Marine pollution is no longer a distant concern, it is a pressing global crisis with real consequences for ecosystems, human health, and coastal livelihoods. According to the United Nations Convention on the Law of the Sea (1994), "pollution" refers to the introduction by humans of substances or energy into the marine environment, including estuaries, that cause harmful effects. Such pollution not only degrades seawater quality and diminishes marine resources but also disrupts the lawful uses of the sea and the facilities that depend on it.
Nowhere are these challenges more visible than in the Bay of Bengal. Located in the northeastern part of the Indian Ocean, the bay has become a frontline of the marine pollution crisis. Its dense coastal populations, heavy maritime traffic, and rich ecosystems make it highly susceptible to the consequences of human-induced pollution. For Bangladesh, whose southern shoreline stretches along the bay, this vulnerability carries profound significance. The country commands jurisdiction over 118,813 km² of maritime territory, including 12 nautical miles of territorial sea and a 200 nautical mile Exclusive Economic Zone. This vast expanse of water is not only a strategic asset but also a cornerstone of Bangladesh's environmental sustainability, food security, and economic resilience making the health of the Bay of Bengal inseparable from the nation's future.
Yet that future is increasingly under threat. Marine pollution is not just altering the color of the Bay`s water, it is reshaping the very balance of life in the Bay of Bengal. The damage to its biodiversity and fragile ecosystems is both visible and silent. A complex mix of pollutants from sea and land-based activities continue to pour into the bay. Oil spills spread across its surface, heavy and trace metals seep into marine organisms, hazardous chemicals linger in sediments, and untreated sewage introduces harmful pathogens. Plastic debris floats endlessly, while excessive nutrients fuel algal blooms that suffocate aquatic life.
What makes the crisis even more alarming is that much of this pollution begins far from the coastline. Industrial discharge including waste from shipbreaking yards, chemical-laden, agricultural runoff, and untreated municipal refuse contaminate inland waters before eventually reaching the sea. Through rivers, outfall systems, and surface runoff, pollutants flow downstream and concentrate in the Bay of Bengal.
Although ships account for roughly 33% of global marine pollution, the greater share over 80% worldwide originates from land-based sources. In Bangladesh, shipbreaking operations along the coast illustrate this stark reality. The dismantling of old vessels releases hazardous substances such as asbestos, polychlorinated biphenyls (PCBs), ozone-depleting substances (ODS), persistent organic pollutants (POPs), and others into the Bay of Bengal, into the surrounding environment. While many of these materials are managed to be carried off the yards as recyclable equipment and supplies, most of them are disposed directly into the ocean. Many old ships also contain extremely flammable compounds that sometimes catch fire in a hazardous environment for shipbreaking and recycling.
Municipal waste further intensifies the problem. Household refuse, industrial and commercial waste, industrial, economic, agricultural, road cleaning debris, construction debris, and sanitary residual often go untreated. In many coastal cities and residential areas of Bangladesh, adequate waste treatment facilities are lacking. As a result, untreated pollutants flow directly or indirectly into the rivers and, finally, into the Bay of Bengal. Industrial activities add to the toxic burden, releasing heavy metals, acids, phenol, ammonia, plastic, alkali, and pharmaceutical wastes into waterways that empty into the sea.
Among these threats, plastic pollution stands out as one of the most pervasive and destructive. The oceans have become gigantic garbage dumps for all types of plastics. Each year, an estimated 8 million tons of plastic enter the marine environment, damaging and often killing marine life. Of this, approximately 2 million tons of plastic reach the Bay of Bengal annually from Bangladesh alone. Plastic is only part of the problem. A wide range of industries, including chemicals, fertilizers, pulp & paper, pharmaceuticals, metal, textile, petroleum, lubricant, and food processing factories, release heavy metals into the ocean waters and pollute marine organisms. Pollution from mining, industrial, and agricultural activities contaminates aquatic environments, rendering waters unsuitable for sustaining biodiversity or supporting coastal development. Heavy metal contamination is particularly dangerous because of its persistence and ability to accumulate in living organisms. It can reduce species abundance by impairing reproduction increasing disease incidence, and eliminating vulnerable native species, thereby weakening entire ecosystems. Marine organisms and fish can accumulate metals in a million-fold higher concentration than the surrounding environment, posing serious risks to human health through seafood consumption.
In both marine and freshwater ecosystems, plastic litter can have a significant environmental and economic impact. Marine animals often suffer from entanglement in plastic debris, ingestion of toxic particles, poisoning, internal injuries, and gradual physical decline-frequently leading to death. The risks extend beyond wildlife. WHO has warned that contaminated water or seafood, including fish, shrimp, and oysters, can contain high concentrations of heavy metals, including mercury, lead, and cadmium. These substances can cause cancer, damage to the central nervous system, and kidney problems. In this way, marine pollution moves from the ocean to our dinner plates.
Oil pollution presents another grave threat. Spills during drilling, processing, or transportation whether by land, pipeline, or ship, introduce toxic petroleum compounds into marine environments.. When these organisms inhale or swallow petroleum products containing toxic compounds, 426 Microbes for Health and Sustainability have detrimental effects on their respiratory, digestive, and cardiovascular systems. Seabirds are especially vulnerable. Oil slicks coat their feathers, reducing insulation and buoyancy, slowing their movement, and making it difficult to find food or escape predators. Many oil-related deaths go unreported, meaning the true scale of the damage is likely far greater than official figures suggest.
Prevention begins with awareness. Government and Non-Governmental Organizations (NGOs) must take the lead in educating the general public in the coastal and river basin region, not through the waste in the ocean and the river. Because all types of pollution are human-made. The environment cannot pollute itself. Awareness campaigns through television, radio, and print media, along with seminars and community workshops, can help people understand the consequences of their actions and encourage responsible behavior. At the same time, enforcement is essential. Authorities should monitor waterways daily, and anyone caught polluting rivers or oceans should face strict penalties. Special attention must be paid to oil dumping vessels, which pose a serious threat to marine ecosystems and must be prevented. By combining education, accountability, and action, we can stop marine pollution and work toward a cleaner, healthier, and more beautiful world for future generations.
Md Mahmudul Hasan is a Researcher & Writer and Urmi Jahan Tanni is Research Manager at Ovibashi Karmi Unnayan Program (OKUP)
