India’s role in global fight against marine pollution

What is marine pollution?

Marine pollution is defined by the 1982 UN Convention on the Law of the Sea (UNCLOS) as “the introduction by man, directly or indirectly, of substances or energy into the marine environment, which results or is likely to result in such deleterious effects as harm to living resources and marine life.” 

The significance of the issue is well reflected in Sustainable Development Goal 14.1, which calls for the prevention and significant reduction of marine pollution of all kinds, particularly from land-based activities. 

Marine pollution, originating from both land and sea, is a complex and interconnected problem. Land-based pollutants account for approximately 80 per cent of marine pollution, and the rest comes from sea-based sources. Untreated sewage and industrial wastewater carry waste and toxic substances into rivers and then coastal waters. 

Agricultural waste containing residues of nitrogen-based fertilizers migrates to the sea through water bodies, leading to eutrophication – a high level of nutrient concentrations, usually nitrogen and phosphorus. It leads to harmful algal growth and deprives ocean areas of oxygen, creating dead zones in which marine life cannot exist.

In addition to this, plastic waste, including microplastics, is also a major source of marine pollution. This waste generated on land is transported from urban centres and dumping sites through the river system. Ocean currents in some regions concentrate marine debris into vast floating garbage patches, the largest being the Pacific Trash Vortex.

Sea-based marine pollution arises from activities in the seas, with discharge from shipping vessels constituting a major source. Discharge of untreated ballast water from ships carries invasive species and contaminants. Similarly, air and noise pollution degrade the marine environment. Oil spills caused by shipping accidents, offshore drilling, and maritime operations release large quantities of hydrocarbons into the marine environment, causing damage to marine life. In addition, extractive activities, such as mining, disturb the seabed ecosystems. 

Impact on marine ecosystems and human health

Marine pollution poses a serious threat to marine ecosystems and human health. One of the most severe impacts is the loss of marine biodiversity. Plastics, oil spills, toxic chemicals and abandoned fishing gear harm marine species through ingestion, entanglement, and exposure to toxic substances. It is estimated that around 100,000 mammals are killed each year due to plastic, while 81 of 123 marine mammal species are known to have eaten or become entangled in plastic. 

Marine ecosystems function through delicate interdependencies. Pollution disrupts plankton populations (microscopic plant-like organisms), which form the base of the marine food chain and play a crucial role in carbon sequestration. Declining plankton productivity has implications not only for fisheries but also for global climate regulation. 

Also, mangroves and seagrasses, which act as natural buffers against storms and coastal erosion, are affected by oil coating and sediment contamination. Their degradation increases the vulnerability of coastal communities to cyclones and sea-level rise.

Marine pollution also has deleterious effects on human health. More than 3 billion people in the world rely on wild-caught and farmed seafood as a significant source of animal protein. When seafood is contaminated with pollutants like Methylmercury and Polychlorinated Biphenyls – persistent, toxic industrial chemicals that bind to sediments and accumulate in fatty tissues – they increase risks for cardiovascular disease and dementia, and have fatal consequences for unborn or newborns. 

National and international efforts to contain marine pollution 

At the international level, various treaties and conventions have been adopted to regulate, prevent, and control marine pollution and to promote the protection and sustainable use of marine ecosystems. 

The most significant of which is UNCLOS, which is the primary legal framework for the protection and preservation of the marine environment at the global level. It obliges states to prevent, reduce, and control pollution from land-based sources, seabed activities and dumping vessels. 

The Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter 1972 (or the London Convention) came into force in 1975 with the main objective of promoting the effective control of all sources of marine pollution and to take steps to prevent pollution by dumping of wastes in the sea. 

In 1973, the significant International Convention for the Prevention of Pollution from Ships (MARPOL Convention) was adopted. It deals with the prevention of pollution by all substances carried in ships, including oil, chemicals, harmful substances, and ship-generated sewage and garbage. 

To control invasive aquatic species introduced through shipping, the Ballast Water Management Convention was adopted in 2004. It established standards and procedures for the management and control of ships’ ballast water and sediments.

India has also taken various steps to prevent and control pollution from ships. Apart from the general pollution controlling laws, the maritime legislations also enable the government to take steps to control marine pollution. For example, the Merchant Shipping Act, 1958, contains rules on the prevention of pollution of the sea. 

Similarly, the Maritime Zones of India Act, 1976, enables the government to take measures for the protection of the marine environment. In compliance with MARPOL Annex VI, the Directorate General of Shipping issued a circular in 2019 on limiting sulphur content in ship fuel. 

Need for a holistic and participatory ocean governance

Despite such international conventions, national laws, and technological mechanisms, marine pollution has emerged as one of the most pressing environmental challenges. For a country like India, with a coastline of 11,098 km and around 200 million people dependent on the sea for their sustenance and livelihood, ocean health is crucial.  

Since most of the marine pollution comes from land-based activities, it underlines the need for effective implementation of waste management laws and treatment of sewage and industrial effluents. 

As ocean pollution is a transboundary problem, international cooperation is essential. States need to focus on strengthening the enforcement of frameworks, such as UNCLOS and MARPOL, through information sharing and joint monitoring. At the global level, the proposed legally binding treaty on plastic pollution needs to consider a lifecycle approach covering plastic production, consumption and waste management. 

Defence Minister Rajnath Singh termed marine environment protection not just a strategic necessity, but a moral responsibility. Hence, it is crucial to focus on scientific monitoring, public awareness and community participation, especially to promote responsible production and consumption. 

Post read questions

What is marine pollution? How is the Indian Coast Guard Ship (ICGS) ‘Samudra Pratap equipped to deal with it?

Land-based sources account for the majority of marine pollution. Discuss the implications of this for environmental governance and coastal management in India.

Why is marine pollution increasingly becoming a threat to ecological security and coastal livelihoods in India? Evaluate the major sources of marine pollution and the effectiveness of India’s response mechanisms.

Critically examine India’s role in global efforts to combat marine pollution, including the proposed legally binding treaty on plastic pollution.

Despite the existence of international conventions and national laws, marine pollution continues to worsen. Analyse the governance and implementation challenges in tackling marine pollution.

(Renuka is a Doctoral researcher at Himachal Pradesh National Law University, Shimla.)

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