Coastal and Marine Pollution in Bangladesh: Pathways, Hotspots and Adaptation Strategies

Marine and coastal pollution is a global issue for human health and biodiversity. We have investigated pollution sources, flow patterns, hotspots, challenges, and adaptation policies in Bangladesh. Industries, ship breaking yards, sewage, tourism, and transboundary depositions are the main sources of pollutions. The Ganges, Padma, Jamuna, Brahmaputra and Meghna carry wastes to the Bay of Bengal. Pollution hotspots are Dhaka, Gazipur, Narshingdi, Narayanganj, Chittagong, Khulna, Mongla port and Sylhet city. Textile and dyeing industries discharge 12.7–13.5 million m3 waste waters annually and pollute 20% of fresh water. Ship breaking yards dump about 22.5 tons polychlorinated biphenyls in a year. More than 50% of the marine oil pollution comes from urban activities. Plastic wastes at 3000 t day-1 and tourism are also contributing to the coastal pollution. Effluent releasing standards are not maintained, and thus higher concentrations of heavy metals are found with marine fishes. Use of heavy metal tolerant crops (rice: BRRI dhan47, potato: Cardinal, mustard: Brassica napus, flower: Marigold, vegetables: Cucumber, fibre: Kenaf, and so on), trap cropping, deep placement of fertilizers, integrated rice-fish-duck culture, etc can be adopted in polluted areas. There are laws for environmental issues, but coordination and financial capabilities does not warrant its effectiveness. Necessary steps are to be taken to improve infrastructure to ensure sanitation and benign discharge of industrial effluents. Systematic study on sources, fate and extent of current effluents dumping in water ways need to be assessed for wellbeing of aquatic life and human health.