Review of PFAS Attenuation and Removal in Nature-Based Treatment Systems: Mechanisms, Field-studies, Limitations, and Emerging Challenges

Abstract Purpose This review evaluates the potential and limitations of nature-based solutions (NbS), including constructed wetlands and soil- and aquifer-based systems, for the attenuation of per- and polyfluoroalkyl substances (PFAS) in water. It aims to identify which removal and attenuation mechanisms operate under environmentally relevant conditions and to assess the extent to which NbS can contribute to sustainable PFAS management. Recent Findings Recent field- and pilot-scale studies show that PFAS attenuation in NbS is governed mainly by sorption and physical retention and depends strongly on chain length, functional group, and system conditions. Long-chain PFAS are often partially retained, whereas short-chain, ultrashort, and ether-PFAS remain highly mobile. Biological processes appear to contribute primarily to precursor transformation rather than complete mineralisation and may, in some cases, increase terminal PFAS concentrations. Summary NbS function primarily as attenuation and buffering systems rather than complete PFAS removal technologies. Their effective application will likely require hybrid treatment trains, long-term monitoring, and compound-specific system design. These findings highlight key priorities for future research and implementation. Graphical Abstract