To Örebro University

Background and aim: Diet and drinking water have been identified as major sources of PFAS exposure in humans. To accurately estimate exposure in the Swedish population, knowledge of background levels in foods are crucial. The study aims to increase knowledge of levels of PFOA, PFNA, PFHxS, and PFOS (PFAS4) in foods commonly consumed by the majority of Swedish consumers, to enable updated exposure estimations in small children, adolescents, and adults.

Material and methods: Food samples from the Swedish Market Basket 2022, including 16 food groups, were analysed for PFAS. Exposuree stimations in the Swedish population were performed using consumption data from three Swedish dietary surveys: Riksmaten adults (2010–11), Riksmaten adolescents (2016–17), and Riksmaten small children (2021–2023). Exposure scenarios for drinking water (4 ng PFAS4/L) and fish consumption (2–3 portions/week) were used. A drinking water consumption of 2 (adults, adolescents), 1.6 (4-year-olds), and 1.2 (1.5-year-olds) L per day was used, and a portion size of 150 (adults), 100 (adolescents), and 50 (small children) g for fish. All results are presented as lower bound.

Results: Detectable levels of PFAS4 were found in 3 of the 16 food groups, in lean fish (PFOA, PFNA, PFOS), fatty fish (PFOS), and eggs (PFOS). The mean PFAS4 concentration was 0.30 ng/g in lean fish, 0.08 ng/g in fatty fish, and 0.05 ng/g in eggs. The median exposure of PFAS4 from food in adult women and men was 0.12 and 0.10 ng/kg body weight (BW)/day (75 th percentile (p75), 0.22, 0.21), respectively. In 4-year-olds and adolescents, it was lower, medians 0.03–0.08 ng/kgBW/day (p75, 0.13–0.42), and in 1.5-year-olds, slightly higher, median 0.11 ng/kg BW/day (p75, 0.46). The proportion exceeding the TDI by EFSA (0.63 ng/kg BW/day) was decreasing by increasing age. In the small children 16–19% exceeded the TDI, whereas 1–4% of the adults and adolescents. When drinking water was added, the median exposure rose to 0.24 and 0.20 ng/kg BW/day for women and men, respectively, and to 0.16–0.27 ng/kg BW/day for adolescents. In 1.5-year-olds, median exposure was 0.55 ng/kg BW/day and in 4-year-olds 0.47 ng/kg BW/day. TDI exceeded in 3–11% of adults and adolescents and 33–41% of small children. Consuming fish 2–3 times/week, including drinking water, raised median exposure to 0.31 and 0.26 ng/kg BW/day for women and men, respectively, and to 0.25–0.39 ng/kg BW/day in adolescents. The median exposure was 0.83 and 0.64 ng/kg BW/day in 1.5- and 4-year-olds, in turn.

Conclusion: The highest exposure to PFAS4 was seen in 1.5-year-olds, and the lowest in adolescents. The median exposure in the scenario of fish consumption 2–3 times/week and drinking water included was below the TDI, except for the small children. The results stress thei mportance of updating levels in food in order to obtain accurate exposure estimations, as background exposure to PFAS4 is decreasing.