A source-based framework to estimate the annual load of PFAS in municipal wastewater

• Published in: The Science of the total environment 2024-04, Vol.920, p.170997-170997, Article 170997
• Main Authors: Krlovic, N., Saracevic, E., Derx, J., Gundacker, C., Krampe, J., Zessner, M., Zoboli, O.
• Format: Article
• Language: English
• Subjects: Emissions; Influent; Mass balance; MFA; Pathways; Urban pollution
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2024.170997

Per- and Polyfluoroalkyl substances (PFAS) are a class of persistent chemicals, whose impact has been observed in various environmental compartments. Wastewater treatment plants (WWTPs) are considered a major emission pathway of PFAS, specifically in the context of the aquatic environment. The goal of this study was to develop a compartmentalized, source-based load estimation model of 7 PFAS within the municipal wastewater influent. Consumer statistics, data from literature on PFAS concentrations and release during use, and specific sampling activities for environmental flows in the related city were used to estimate per capita emission loads. Model results were compared with loads obtained through the monitoring campaign at the municipal WWTP influent. A wide range of discrepancies (≈5 % to ≈90 %) between loads observed in the WWTP influent and source based model estimates was noticed. The loads less accounted by the model were associated with sulfonic acids (PFSAs), whereas for carboxylic acids (PFCAs) most of the observed loads could be reasonably explained by the model, with even an overestimation of nearly 5 % noted for PFNA. Higher heterogeneity in sources was observed in the PFCA group, with a noticeable dominance in the share of consumer products. PFSAs had less of a consumer product input (