Marine Microplastic Pollution and Biodegradation: Current Progress and Future Recommendations

Abstract

: Marine microplastic pollution is a pervasive environmental concern due to its persistence, long-range transport, and ecological and human health risks. This paper focuses on biodegradation as a sustainable strategy to mitigate microplastic impacts. Key findings show that microplastics originate from terrestrial and marine sources, including urban runoff, wastewater effluents, fishing and aquaculture, and are widely transported from surface waters to deep-sea sediments. They threaten marine organisms through ingestion, oxidative stress, reproductive toxicity, and disruption of microbial communities, while humans are exposed through seafood, water, and air. Biodegradation by bacteria, fungi and algae, as well as enzymatic approaches such as PET hydrolases and engineered variants, enable polymer depolymerization, biofilm-mediated assimilation and mineralization. Despite progress, in situ degradation is slow, and the combined effects with other pollutants remain poorly understood. Future research should integrate advanced monitoring, field studies and laboratory experiments, alongside the development of bio-based, biodegradable plastics. Overall, microbial and enzymatic biodegradation offer a promising, environmentally compatible approach for controlling marine microplastic pollution and supporting sustainable plastic management.