Per- and polyfluoroalkyl substances (PFASs) are a large family of thousands of chemicals, many of which have been identified using nontargeted time-of-flight and Orbitrap mass spectrometry methods. Comprehensive characterization of complex PFAS mixtures is critical to assess their environmental transport, transformation, exposure, and uptake. Because 21 tesla (T) Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR MS) offers the highest available mass resolving power and sub-ppm mass errors across a wide molecular weight range, we developed a nontargeted 21 T FT-ICR MS method to screen for PFASs in an aqueous film-forming foam (AFFF) using suspect screening, a targeted formula database (C, H, Cl, F, N, O, P, S; ≤865 Da), isotopologues, and Kendrick-analogous mass difference networks (KAMDNs).
View Article and Find Full Text PDFSoil and groundwater from an aqueous film-forming foam (AFFF)-impacted site were sampled at high resolution ( = 105 for soil, = 58 for groundwater) and analyzed for an extensive list of anionic, zwitterionic, and cationic poly- and perfluoroalkyl substances (PFASs). Spatial trends for perfluoroalkyl acids and many precursors enabled a better understanding of PFAS composition, transport, and transformation. All PFASs without analytical standards were semi-quantified.
View Article and Find Full Text PDFTransport of poly- and perfluoroalkyl substances (PFAS) at aqueous film-forming foam (AFFF)-impacted sites is limited by various processes that can retain PFAS mass within the source area. This study used concentration data obtained via a high-resolution sampling and analytical protocol to estimate the PFAS mass distribution in source and downgradient areas of a former firefighter training area. The total PFAS mass present at the site was approximately 222 kg, with 106 kg as perfluoroalkyl acids (PFAAs) and 116 kg as polyfluorinated precursors.
View Article and Find Full Text PDFDevelopment of on-site treatment strategies for PFAS-containing investigation derived waste (IDW) will decrease the potential for secondary release following off-site disposal, lower disposal costs, and promote more effective long-term management of PFAS-laden waste. Herein, we report the application of a simple, drop-in treatment that utilizes one of two PFAS sorbents: bituminous granular activated carbon (GAC) or strong base anion exchange resin (IX) and a small circulation pump to adsorb and concentrate PFAS impacted mass from liquid IDW collected from two sites with disparate water chemistries and synthetic IDW amended with PFAS-containing aqueous film forming foam (AFFF). Bench scale intermittent circulation experiments revealed that bituminous granular activated carbon (GAC, 0.
View Article and Find Full Text PDFPoly- and perfluoroalkyl substances (PFASs) derived from aqueous film-forming foam (AFFF) are increasingly recognized as groundwater contaminants, though the composition and distribution of AFFF-derived PFASs associated with soils and subsurface sediments remain largely unknown. This is particularly true for zwitterionic and cationic PFASs, which may be incompletely extracted from subsurface solids by analytical methods developed for anionic PFASs. Therefore, a method involving sequential basic and acidic methanol extractions was developed and evaluated for recovery of anionic, cationic, and zwitterionic PFASs from field-collected, AFFF-impacted soils.
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