Ultra-Short-Chain PFASs in the Sources of German Drinking Water: Prevalent, Overlooked, Difficult to Remove, and Unregulated

• Published in: Environmental science & technology Vol. 56; no. 10; pp. 6380 - 6390
• Main Authors: Neuwald, Isabelle J., Hübner, Daniel, Wiegand, Hanna L., Valkov, Vassil, Borchers, Ulrich, Nödler, Karsten, Scheurer, Marco, Hale, Sarah E., Arp, Hans Peter H., Zahn, Daniel
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 17.05.2022
• Subjects: Biological Assay; Contaminants in Aquatic and Terrestrial Environments; Contamination; Drinking Water; Environmental chemistry; Environmental Monitoring; environmental science; Europe; Fluorine; Fluorocarbons - analysis; Perfluoro compounds; Perfluoroalkyl & polyfluoroalkyl substances; Perfluorocarbons; Perfluorochemicals; technology; Water analysis; Water Pollutants, Chemical - analysis; Water sampling; Europe; bis(trifluoromethylsulfonyl)imide (NTf2); trifluoroacetate (TFA); sum parameters; monitoring; perfluoropropanoate (PFPrA); hexafluoroisopropanol (HFIP); tris(pentafluoroethyl)trifluorophosphate (FAP); trifluoromethanesulfonate (TFMS)
• ISSN: 0013-936X; 1520-5851; 1520-5851
• DOI: 10.1021/acs.est.1c07949

Per- and polyfluoroalkyl substances (PFASs) have been a focal point of environmental chemistry and chemical regulation in recent years, culminating in a shift from individual PFAS regulation toward a PFAS group regulatory approach in Europe. PFASs are a highly diverse group of substances, and knowledge about this group is still scarce beyond the well-studied, legacy long-chain, and short-chain perfluorocarboxylates (PFCAs) and perfluorosulfonates (PFSAs). Herein, quantitative and semiquantitative data for 43 legacy short-chain and ultra-short-chain PFASs (≤2 perfluorocarbon atoms for PFCAs, ≤3 for PFSAs and other PFASs) in 46 water samples collected from 13 different sources of German drinking water are presented. The PFASs considered include novel compounds like hexafluoroisopropanol, bis­(trifluoromethylsulfonyl)­imide, and tris­(pentafluoroethyl)­trifluorophosphate. The ultra-short-chain PFASs trifluoroacetate, perfluoropropanoate, and trifluoromethanesulfonate were ubiquitous and present at the highest concentrations (98% of sum target PFAS concentrations). “PFAS total” parameters like the adsorbable organic fluorine (AOF) and total oxidizable precursor (TOP) assay were found to provide only an incomplete picture of PFAS contamination in these water samples by not capturing these highly prevalent ultra-short-chain PFASs. These ultra-short-chain PFASs represent a major challenge for drinking water production and show that regulation in the form of preventive measures is required to manage them.