Adsorption-based removal of PFASs from water: mechanisms, materials and future perspective

Environmental context Per- and polyfluoroalkyl substances (PFASs), often called ‘forever chemicals’, have contaminated water sources worldwide and pose serious health risks. This study reviews how adsorption technologies – using materials such as activated carbon and advanced nanomaterials – can effectively capture and remove PFASs from water. These insights support the development of safer, more efficient treatment solutions and guide future policies to protect public health and the environment. Abstract Per- and polyfluoroalkyl substances (PFASs), a large and chemically diverse group of synthetic fluorinated compounds, have been extensively used in industrial processes and consumer products due to their remarkable thermal stability and resistance to degradation. However, their environmental persistence, bioaccumulation potential and associated health risks are of growing global concern, especially given that PFASs have been detected in over 98% of the US population and in ecosystems worldwide, with estimated environmental half-lives spanning decades to centuries. This review critically and comprehensively synthesises current knowledge on PFAS production, environmental dissemination and management strategies. It explores major contamination sources and pathways, highlights their global distribution and examines the evolving regulatory landscape. The review focuses on adsorption-based removal technologies, in-depth evaluating mechanisms of PFAS interactions with adsorbents such as activated carbon, biochar, metal–organic frameworks (MOFs) and ion-exchange resins. A comparative analysis of these materials considers their removal efficiencies, operational constraints and energy demands. Furthermore, the review also identifies challenges and knowledge gaps, including the need for improved mechanistic understanding, standardised testing and long-term performance data. Looking ahead, the article discusses future directions for PFAS remediation, including the development of advanced hybrid adsorbents, the integration of machine learning for material design and the alignment of scientific innovation with policy. The review concludes with recommendations for harmonised regulations and interdisciplinary collaboration to support sustainable and effective PFAS mitigation efforts.