Recent Developments and Challenges in Testing Per- and Polyfluoroalkyl Substances (PFAS) in Food of Animal Origin

Analysis of per- and polyfluoroalkyl substances (PFAS) in food is important to ensure safe food consumption, however most existing analytical methods focus on only a small group of PFAS analytes. We developed and validated a new method for analysis of 74 PFAS ranging across 15 different groups including legacy PFAS, short-chain alternatives, precursors and breakdown products in food of animal origin. The method was based on “quick, easy, cheap, effective, rugged, safe, efficient, and robust” (QuEChERSER) mega-method and LC-MS/MS analysis. Validation was performed at, above and below maximum levels set by the European Food Safety Authority (EFSA) in beef, chicken, pork, catfish, liquid egg, and powdered egg samples. Acceptable recovery was obtained for 84% - 97% analytes. The method was further validated with NIST standard reference materials (SRMs) 1946 and 1947 resulting in accuracy of 71% - 112%. The validated method was applied to investigate the occurrence and levels of PFAS in meat, poultry, catfish and eggs. We tested 86 food samples purchased from grocery stores in the US. For beef, chicken, pork, and eggs, 10 samples of each conventional and organic production were tested. No PFAS were detected in eggs, chicken, and pork samples. PFOS was found in beef samples, and 12 PFAS were found in catfish. The measured concentrations were below the EFSA maximum levels and tolerable weekly intake. The information generated on PFAS occurrence and levels in the US foods helps to estimate the contribution of diet to overall human exposure to PFAS.