Antarctic Sewage Dumping and Global Marine Pollution Threats

The Antarctic is one of the largest pristine environments on Earth. Yet forty-four permanently garrisoned research stations in the Antarctic regularly dump untreated sewage directly into coastal waters off the continent. Microorganisms in that sewage survive for long periods of time in the cold ocean waters and are ingested by fish, marine invertebrates, sea mammals, and birds, posing the threat of disease and death for these animals. The discharge of raw sewage into the oceans in the Antarctic and other parts of the world is only one form of marine pollution. Other marine pollutants include oil spills, heavy metals, toxic chemicals, debris from marine vessels, and radioactive wastes. The release of these materials into the oceans causes disease and death among marine plants and animals, as well as health problems for humans living on land.

The practice of ocean dumping reflects an age-old philosophy that the open seas are a convenient and inexpensive repository in which humans can dispose of their unwanted garbage. Covering nearly three-quarters of the planet’s surface, the oceans have traditionally been seen as a virtually boundless “black hole” into which wastes could be discharged without causing harm to humans or any other living organism. Governments began passing laws to restrict marine pollution only recently. In the United States, for example, the US Congress passed the Rivers and Harbors Act of 1899 in an attempt to reduce the dumping of raw sewage into the nation’s lakes and rivers. It was the first piece of environmental legislation passed in this country. Even then, the concept of marine pollution was essentially unknown until 1967, when the tanker Torrey Canyon accidentally released more than 100,000 tons of crude oil into the ocean 20 miles off the coast of Cornwall, England. For the first time in history, the threat posed by human activities to Earth’s oceans became a topic of worldwide concern.

TOXINS AND THEIR RISKS. Oil spills have long been the best-known example of marine pollution. Accidents like the Torrey Canyon incident have received widespread publicity. But such accidents account for only about 5 percent of all marine oil spills. The remaining 95 percent come from runoff of municipal and industrial oil spills (about 363 million gallons per year), routine maintenance on marine vessels (137 million gallons), air pollutants that dissolve in water (92 million gallons), seepage from natural underwater sources of oil (62 million gallons), and offshore drilling (15 million gallons). Heavy metals, toxic chemicals, and radioactive wastes from industrial operations, agricultural activities, home and garden projects, and trucks, cars, and other vehicles are sometimes dumped intentionally or sometimes washed away accidentally into the oceans. Marine debris includes glass, plastic, metal, and other materials that do not decompose readily and may pose a hazard to plants and animals, including humans. Marine debris may take a staggering variety of forms, ranging from fishing nets and plastic bottles to unexploded bombs and drums of toxic chemicals.

The major risk posed by marine pollution is the toxic character of most pollutants, including petroleum, heavy metals, toxic chemicals, pathogens in sewage, and radioactive materials. These pollutants may kill marine plants and animals directly or may be ingested and then passed on to higher organisms—including humans—by whom they are eaten. Forms of debris that are not toxic can still cause harm to marine organisms. Marine birds and mammals may become entangled in fishing nets or plastic bottle rings, or they may be injured by broken glass or sharp pieces of metal.

A number of national laws and international treaties dealing with marine pollution have been adopted. These laws and treaties include the Convention on Fishing and Conservation of the Living Resources of the Sea (1958), the Brussels Intervention Convention on Oil Spills (1969), the International Convention on Civil Liability for Oil Pollution Damage (1969), the International Convention for the Prevention of Pollution by Ships (1973), the United Nations Convention on the Law of the Sea (1982), and the Convention on the Prevention of Marine Pollution by Dumping of Wastes (1990).

The Dangers of Chemical Weapons Disposal. It is estimated that about 1.4 billion tons of trash enter the oceans every year and that this pollution may be responsible for killing about one million seabirds annually. Chemical weapons disposal, now banned by international treaties, could be the most problematic trash in the world’s oceans. For instance, the US Army is estimated to have dumped about 64 million pounds of nerve and mustard gas agents in the ocean between the Second World War and 1970 (the US Congress banned the practice in 1972). Saltwater corrosion may eventually release some of the harmful chemicals, with a potentially lethal impact on marine life and humans as the main consumers. Rainer F. Buschmann

A host of human activities still threaten the health of the world’s oceans. Huge new cruise ships now produce up to 30,000 gallons of sewage each day, most of which is dumped directly into the oceans. Companies in Indonesia are building new gold mines that will release 3,000 to 4,700 metric tons of waste—containing cyanide, arsenic, and other toxic substances—into offshore waters every day. High concentrations of toxic chemicals in narwhals and belugas (whales that form an important part of the diet of people who live in Arctic regions) threaten not only the survival of the whales but also the lives of humans who eat them. Many efforts have been made to solve the problems of marine pollution, but many more challenges remain.

FURTHER READING: Birkland, Thomas A. 1998. “In the Wake of the Exxon Valdez.” Environment 40: 4-11.

Burger, Joanna. 1997. Oil Spills. Piscataway, NJ: Rutgers University Press.