Per- and polyfluoroalkyl substances (PFAS) are a group of ubiquitous, highly stable chemicals used in many consumer and industrial products that can have negative health effects in humans including cancer and liver disease. According to the European Food Safety Authority (EFSA), an estimated 86% of dietary PFAS exposure to European adults comes from consumption of contaminated seafood. Fish bioaccumulate PFAS at higher concentrations than the environment with diet suspected to be a contributor of PFAS bioaccumulation. However, to our knowledge there are no studies examining aquaculture feeds as a potential source of PFAS exposure for finfish raised for consumption. This study: (1) developed a liquid chromatography tandem mass spectrometry method for the measurement of 30 PFAS in commercial aquaculture feeds (2) conducted a feeding trial using low and high PFAS feeds at different ration levels to assess accumulation of 30 PFAS in the filets and livers of juvenile red drum (Sciaenops ocellatus), and (3) estimated human PFAS dietary exposure from aquaculture fish filets.
Sixteen PFAS were detected across the 13 feeds, with perfluorooctanesulfonate (PFOS) being the highest concentration detected. In both the filets and the livers, only PFOS was detected above the reporting limits with a maximum of respectively 0.164 ng/g and 0.904 ng/g. Fish given the higher PFOS diet exhibited a higher percentage of detection in their fillets compared to fish given the lower PFOS diet. However, there was a significant difference in size between the feed groups, suggesting a possible growth dilution effect. PFOS did not differ among rations. Using the filet concentrations, estimates of dietary exposure to PFAS did not exceed the tolerable weekly intake limit set by the EFSA.
This study provides an assessment of commercially available feeds for PFAS and the accumulation of these contaminants by fish raised in via aquaculture. While fish in this study were not raised to market size and later developmental changes to metabolism could alter PFAS accumulation, the filets of juvenile red drum in this study did not bioaccumulate PFAS in amounts that would cause concern for human consumption.