Characterization and dermal bioaccessibility of residual- and listed PFAS ingredients in cosmetic products

Abstract

As a large group of chemicals with diverse properties, per- and polyfluoroalkyl substances (PFAS) have found extensive application throughout consumer products, including cosmetics. Little is known about the importance of dermal uptake as a human exposure pathway for PFAS. Here we investigate a suite of listed-ingredient and residual PFAS in cosmetic products, along with their dermal bioaccessibility using <i>in vitro</i> incubations with artificial sweat. Concentrations of volatile listed ingredients (including cyclic perfluorinated alkanes, perfluorinated ethers, and polyfluorinated silanes) in three products ranged from 876-1323 μg g^-1, while polar listed ingredients (<i>i.e.</i>, polyfluoroalkyl phosphate esters [PAPs]) in a single product occurred at up to 2427 μg g^-1 (6 : 2/6 : 2 diPAP)). Residual perfluoroalkyl carboxylic acids (PFCAs) were also measured at concentrations ranging from 0.02-29 μg g^-1. When listed ingredients were included, our targeted analysis accounted for up to 103% of the total fluorine, while highlighting ambiguous and/or incorrect International Nomenclature of Cosmetic Ingredient (INCI) names used in several products. Bioaccessibility experiments revealed that residual PFCAs readily partitioned to artificial sweat (bioaccessible fractions ranging from 43-76% for detectable substances) while listed ingredients (<i>i.e.</i>, PAPs and neutral/volatile PFAS) displayed negligible partitioning. This work provides new insight into the occurrence of PFAS in cosmetic products, while furthering our understanding on their mechanisms of dermal uptake.