Occurrence of PFAS in Lyon soils: contribution and impact of industrial activities

Abstract

As the environmental impact of per- and polyfluoroalkyl substances (PFAS) increases, understanding their deposition to soils near chemical industries is vital to mitigate health and ecological risks. Lyon (France) is a hub of chemical production and faces concerns about PFAS releases into the environment. This study assessed the extent of PFAS deposition from chemical industries located in central Lyon to different parts of Lyon. Through a target analysis using UHPLC-MS, we investigated the concentration of 80 PFAS in 215 Lyon soil samples collected around a fluoropolymer industrial complex. PFAS contamination of eggs in Lyon has been reported by local public health; hence, we evaluated PFAS in soils from a few selected chicken-feeding areas and free-range chicken eggs. High PFAS concentrations (3.8–175 μg kg⁻¹) were observed in soils near fluorochemical industries, with levels declining as distance from the industrial site increased. Long-chain PFCAs (C ≥ 8) and PFSAs (C ≥ 6) showed high detection rates (78–100%), with PFUnDA (0.05–106 μg kg⁻¹), PFTrDA (0.03–47.6 μg kg⁻¹), PFOS (0.1–32.6 μg kg⁻¹), PFHxS (0.03–23.7 μg kg⁻¹), PFNA (0.02–13.4 μg kg⁻¹) and PFOA (0.05–6.8 μg kg⁻¹), being the predominant PFAS. The ∑14 PFAS detected in soils from chicken-feeding areas ranged from 3.3–10.5 μg kg⁻¹ and 2.1–19.1 μg kg⁻¹ in eggs. This confirmed that the chickens are exposed to PFAS from the surrounding soils and other sources through their diet and foraging. Generally, the detection of elevated levels of PFNA, PFUnDA, and PFTrDA suggests an industrial input from the production of Surflon® at the Pierre-Bénite site. A significant negative correlation (p-value < 0.001) was observed between PFAS concentrations across the zones and their distance from the chemical industry. The variability in PFAS distribution may be influenced by wind direction, which has likely transported airborne PFAS from its source near the industrial complex and extending towards other parts.