Dynamics, ecological implications, and mitigation strategies of the ocean plastisphere

Plastic pollution is a growing global environmental concern that has a significant impact on the marine ecosystem. The resistance of plastics to degradation has led to their accumulation in marine environments, disrupting ecological integrity and biological functions. An estimated 9 million metric tons of plastic enter the ocean annually. The mean abundance of microplastics (MP) in the ocean is estimated to be 2.76 pieces per cubic meter. This review presents an integrated assessment of the sources, pathways, and environmental dynamics of plastic debris, emphasizing its transformation into MP and nanoplastics (NP) through physical, chemical, and biological processes. It examines the interactions between plastic particles and marine organisms, with a focus on their ingestion, trophic transfer, and potential ecological and physiological implications. Particular emphasis is given to the role of plastic surfaces as substrates for microbial colonization, leading to the formation of complex biofilms collectively termed as plastisphere. The review also outlines major global and regional initiatives aimed at mitigating marine plastic pollution, highlighting ongoing policy efforts, technological interventions, and public awareness campaigns. By integrating interdisciplinary research, this review emphasizes the multifaceted nature of plastic pollution, its interactions across biological and ecological scales, and the need for coordinated global strategies to reduce plastic input, enhance waste management practices, and safeguard marine ecosystem health.