Per-and Polyfluoroalkyl Substances (PFAS): A Global Review of Sources, Contamination, Risks, Analytical Challenges, and Remediation Strategies

Abstract

Per-and polyfluoroalkyl substances (PFAS) are a large class of synthetic fluorinated compounds extensively used in industrial applications and consumer products due to their exceptional chemical stability and resistance to degradation. These same properties, however, contribute to their environmental persistence, leading to global contamination and growing concern over their ecological and human health impacts. This review provides a comprehensive synthesis of current knowledge on PFAS sources, environmental distribution, and transport across water, air, soil, sediments, and biota. It highlights regional disparities in regulatory frameworks and underscores limitations in existing monitoring efforts, including analytical detection challenges and the underrepresentation of emerging PFAS. The toxicological profile of PFAS is examined, with emphasis on bioaccumulation, endocrine disruption, immunotoxicity, and developmental effects. Remediation strategies are critically assessed, including activated carbon adsorption, reverse osmosis, advanced oxidation processes, electrochemical degradation, and in situ stabilization. While progress is being made in reducing exposure and remediation, substantial knowledge gaps remain, particularly regarding methods to characterize and assess the cumulative risk posed by complex mixtures of PFASs. This includes methods to assess the risk posed by PFAS "precursor" compounds, including polyfluoroalkyl substances, that can degrade to "terminal" perfluoroalkyl substances recalcitrant to further degradation. PFAS represent a large and diverse group of fluorinated compounds whose persistence, bioaccumulation, and global distribution have created unique regulatory and remediation challenge. Their chemical diversity and ubiquity call for cross-sector collaboration supported by advanced analytical approaches and adaptive policy frameworks. Therefore, improving PFAS detection and assessment capabilities is essential for developing effective and sustainable remediation strategies. In addition, stronger international collaboration is proposed to address the global nature of PFAS contamination, as addressing the long-term risks posed by PFAS will require an integrated approach grounded in innovation, lifecycle-based regulation, and global coordination.