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

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 6:2 fluorotelomer methacrylate (FTMAc) and 6:2 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 6:2 FTMAc and FTOH. The use of PFAS in food packaging such as “compostable” bowls represents a regrettable substitution of single-use plastic food packaging.

Per- and polyfluoroalkyl substances (PFAS) are used globally and comprise more than 4700 individual compounds. (1,2) They have been intentionally added to food packaging for decades to confer grease and water repellency. PFAS are inherently persistent, and many are mobile, bioaccumulative, and/or toxic. (3−6) As such, their use in food packaging could represent a significant issue in terms of direct human exposure and end-of-life environmental pollution. (3,5−9) On December 20, 2022, the Government of Canada prohibited the manufacturing or import of single-use plastics, including “single-use plastic foodservice ware” such as polystyrene and oxo-degradable plastic clamshell containers, lidded containers, boxes, and bowls. (10)This regulation, and a subsequent Canadian regulation that will restrict the use of these single-use plastics entirely by December 2023, will likely lead to greater use of plant fiber-based food packaging alternatives, to which PFAS may be added to achieve grease- and water-repellency. (11) If so, this would represent a regrettable substitution of trading one harmful option for another.

Source: https://pubs.acs.org/doi/10.1021/acs.estlett.2c00926?ref=pdf