Oil spills are one of the more widely televised forms of marine pollution. Oil spills are defined as the release of oil into any type of waterway, says USA.gov. These spills cause instant harm to marine wildlife and the ocean. However, only 10 to 15 percent of marine oil pollution actually come from oil spills. Natural seepage from sea beds, runoff containing oil and exhaust from cars and motor boats also cause marine oil pollution, according to Global Marine Oil Pollution Information Gateway.
The World Wildlife Fund says that most marine life forms have some degree of chemical contamination. Some of these chemicals include pesticides, radioactive materials and chemicals from manufacturing and consumer products dumped into the ocean. According to the World Wildlife Fund, toxic materials are particularly damaging because small organisms, such as plankton, absorb the chemicals and larger fish and marine mammals digest these organisms. The contamination moves up the food chain and eventually comes back to humans who eat tainted seafood.
Plastic, broken fishing nets, balloons and general household garbage make up a floating array of items harmful to the ocean's health, says OceanLink. Marine mammals end up ingesting garbage or getting their necks caught in fishing nets or plastic rings, resulting in physical harm and potential death from starvation or strangulation. According to Think Beyond Plastic, the biggest example of garbage in the ocean is the Great Pacific Garbage Patch, located in the Pacific between San Francisco and Hawaii, which contains 3.5 million tons of trash.
Anything washed down a drain will eventually make its way to the ocean, says OceanLink. Sewage adds nutrients to the ocean, resulting in massive algae blooms, which lead to oxygen depletion. Without oxygen in the water, marine wildlife cannot survive. In addition, bacteria and parasites from untreated sewage cause disruption to shellfish harvesting and recreational beach use.