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This paper reports the electrochemical treatment of poly-and perfluoroalkyl substances (PFASs) in the effluent from an industrial wastewater treatment plant (WWTP). While most of the previous research focused on the electrochemical degradation of perfluorooctanoic acid and perfluorooctane sulfonate in model solutions, this work studies the simultaneous removal of 8 PFASs at environmentally relevant concentrations in real industrial emissions, which also contained organic matter and inorganic anions. The overall PFASs content in the WWTP effluent was 1652 µg/L, which emphasized the need to develop innovative technologies for the management of PFASs emissions. 6:2 fluorotelomer sulfonamide alkylbetaine (6:2 FTAB) and 6:2 fluorotelomer sulfonate (6:2 FTSA) were the major contributors (92% w/w) to the overall PFASs content, that also contained significant amounts of short-chain perfluorocarboxylic acids (PFCAs). Using a boron doped diamond (BDD) anode of 0.0070 m 2 , the effluent (2 L) was treated by applying a current density of 50 mA/cm 2 for 10 hours, that resulted in 99.7% PFASs removal. The operation at lower current densities (5 and 10 mA/cm 2 ) evidenced the initial degradation of 6:2 fluorotelomers into perfluoroheptanoic and perfluorohexanoic acids, that were later degraded into shorter chain PFCAs. The high TOC removal, >90%, and the fluoride release revealed that PFASs mineralization was effective. These results highlight the potential of the electrochemical technology for the treatment of PFASs contained in industrial wastewaters, which nowadays stands as the main source of this group of persistent pollutants into the environment.

Perfluorooctane sulfonamidoethanol based phosphate diester (SAmPAP) is a potential perfluorooctanesulfonate (PFOS) precursor. To examine whether SAmPAP exposure would result in fish contamination by perfluoroalkyl and polyfluoroalkyl substances (PFASs), juvenile Eurasian perch were dietarily exposed to this compound (dosed group) or exposed to the same tank water but fed control feed (control group). SAmPAP and metabolites were monitored in the muscle, liver, and serum during the 45-day exposure phase and 35-day depuration phase. SAmPAP was only detected in the dosed group and the absorption efficiency (0.04-2.25%) was very low, possibly related to its low bioavailability in the gastrointestinal tract, steric constraints in crossing biological membranes, and clearing by enterohepatic circulation. Although SAmPAP was biotransformed and eliminated at a slow rate (t > 18 days), its biomagnification factor was low. The observed metabolites in fish were N-ethyl perfluorooctane sulfonamidoacetic acid, perfluorooctane sulfonamidoacetic acid, perfluorooctane sulfonamide, and PFOS. Considering that SAmPAP was the only source of PFASs in the tanks, the occurrence of metabolites indicates that SAmPAP could be biotransformed in fish and contribute to PFOS bioaccumulation. However, levels of metabolites were not significantly different in the dosed and control groups, indicating that metabolite excretion followed by re-exposure to these metabolites from water was the main uptake route.

The occurrence of seven perfluoroalkyl carboxylates (PFCAs) and three perfluoroalkyl sulfonates (PFASs) was studied in raw- and treated-water samples from public water systems. Two sampling campaigns were performed during the summer of 2009 and in June 2010. Sampling was equally distributed across the 100 French departments. In total, 331 raw-water samples and 110 treated-water samples were analyzed during this study, representing approximately 20% of the national water supply flow. Concentrations of perfluorinated compounds (PFCs) were determined using automated solid-phase extraction and liquid chromatography-tandem mass spectrometry. In raw-water samples, the highest individual PFC concentration was 139 ng/L for perfluorohexanoic acid (PFHxA). The sum of all of the determined components was >100 ng/L at three sampling points (199, 117, and 115 ng/L). Of the investigated PFCs, perfluorooctane sulfonate (PFOS), perfluorohexane sulfonate (PFHxS), perfluorooctanoic acid (PFOA), and PFHxA predominated (detected in 27%, 13%, 11%, and 7% of samples, respectively). Geographical variability was observed, with departments crossed by major rivers or with high population densities being more affected by PFC contamination. Compared with raw water, short-chain PFCAs, but not PFASs, were found in higher abundance in treated water. This difference suggests a relative effectiveness of certain water treatments for the elimination of PFASs but also a possible degradation of PFCA precursors by water-treatment processes. Our investigations did not show any heavily contaminated sites. In treated-water samples, the highest individual PFC concentration was 125 ng/L for PFHxA. The sum of all of the determined components was >100 ng/L at one sampling point (156 ng/L). The values observed for PFOS and PFOA in drinking water were not greater than the health-based drinking-water concentration protectives for lifetime exposure that have been defined for other countries.