toxic waste

The so-called ‘ocean floor disposal’ of radioactive and other toxic industrial waste materials, prevalent in the 1960s and 70s when the ocean was treated by many States as a huge rubbish dump, can still be found today despite regulation prohibiting it.

Dumping was addressed by one of the first international agreements of the IMO, the Convention on the Prevention of Marine Pollution by Dumping of Wastes and Other Matter, adopted in 1972, later updated by the 1996 London Protocol. Under the Protocol, all dumping is prohibited, except for specific wastes (listed as dredged material, sewage sludge, fish wastes, vessels and platforms, inert, inorganic geological material such as mining wastes, organic material of natural origin, bulky items primarily comprising iron, steel and concrete, and carbon dioxide streams from carbon dioxide capture processes for sequestration). Since its entry into force in 2006, dumping has been significantly reduced but not completely eliminated. Further regulation concerning toxins and waste is included in the Basel Convention on the Control of Transboundary Movements of Hazardous Wastes and their Disposal (the Basel Convention), the Stockholm Convention on Persistent Organic Pollutants, the Minamata Convention on Mercury and the International Convention for the Prevention of Pollution from Ships (MARPOL). With all this regulation in place toxic pollution of the ocean has certainly decreased but not eliminated and some still view the ocean disposal as a viable alternative to land disposal. The intention of the Government of Japan to release 1.25 million tons of treated wastewater contaminated by the Fukushima Daiichi Nuclear Power Plant into the Pacific Ocean is one such example. While Japan sees it as the best way to deal with the contaminated water, neighbouring States are concerned that it will affect marine ecosystems in the area.

Other toxic waste dumped into the ocean comes from dredging, industrial waste and sewage. Dredging rivers, canals, ports and waterways contributes about 80% of all waste dumped into the ocean, adding up to several million tons of material dumped each year. According to MarineBio, about 10% of dredged material contains heavy metals such as cadmium, mercury, and chromium, hydrocarbons such as heavy oils, nutrients including phosphorous and nitrogen, and organochlorines from pesticides. When these materials find their way into the ocean, marine organisms suffer toxic effects and seafood is often contaminated. Although many States have established Environmental Protection Agencies to regulate ocean dumping, pollution of the ocean by toxic materials persists.

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BRIEF #28 “The Ocean Is Not a Dumping Ground” Fifty Years of Regulating Ocean Dumping
IISD, December 2021