Biodegradation of per- and polyfluoroalkyl substances: mechanisms, challenges, and emerging strategies for sustainable remediation

Abstract

Per- and polyfluoroalkyl substances (PFAS) are highly persistent synthetic chemicals that pose serious environmental and public health risks due to their resistance to degradation, bioaccumulative nature, and toxicity. Their widespread occurrence in water, soil, and biota underscores the urgent need for effective remediation strategies. Conventional methods such as adsorption, filtration, and chemical oxidation, often fail to achieve complete mineralization and may generate harmful by-products. Biodegradation, driven by microbial and enzymatic processes, has emerged as a promising sustainable alternative. This review evaluates recent advances in PFAS biodegradation, focusing on the role of bacteria, fungi, and enzymatic mechanisms, as well as the influence of environmental factors on degradation efficiency. Innovative strategies including enzyme immobilization, phytoremediation, hybrid chemical–biological systems, and machine learning-based predictive modeling are evaluated for their potential to enhance treatment efficiency. Remaining challenges include incomplete understanding of metabolic pathways and limited scalability. A future research roadmap is proposed to integrate metabolic engineering, system optimization, and field-scale validation toward effective, sustainable PFAS biodegradation. This review provides a comprehensive synthesis of current knowledge and outlines strategic directions to advance PFAS biodegradation research and its practical implementation.