Microplastics in the Eastern Arabian Sea: Decision support tools for monitoring and environmental risk reduction

The study of microplastics (MP) in the Eastern Arabian Sea (EAS) offers globally relevant insights into the pressing issue of marine plastic pollution. Quantification results (mean concentration of 0.13 particles m^-3 and range of 0.02-0.71 particles m^-3) from the various sectors suggest that terrestrial activities are an important source of MP. By quantifying MP concentrations, identifying predominant polymers, and employing hydrodynamic and particle tracking models, the study provides model simulations that aid in tracking the fate and distribution of MP in coastal environments. Various indices developed in the study suggest significant land-based activity (LBA), low microplastic pollution impact (MPI), and waste management demand (WMD) at medium levels, wherein these indices are replicable and can be applied globally. The development of an Environmental Decision Support System (EDSS) by combining the above indices demonstrates the practical utility of our research in guiding policymakers. This tool can be adapted by governments and organisations worldwide to implement integrated coastal zone management (ICZM), emphasising key strategies like plastic source reduction, regulatory enforcement, and waste management. This study aligns with international goals, including the United Nations' Sustainable Development Goals (SDG 14) addressing plastic pollution from both land-based and marine sources. EDSS identifies regions of high-priority areas for intervention, showcasing that regional data can be scaled up to address global challenges. This research presents a blueprint for managing marine plastic pollution on a global scale, emphasising the importance of integrating scientific findings with innovative policy tools. It underscores the need for a coordinated, region-specific, and globally replicable approach to protect marine ecosystems and ensure sustainable coastal management practices.