Integrated target and suspect screening approach for PFAS monitoring in drinking water: A case study from the Basque Country (Spain)
Year: 2026
Type: article
Abstract: • Optimized and validated HRMS method for 42 PFAS in drinking water at ng/L levels • PFAS were detected in all the basins studied in the Urola and Goierri regions of the Basque Country, and some concentrations increased after the DWTP treatment • Estimated daily PFAS intake shows PFCAs, PFSAs and FTCAs as main contributors • Hazard index values remain low (HI < 0.5) for the study population • Complementary analysis through SNTS revealed 23 additional fluorinated compounds The widespread use of PFAS has led to their pervasive presence in the environment, with contamination levels shaped by both human and natural factors. Drinking water is a primary exposure route, since Drinking Water Treatment Plants (DWTPs) are unable to efficiently remove PFAS or, in some cases, increase PFAS levels after treatment. In this study, PFAS were analyzed in 29 water samples including raw, treated and tap water from a children’s cohort living place in Basque Country (INMA project, Spain), a population previously reported to accumulate PFAS. Analysis was conducted using high-performance liquid chromatography with high-resolution mass spectrometry, achieving detection limits of 0.002–1.2 ng/L and method quantification limits of 0.008–3.8 ng/L for 42 PFAS, respectively. Method performance met new PFAS regulatory standards, with satisfactory precision (2–29%) and recovery rates (78–129% across) confirmed by Water and Environmental Chemistry proficiency testing scheme (Aquacheck). The whole analytical method was applied in three different basins obtaining measurable PFAS levels in all sampling points. Nevertheless, total PFAS concentrations were below the maximum PFAS contaminant levels (total PFAS = 500 ng/L) set by the EU Drinking Water Directive. The assessment of the 3 water basins at consecutive years (2023 and 2024) showed comparable PFAS levels. However, in some cases PFAS levels increased after treatment in the DWTPs suggesting a source of PFAS contamination. Estimated daily intake for different PFAS families was also calculated, obtaining very different profiles, being PFCAs, PFSAs and FTCAs the main contributors to the total PFAS intake through drinking water. Comparison of drinking water and plasma data revealed no direct correlations, suggesting additional sources contribute to the PFAS burden in plasma. Finally, hazard indexes showed overall low hazard (HI < 0.5) in the study area. On the other hand, suspect screening results showed the presence of 23 fluorinated features at different identification levels (2a to 4). The detected families were fluorinated sulfonic acids, quinolines, phosphonates, ketones, carboxylic acids, aldehydes, alcohols and esters suggesting that the current regulations and monitoring programs may be insufficient.
Language: English
Subfield: Environmental Chemistry
Field: Environmental Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,400
OpenAlex ID: W7127056946