Comprehensive Validation of the Adsorbable Organic Fluorine Analysis and Performance Comparison of Current Methods for Total Per- and Polyfluoroalkyl Substances in Water Samples

Abstract

Per- and polyfluoroalkyl substances (PFASs) are widely detected in the environment, while a large number of them cannot be identified and/or quantified by current analytical methods. As a surrogate total PFAS analysis, the adsorbable organic fluorine (AOF) method was improved and validated in this study. The improved method has limits of detection and quantification of 300 and 400 ng/L, respectively, more sensitive than the previously reported AOF methods. AOF recovery for 29 individual PFASs ranged 53–113%, while three short-chain PFASs yielded lower recovery (19–39%) due to low adsorption efficiency. Recovery for PFAS mixtures in different environmental water matrices was 64–84%, and was negligibly impacted by the presence of fluoride, dissolved organic matter, or other matrix constituents. The validated method was applied to different environmental water samples, and AOF data were compared to results from other total PFAS analyses, including total fluorine, extractable organic fluorine, total oxidizable precursors, and summed individual PFASs. The fluorine contents from targeted PFAS analysis only contributed 0.4–29% of AOF concentrations in all except two samples, indicating the significance of AOF for estimating unknown PFAS concentrations, screening PFAS contamination, and assessing PFAS exposure.

Characterization of Per- and Polyfluorinated Alkyl Substances Present in Commercial Anti-fog Products and Their In Vitro Adipogenic Activity

“…All anti-fog products and the 6:2 FTEO commercial formulation were analyzed for TOF using previously published methods . TOF in this context refers to organic-bound fluorine or organofluorine.…”

“…All anti-fog products and the 6:2 FTEO commercial formulation were analyzed for TOF using previously published methods. 74 TOF in this context refers to organic-bound fluorine or organofluorine. The fluorine contents in the four anti-fog sprays and the 6:2 FTEO formulation were diluted by methanol and water and then analyzed in triplicates by a Mitsubishi AQF-2100H furnace system.…”

Digging deep—implementation, standardisation and interpretation of a total oxidisable precursor (TOP) assay within the regulatory context of per- and polyfluoroalkyl substances (PFASs) in soil

“…1). Aside from adsorbable organic fluorine (AOF) [41][42][43][44][45] for soil leachates, only extractable organic fluorine (EOF) [46,47], TOP assay [42,48,49], and 19 F nuclear magnetic resonance (NMR) (BWPLUS project FluorTECH, unpublished results, 2021) have been applied quantitatively for soil samples or sediments and thus are considered here. The highest selectivity is linked to the non-destructive 19 F NMR analysis giving spectral information on the chemical structure of the organofluorine chemicals, including non-ionic substances.…”

Development of a standardized adsorbable organofluorine screening method for wastewaters with detection by combustion ion chromatography

“…[15][16][17] Han and colleagues reported a limit of detection (LOD) of 300 ng L À1 using activated carbon, however, 300 mL sample volumes were used to reach those detection limits. 28 While increasing our sample size would lower our MDL, adsorption of larger sample volumes will likely decrease the recovery of the short-chain organouorine compounds due to break through on the GAC especially in sample matrices other than deionized water where natural organic matter will compete for adsorption onto the GAC. In addition, loading more than 100 mL of wastewaters containing signicant total suspended solids is unlikely due to clogging of the GAC columns.…”