Comprehensive review of per- and polyfluoroalkyl substances in drinking water: Physiochemical properties, sources, health impacts, regulatory limits, and future perspectives

Abstract

Per- and polyfluoroalkyl substances (PFAS) are a large group of synthetic chemicals defined by strong carbon–fluorine bonds, contributing to their exceptional environmental persistence and resistance to degradation. Structurally diverse, PFAS are classified into polymeric and non-polymeric types and are widely used in industrial and consumer products due to their hydrophobicity, lipophobicity, and thermal stability. However, their extensive use has led to global water contamination through industrial discharges, firefighting, landfill leachate, wastewater effluent, and consumer product runoff. Human exposure to PFAS, even at trace levels, is associated with serious health effects, including immune suppression, developmental and neurotoxicity, liver dysfunction, cardiovascular disease, and certain cancers. In wildlife, PFAS cause reproductive harm and biomagnify in food chains. Regulatory bodies worldwide have responded by setting maximum contaminant levels, though thresholds and enforcement vary among regulatory agencies and the countries setting them. While advanced analytical methods like LC-MS/MS enable PFAS detection, limitations in cost, scope, and sensitivity hinder widespread monitoring. Current treatment methods, including granular activated carbon, ion exchange resins, and high-pressure membranes, face challenges in removing short-chain PFAS and scaling to large systems. To address these issues, there is increasing support for regulating PFAS as a single chemical class and applying the “essential use” and “P-sufficient” principles to restrict non-essential applications and prevent regrettable substitutions. Future progress depends on harmonized global regulation, improved analytical tools, and the development of cost-effective, scalable water treatment technologies. This review outlines PFAS classification, sources, health impacts, regulations, detection and removal challenges, highlights future directions for risk management.