Chickens’ eggs and the livers of farm animals as sources of perfluoroalkyl substances

Abstract

Introduction: This study focuses on perfluoroalkyl substance (PFAS) content in chickens’ eggs and the livers of farmanimals. Material and Methods: Chickens’ eggs (n = 25) and the livers of cows (n = 10), chickens (n = 7) and horses (n = 3) werecollected from various regions of Poland. Samples were analysed using the isotope dilution technique with liquid chromatographycoupled with tandem mass spectrometry (LC-MS/MS). Results: The mean lower bound (LB) sum of four PFAS (∑4 PFAS)concentrations (perfluorooctanesulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA) andperfluorohexanesulfonic acid (PFHxS)) were the highest in cows’ livers (0.52 μg/kg) and much lower in chickens’ (0.17 μg/kg)and horses’ livers (0.13 μg/kg) and chickens’ eggs (0.096 μg/kg). The ratio of ∑4 PFASs to the limits set by Commission Regulation(EU) 2023/915 was <7% for liver and <6% for eggs. Linear PFOS was the compound with the highest detection frequency (8% ineggs and 48% in all livers). In cows’ livers it was detected in 80% of samples. The estimated exposure to LB ∑4 PFASsvia consumption of liver tissue from farm animals (assuming 50 g and 100 g portions) was <52% of the tolerable weekly intake(TWI) for children and <17% of the TWI for adults. Dietary intake via the average portion of three eggs led to low exposure of<15% for children and <5% for adults. Conclusion: Neither eggs nor the livers of chickens or horses as analysed in this study aresignificant sources of PFASs, while cows’ livers might contribute significantly to a child’s overall dietary intake. Furtherinvestigation of PFOS in farm animal livers should be conducted