub-chronic bioassays gave a TRV-low of 0.1 mg/m3 and a TRV-high of 1 mg/m3. Insufficient data have precluded the development of TRV values for birds, amphibians, and reptiles, a point which clearly identifies important research needs for PFOA and its derivatives, with respect to such poorly studied animal classes. Similarly, greater insights into the immunotoxicity of PFOA and its immunosuppressive effects require additional research to determine mechanisms of action and identify the species most at risk.
