Sarah E Prebihalo, Jordan Escavage, Luke K Ackerman, Iris Yourick, Katherine S Carlos
Food contact paper (FCP) coated with grease-proofing and water-resistant polymers were a potential source of dietary exposure to per- and polyfluoroalkyl substances (PFAS). While there were a variety of polymer types, historically, fluorotelomer-based acrylate polymers have been a common subset; first, with long-chain PFAS (≥ C8), phased out in 2011, and later, short-chain (≤C7) PFAS. Following FDA findings that 6:2 fluorotelomer alcohol (6:2 FTOH) has the potential for bioaccumulation in rodent models, manufacturers made voluntary commitments to phase out the use of 6:2 FTOH, concluding in 2023. To monitor this phase out, FDA developed screening methods using Direct Analysis in Real Time-Isotope Dilution-High Resolution Mass Spectrometry (ID-DART-HRMS) and Fluorine-19 nuclear magnetic resonance spectroscopy (19F NMR). To further monitor the phase out, a quantitative gas chromatography mass spectrometry (GC-MS) method was developed using hydrolysis of FCP. The method was then single-laboratory validated for a variety of FCP types. The method detection limits (MDL) were reported as 99 ng/g, 118 ng/g, 176 ng/g for tissue paper, moulded fibre, and paperboard, respectively. Twelve (12) market samples were analysed using the GC-MS method and nine (9) were found to contain 6:2 FTOH above the MDL, ranging from 0.3 µg/g to ∼1700 µg/g.