Apical effects of simulated maternal exposure of salmonid fishes to novel and typical per- and polyfluoroalkyl substances

Per and polyfluoroalkyl substances (PFAS) are ubiquitous in the environment and have been detected in tissues of wildlife and humans. While new chemicals are continually being added to the PFAS category, information on mechanisms and thresholds for adverse effects of these novel contaminants are often limited. To explore potential adverse effects on fishes caused by maternal exposure, five PFAS, perfluorobutanoic acid (PFBA), perfluorobutanesulfonic acid (PFBS), GenX, perfluorooctanoic acid, and perfluorooctanesulfonic acid (PFOS), were deposited in oocytes of two salmonid species, Arctic char (Salvelinus alpinus) and rainbow trout (Oncorhynchus mykiss), before fertilization. Concentrations in unfertilized oocytes were quantified, and related to apical adverse effects observed during the period from fertilization to swim-up. Significant disruption in hatching and survival of these two species was observed at exposure to 8.7 μg PFOS/g wet weight of char oocyte or 13.5 μg PFOS/g, wet weight trout oocyte. Few apical effects were observed for the novel PFAS alternatives, PFBA, PFBS, or GenX, in char (up to 1.3 μg PFBA/g, 2.6 μg PFBS/g, 1.1 μg GenX/g, wet wt oocyte) or trout (up to 4.9 μg PFBA/g, 8.3 μg PFBS/g, 5.9 μg GenX/g, wet wt oocyte), likely due to faster elimination of these compounds.