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While aqueous film forming foam (AFFF) release has been known to result in environmental contamination with perfluoroalkyl and polyfluoroalkyl substances (PFASs) for over fifteen years, identities of individual PFASs in AFFFs have been largely unknown, proprietary information. Using mixed-mode ion exchange solid phase extraction (SPE), high resolution mass spectrometry (HR-MS), quadrupole time-of-flight (qTOF) tandem mass spectrometry (MS/MS), and liquid chromatography (LC)-MS/MS, 103 individual PFASs were identified in AFFFs and surfactant concentrates, including multiple chain-length congeners. Aerobic wastewater treatment plant sludge biodegradation of two AFFF components, 6:2 fluorotelomer sulfonamide alkylbetaine (FTAB) and alkylamine (FTAA), was investigated revealing biodegradation to short-chain perfluoroalkyl carboxylates (PFCAs) and known PFCA precursors. Additional degradation products were also identified, including 6:2 fluorotelomer sulfonamide (FTSAm) as a degradation product of both 6:2 FTAB and 6:2 FTAA, and six additional degradation products of 6:2 FTAA. A survey of selected Canadian surface waters for AFFF-related PFASs using SPE and LC-MS/MS revealed that several AFFF-related PFASs could be detected in urban and AFFF-impacted surface waters. These included FTABs and fluorotelomer betaines (FTBs), which were the fluorotelomer PFASs with the highest maximum concentrations. Other PFASs, such as perfluorohexane sulfonamide (FHxSA), 6:2 FTSAm, and 6:2 fluorotelomer mercaptoalkylamido sulfonate sulfone (FTSAS-SO2) were identified in some samples. Extraction and analysis of sediment from an AFFF-impacted river and batch sorption experiments with 6:2 FTAA and 6:2 FTAB in an agricultural soil provide preliminary insights into sorption behaviour of AFFF components, where longer chain-length FTBs were apparently more sorptive than shorter chain-lengths and 6:2 FTAA was more sorptive than 6:2 FTAB. This work is significant in identifying numerous PFASs found in AFFF that require further research in ... |