Per- and polyfluoroalkyl substances (PFAS) in aquaculture feeds and potential dietary exposure to and from aquaculture fish

The "forever chemicals" per- and polyfluoroalkyl substances (PFAS) have been measured in wild caught fish, but few studies have examined PFAS in aquaculture. This study aims to quantify PFAS in commercial aquaculture feeds, quantify PFAS in fillets and livers of aquaculture fish fed commercial diets, and estimate human dietary exposure of PFAS through consumption of aquaculture fish. Thirteen commercial feeds were analyzed for 29 PFAS. Fifteen PFAS were detected with perfluorooctanesulfonic acid (PFOS) detected in all feeds. A 63-day feeding trial on juvenile red drum (Sciaenops ocellatus) fed two different feeds at three ration levels was conducted. Only PFOS was detected in the fillets and livers, and fish given the higher PFOS diet exhibited a higher percentage of detection in their fillets (70.8 %; mean = 0.09 ng/g) compared to fish given the lower PFOS diet (0 %). There was a significant difference in size between the feed groups (p-value < 0.0001), suggesting a possible growth dilution effect. PFOS did not differ among rations, and levels in the fillets did not exceed EFSA guidelines. This study provides baseline data on dietary contribution of PFAS to and from aquaculture fish and allows for informed safe consumption recommendations to safeguard human health.