Abstract
Per- and polyfluoroalkyl substances (PFAS) are widespread in environmental media. Concentrations are currently increasing due to substantial ongoing emissions. One approach to mitigating environmental PFAS exposure is the remediation of existing stocks, contaminated sites, landfills, and drinking water. However, the costs to achieve this on a regional scale and amounts of PFAS that could be addressed through remediation remain uncharacterized. To address this, costs for "legacy" and "emerging" PFAS remediation scenarios in Europe were developed based on publicly available site data, remediation cost data, and an expert assessment of currently scalable technologies, through collaboration within a cross-border, collaborative investigation network entitled the "Forever Lobbying Project". The "legacy" scenario reflects remediation to remove previously emitted, long-chain PFAS that are currently widely regulated in Europe from selected hotspot sites and drinking water. The "emerging" scenario targets nearly all PFAS, including ultra-short chain PFAS, across a wider range of intermediate receptors, including wastewater effluent and biosolids. Legacy remediation costs across all 27 EU countries were estimated to be approximately €37 billion over 20 years (€1.8 billion per year), which would lead to a reduction in health impacts. Emerging costs that address shorter chain PFAS in more media were estimated to be about 20 times more expensive at €100 billion per year. However, even this level of investment may be insufficient. This emerging scenario treating 1636 heavily contaminated European soil sites plus all large wastewater plant effluents, large drinking water zones, agriculturally applied sludges, and collected landfill leachate would only address 3 ton per year to 50 tons per year of PFAAs and precursors, which is less than 2% of current estimated EU emissions. The substantial difference in costs between scenarios and the low proportion of emissions that can be addressed with remediation highlight the urgency of implementing use restrictions and source control for PFAS. Preventing PFAS pollution would be less costly and more impactful than relying on remediation after release.