Nonpolymeric Per- and Polyfluoroalkyl Substances (PFAS) and Side-Chain Fluorinated Polymers in Canadian Building Products

To understand if exterior building products are a source of perfluoroalkyl and polyfluoroalkyl substances (PFAS) to the environment, we measured PFAS in 145 samples of paints, sealers, and textiles, mostly intended for exterior use. We first developed a combined one and two-dimensional diffusion-ordered spectroscopy (1D and 2D-DOSY) fluorine nuclear magnetic resonance (¹⁹F NMR) method to characterize and quantify side-chain fluorinated polymers (SCFPs) and nonpolymeric PFAS. Results showed that 36% (22/61), 24% (13/54), and 70% (21/30) of tested paints, sealers, and textiles contained total organic fluorine (TOF) at 0.1-16.1, 0.4-2488, and 0.34-74.0 μmol/g, respectively. Paints mainly contained 6:2 fluorotelomer (FT) and aromatic-CF₃ nonpolymeric PFAS, while sealers also contained 6:2 FT SCFPs and perfluorobutane sulfonyl fluoride (PBSF)-based PFAS. Textiles contained 6:2 FT, 8:2 FT, and PBSF-based PFAS indicative of SCFPs. Advanced mass spectrometry methods revealed that paints and sealers with 6:2 FT nonpolymers mainly contained 6:2 fluorotelomer phosphate mono-, di-, and triesters (6:2 mono-, di-, and triPAPs) and 6:2 FT dipyrophosphate, while textiles primarily contained n:2 fluorotelomer alcohols (n:2 FTOH, n = 6, 8) or N-methyl perfluorobutane sulfonamide alcohol (MeFBSE). Based on the PFAS found in these products and the recommendation to reapply the coatings to protect exterior/interior surfaces and the replacement of exterior textiles, these results indicate that building products likely contribute polymeric and nonpolymeric PFAS to the environment.