Microplastics pollution load in Sundarban delta of Bay of Bengal

Microplastics have been reported in sediments, surface water, and aquatic organisms, including seafood, and thus transferred to food chains. This paper summarizes the emerging concern of microplastic pollution and highlights mitigation policies and action plans in the Sundarban Delta regions in Bay of Bengal. Sundarban is the largest mangrove forest with vibrant and rich biodiversity, facing severe threats because of human activities and climate change. Anthropogenic plastic litter has been found in the Bay of Bengal and thus also in Sundarban, which can cause substantial threats to mangrove forests. More than 56 tons of plastic wastes were found in the Sundarban immediately after the cyclone ‘Amphan’ in 2020 due to unregulated relief packaged materials using plastics. Interestingly, microplastics have also been found in the Bay of Bengal and Sundarban, ultimately transported from various rivers and waved off to the Sundarban mangrove. It has been observed that 4 million tonnes of microplastics have been discharged annually from various rivers of India and Bangladesh to Sundarban and the Bay of Bengal. Trophic transfer of microplastics and their bioaccumulation can result in significant ecological damage to the Sundarban delta. Although the governments of India and Bangladesh have been taking different policy measures for protecting the mangrove forest areas, more policy interventions are required to tackle emerging contaminants like microplastics. Other issues may also arise from huge load of microplastics, such as degradation of natural resources, unsustainable livelihoods, and poverty. In this regard, joint initiatives of both countries are required to consider pollution risk assessments, biodiversity conservation, and sustainable development.