Detection and degradation of microplastics in the environment: a review

Abstract

Microplastics (MPs) are a growing environmental concern due to their persistence in the environment and potential negative impacts on human health and the ecosystem. Their widespread presence across terrestrial, aquatic, and atmospheric compartments has prompted an urgent need for improved detection techniques and effective degradation strategies. This review provides an integrated overview of recent advancements in the identification and removal of MPs, with a focus on both analytical and remediation technologies. Progress in spectroscopic, thermal, and imaging-based methods has enabled more precise detection, quantification, and characterization of MPs, particularly at the nano-scale. Simultaneously, a variety of degradation strategies have been developed to mitigate the environmental burden of MPs. These are broadly categorized into physical, chemical, and biological approaches. Physical methods include mechanical removal and thermal processes such as pyrolysis and thermal oxidation. Chemical degradation involves advanced oxidation processes (AOPs) and photocatalysis using semiconductors like titanium dioxide (TiO₂) to accelerate polymer breakdown under light exposure. Among biological approaches, enzymatic and microbial degradation have shown promising results. Enzymes such as PETase, MHETase, cutinases, lipases, and cellulases catalyze the hydrolysis of ester and amide bonds in synthetic polymers, offering selective and environmentally benign pathways for microplastic decomposition. The review further explores the implications of microplastic accumulation, including bioaccumulation and oxidative stress in organisms, and discusses the limitations and challenges of current technologies. Emphasis is placed on integrating detection with degradation strategies to achieve sustainable, scalable, and interdisciplinary solutions. By highlighting the latest scientific advancements, this review aims to guide future research directions and support the development of effective policy and management frameworks for mitigating microplastic pollution.