Per- and Polyfluoroalkyl Substances in Canadian Fast Food Packaging.

ABSTRACT

A suite of analytical techniques was used to obtain a comprehensive picture of per- and polyfluoroalkyl substances (PFAS) in selected Canadian food packaging used for fast foods (n = 42). Particle-induced gamma ray emission spectroscopy revealed that 55% of the samples contained <3580, 19% contained 3580-10 800, and 26% > 10 800 µg F/m2. The highest total F (1 010 000-1 300 000 µg F/m2) was measured in molded "compostable" bowls. Targeted analysis of 8 samples with high total F revealed 4-15 individual PFAS in each sample, with 62 fluorotelomer methacrylate (FTMAc) and 62 fluorotelomer alcohol (FTOH) typically dominating. Up to 34% of the total fluorine was released from samples after hydrolysis, indicating the presence of unknown precursors. Nontargeted analysis detected 22 PFAS from 6 different groups, including degradation products of FTOH. Results indicate the use of side-chain fluorinated polymers and suggest that these products can release short-chain compounds that ultimately can be transformed to compounds of toxicological concern. Analysis after 2 years of storage showed overall decreases in PFAS consistent with the loss of volatile compounds such as 62 FTMAc and FTOH. The use of PFAS in food packaging such as "compostable" bowls represents a regrettable substitution of single-use plastic food packaging.