Discovery of 40 Classes of Per- and Polyfluoroalkyl Substances in Historical Aqueous Film-Forming Foams (AFFFs) and AFFF-Impacted Groundwater

Abstract

Aqueous film-forming foams (AFFFs), containing per- and polyfluoroalkyl substances (PFASs), are released into the environment during response to fire-related emergencies. Repeated historical applications of AFFF at military sites were a result of fire-fighter training exercises and equipment testing. Recent data on AFFF-impacted groundwater indicates that ∼25% of the PFASs remain unidentified. In an attempt to close the mass balance, a systematic evaluation of 3M and fluorotelomer-based AFFFs, commercial products, and AFFF-impacted groundwaters from 15 U.S. military bases was conducted to identify the remaining PFASs. Liquid chromatography quadrupole time-of-flight mass spectrometry was used for compound discovery. Nontarget analysis utilized Kendrick mass defect plots and a "nontarget" R script. Suspect screening compared masses with those of previously reported PFASs. Forty classes of novel anionic, zwitterionic, and cationic PFASs were discovered, and an additional 17 previously reported classes were observed for the first time in AFFF and/or AFFF-impacted groundwater. All 57 classes received an acronym and IUPAC-like name derived from collective author knowledge. Thirty-four of the 40 newly identified PFAS classes derive from electrochemical fluorination (ECF) processes, most of which have the same base structure. Of the newly discovered PFASs found only in AFFF-impacted groundwater, 11 of the 13 classes are ECF-derived, and the remaining two classes are fluorotelomer-derived, which suggests that both ECF- and fluorotelomer-based PFASs are persistent in the environment.

Serum perfluoroalkyl acids (PFAAs) and associations with behavioral attributes

“…This information may be helpful in informing larger studies about information that should be collected to identify determinants of exposure. The higher concentrations of the PFHxS in this population compared to NHANES suggest that exposure could be increasing, and may be related to levels now being detected in water sources throughout the country (Hu et al, 2016; Barzen-Hanson et al, 2017). Further studies should investigate the relationships between PFAS levels in drinking water and serum levels, taking into account personal behaviors that may determine exposure (e.g.…”

“…Given the longer half-life of PFHxS in serum, this may suggest past exposure to PFHxS in drinking water from sources that were recently contaminated. It is notable that many of the newly discovered PFASs in AFFF or AFFF-impacted drinking water could serve as precursors for PFHxS and/or PFHxA (Barzen-Hanson et al, 2017). For PFHxA, the high detection frequency of this PFAA compared to NHANES may be due to the fact that the laboratory where these samples were analyzed was recently established, resulting in very little blank contamination and low detection limits.…”

Reduction of a Tetrafluoroterephthalonitrile‐β‐Cyclodextrin Polymer to Remove Anionic Micropollutants and Perfluorinated Alkyl Substances from Water

“…[6] PFASs have been used in the formulations of thousands of consumer goods [19] and are present in aqueous film-forming foam formulations used to suppress aviation fires in training scenarios. [20,21] As ar esult, they have contaminated surface and ground waters near thousands of airports and military installations. [22,23] In 2018, the Environmental Working Group reported that over 16 million people in the United States were exposed to drinking water with PFAS concentrations exceeding 10 ng L À1 .…”

The Cyclodextrin-Perfluorinated Surfactant Host-Guest Complex: Fundamental Studies for Potential Environmental Remediation and Therapeutic Applications

“…PFASs aid solvation of tetrafluoroethylene monomers and PTFE itself so that emulsion polymerization can occur. The second application is as surfactants in aqueous film-forming foams (AFFF) (Prevedouros et al 2006, Barzen-Hanson et al 2017, Wang et al 2017. AFFF are used to stop hydrocarbon fires, by coating the surface of the hydrocarbon with PFASs to prevent oxygen from reacting with the hydrocarbon.…”

“…AFFF are used to stop hydrocarbon fires, by coating the surface of the hydrocarbon with PFASs to prevent oxygen from reacting with the hydrocarbon. AFFF have been extensively used by the military, especially in air craft hangers and air craft carriers, though they are also used in commercial airports (Barzen-Hanson et al 2017). The third application of PFASs is in various consumer products with water-, grease-, or stain-repellant properties (Prevedouros et al 2006, D'Hollander et al 2010, Schaider et al 2017.…”