Fluorinated alkyl substances and technical mixtures used in food paper-packaging exhibit endocrine-related activity in vitro
Abstract
Migration of chemicals from packaging materials to foods may lead to human exposure. Polyfluoroalkyl substances (PFAS) can beused in technical mixtures (TMs) for use in food packaging of paper and board, and PFAS have been detected in human serum andumbilical cord blood. The specific structures of the PFAS in TMs are often unknown, but polyfluorinated alkyl phosphate esters(PAPs) have been characterized in TMs, food packaging, and in food. PAPs can be metabolized into fluorotelomer alcohols (FTOHs)and perfluoroalkyl carboxylic acids (PFCAs). Some PFAS have endocrine activities, highlighting the need to investigate these effects.Herein, we studied the endocrine activity of less characterized PFAS, including short-chain PFCAs and FTOHs, PAPs, and TMs ofunknown chemical composition. Long-chain PFCAs were also included. We applied seven assays covering effects on estrogen, gluco-corticoid, androgen, and peroxisome proliferator-activated receptor (PPAR) activity, as well as steroidogenesis in vitro and ex vivo. Ingeneral, PAPs, FTOHs, TMs, and long-chain PFCAs showed estrogenic activity through receptor activation and/or increasing 17b-estradiol levels. Furthermore, short- and long-chain PFCAs activated PPARaand PPARc. Collectively, this means that (i) PAPs,FTOHs, and PFCAs exhibit endocrine activity through distinct and sometimes different mechanisms, (ii) two out of three tested TMsexhibited estrogenic activity, and (iii) short-chain FTOHs showed estrogenic activity and short-chain PFCAs generally activate bothPPARaand PPARcwith similar potency and efficacy as long-chain PFCAs. In conclusion, several new and divergent toxicologicaltargets were identified for different groups of PFAS.