Mapping per- and polyfluoroalkyl substances contamination in England's surface waterbodies: Urban water cycle pathways and governance challenges

Abstract

Per- and polyfluoroalkyl substances (PFAS) contamination has emerged as a major international environmental and regulatory challenge, with PFAS increasingly detected across freshwater systems worldwide. However, in countries with limited PFAS manufacturing, such as England, it remains unclear whether surface waterbodies contamination reflects diffuse consumer-driven pollution, sectoral pressures, or dominant point-source pathways of PFAS pollution, such as Wastewater Treatment Works (WWTWs). In this study, we address this gap by providing the first surface-waterbody-level characterisation of PFAS contamination across England, drawing on the Environment Agency 's 2024 national dataset. Linking PFAS detections with sectoral pressure classifications, the study makes the following contributions: 1) quantifies the associations between individual compounds and human activities, 2) assesses WWTWs as pathways for PFAS release, and 3) maps detected PFAS to sector-specific product applications. Our analysis reveals that 92% of monitored waterbodies contain at least one of thirty-four detected PFAS, with multiple compounds co-occurring (mean ∼ 6.5) and PFOS frequently exceeding its Environmental Quality Standard. Water Industry/Domestic/General Public pressures showed strong positive associations with 11 PFAS compounds, with effect sizes of 2.9–9.9 (FDR < 0.05). After adjusting for overlapping sectoral influences, significant positive associations remained for PFHxS.L, PFBS, PFHpA, PFOS..B, PFOS..L and PFOS_combined, with odds ratios between 2.0 and 3.0 (FDR < 0.05). PFAS were also routinely present in WWTWs effluents, where removal efficiencies were often low or negative, indicating that WWTWs function as chronic point sources. Persistent PFOS detections in WWTWs effluents long after its restriction reflect that PFAS are now deeply embedded within the built environment, recirculating through the urban water cycle. These findings underscore the necessity for a comprehensive, system-level governance approach for PFAS that transcends single-compound restrictions and advocates for a fair allocation of mitigation responsibilities.