Development of a procedure based on dispersive solid phase extraction and LC-MS/MS for the analysis of perfluoroalkyl and polyfluoroalkyl substances in food contact materials

Abstract

To monitor per- and polyfluoroalkyl substances (PFAS) in food contact materials (FCMs), an LC-MS/MS method for the simultaneous detection of 35 PFAS was developed and validated in paper and plastic products. Chromatographic and mass spectrometry parameters, extraction solvents, matrix effects in details were studied. The impact of matrix effects on PFAS concentration was analyzed, revealing that the matrix enhancement effect was more significant for some PFAS with low concentrations. In order to eliminate the matrix effect and enhance detection accuracy, a straightforward pretreatment method combining methanol ultrasonic extraction with dispersive solid-phase extraction (d-SPE) was established. PFHpA, PFDA, PFTriDA, PFTeDA, PF-3,7-DMOA, HFPO-DA, PFHxS, PFHpS, PFOS, 4:2 FTS, 6:2 FTS, 8:2 FTS, 10:2 FTS, and 6:2 diPAP required further d-SPE extraction with PSA, and other substances could be directly extracted by methanol ultrasonic treatment. The recoveries of the established method for all compounds ranged from 62.40 to 135.80%, with a relative standard deviation (RSD) of 0.15% to 16.81%. The limit of quantitation was between 0.005 and 0.02 mg·kg⁻¹. The method was applied to detect PFAS in 119 FCMs, resulting in the identification of 15 PFAS.