Non-targeted analysis of per- and polyfluorinated substances in consumer food packaging

Authors: STROSKI, KEVIN - Oak Ridge Institute For Science And Education (ORISE); Sapozhnikova, Yelena; TAYLOR, RAEGYN - Oak Ridge Institute For Science And Education (ORISE); Harron, Andrew

Submitted to: Chemosphere
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/23/2024
Publication Date: 5/24/2024
Citation: Stroski, K., Sapozhnikova, Y.V., Taylor, R., Harron, A.F. 2024. Non-targeted analysis of per- and polyfluorinated substances in consumer food packaging. Chemosphere. 360:142436. https://doi.org/10.1016/j.chemosphere.2024.142436.
DOI: https://doi.org/10.1016/j.chemosphere.2024.142436

Interpretive Summary: Per and polyfluoroalkyl substances (PFAS) are chemicals extensively used in many industrial and commercial applications, including food contact materials (FCMs). Over 10,000 PFAS chemicals exist, but only a small portion of them (~40) with available analytical standards is monitored. To solve this problem, the use of non-targeted approaches with high resolution accurate mass spectrometry (HRAM) is advantageous in discovering novel PFAS. In this study, we developed a new HRAM approach to identify PFAS not captured by the limited scope of targeted approaches. Several new PFAS chemicals were identified in food packaging samples from the US market, demonstrating the importance of non-targeted approach.

Technical Abstract: This study sought to develop non-targeted workflows using high-resolution accurate mass spectrometry (HRAMS) to investigate previously unknown PFAS in consumer food packaging samples. The samples of different food types which are composed of various materials were subjected to methanolic extraction, controlled migration with food simulants and total oxidizable precursor (TOP) assay. Developed workflows utilized many signatures unique to PFAS compounds such as a negative mass defect, diagnostic breakdown structures, as well as retention time prediction. Potential PFAS features were identified in all packaging studied, regardless of food and material types. Five tentatively identified compounds were confirmed with analytical standards: 6:2 fluorotelomer phosphate diester (6:2 diPAP) and one of its intermediate breakdown products 2H-perfluoro-2-octenoic acid (6:2 FTUCA), perfluoropentadecanoic acid (PFPeDA), perfluorohexadecanoic acid (PFHxDA) and perfluorooctadecanoic acid (PFOcDA). Longer perfluorocarboxylic acids including C17 and C19 to C24 were also found present within a foil sample. Due to their persistence and potentials for bioaccumulation the C9 to C¬20 acids were placed on the toxic substances list in Canada. Concentrations of 6:2 FTUCA ranged from 0.78 – 127 ng/g in methanolic extracts, and up to 6 ng/g in food simulant after 240 hours migration test. On average 8.5%, and at maximum 18%, of the TOP assay results were explained by oxidation of 6:2 FTUCA alone. The results from this study demonstrate the utility of using various HRMS methods for the determination of PFAS in consumer food packaging and highlights the need for more work to understand the full PFAS load of these products.