Chronic toxicity and uptake of 10 per- and polyfluoroalkyl acids to marine species Americamysis bahia and Atherinops affinis

Abstract A lack of marine specific data results in challenges to assessing site-specific ecological risks and developing marine water quality criteria for per- and poly-fluoroalkyl substances (PFAS). Here, the toxicity and bioaccumulation of perfluorobutanoic acid, perfluorohexanoic acid, perfluorooctanoic acid, perfluorodecanoic acid, perfluorobutanesulfonic acid, perfluorohexanesulfonic acid, perfluorooctanesulfonic acid, perfluorodecanesulfonic acid, 6:2 fluorotelomer sulfonate, and 8:2 fluorotelomer sulfonate were evaluated in marine species using two standard U.S. Environmental Protection Agency toxicity species: (1) Mysid shrimp (Americamysis bahia) and (2) topsmelt fish (Atherinops affinis). Concentrations of PFAS in live organisms were measured at the end of the toxicity tests (7 days; concentrations typically > 1 mg/L) and at 28 days (A. affinis only; concentrations ∼0.1 mg/L). Americamysis bahia was more sensitive to PFAS than A. affinis. Half-maximal effective concentration (EC50) values derived for six PFAS and three PFAS for A. bahia and A. affinis, respectively, were > 1 mg/L. Half-maximal effective concentration values (EC50) for A. bahia were negatively correlated with perfluoroalkyl carbon chain length. Toxicological metrics (no effect concentration [NOEC], lowest observed effect concentration, EC10, and EC20) were generated using measured concentrations in water and tissue. In exposures with significant lethality, narcotic mode of action is suggested based on the range of tissue concentration NOECs for PFAS were in the 0.01–100 mg/L range, orders of magnitude higher than environmentally relevant concentrations. As such, adverse effects on these species and endpoints are not likely in marine environment. Bioconcentration factors for the 10 PFAS ranged over five orders of magnitude and were positively correlated with perfluoroalkyl chain length.