Chronic toxicity and uptake of 10 Per- and Polyfluoroalkyl Acids to marine species <i>Americamysis bahia</i> and <i>Atherinops affinis</i>

A lack of marine specific data results in challenges to assessing site-specific ecological risks and developing marine water quality criteria for per- and polyfluoroalkyl substances (PFAS). Here, the toxicity and bioaccumulation of perfluorobutanoic acid (PFBA), perfluorohexanoic acid (PFHxA), perfluorooctanoic acid (PFOA), perfluorodecanoic acid (PFDA), perfluorobutanesulfonic acid (PFBS), perfluorohexanesulfonic acid (PFHxS), perfluorooctanesulfonic acid (PFOS), perfluorodecanesulfonic acid (PFDS), 6:2 fluorotelomer sulfonate (6:2 FTS), and 8:2 fluorotelomer sulfonate (8:2 FTS) were evaluated in marine species using two standard U. S. Environmental Protection Agency (USEPA) 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 day; concentrations typically >1 mg/L) and at 28 day (A. affinis only; concentrations approximately 0.1 mg/L). Americamysis bahia was more sensitive to PFAS than A. affinis. Half-maximal effective concentration (EC50)values derived for 6 PFAS and 3 PFAS for A. bahia and A. affinis, respectively, were greater than 1 mg/L. Half-maximal effective concentration values for A. bahia were negatively correlated with perfluoroalkyl carbon chain length. Toxicological metrics (No effect concentrations [NOEC], Lowest observed effect concentrations [LOEC], 10% effective concentrations [EC10], 20% effective concentrations [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 to 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 (BCFs) for the 10 PFAS ranged over 5 orders of magnitude and were positively correlated with perfluoroalkyl chain length.