Question: What is the main source of oil pollution in the ocean? Need Assignment Help? Group of answer choices About 99 % of all oil in the ocean is introduced by oil spills such as the tankers Exxon Valdez, Amocco Cadiz, and rigs like the Deepwater Horizon. Almost 85% of the polluting oil in North America comes from river runoff, coastal cities, fuel from small boats and jet skis, and fuel jettisoned by planes. The remaining 15% comes from tanker and pipeline spills and as a result of exploration and extraction from the seabed. About 50 % of oil pollution is from tankers cleaning their ballast tanks on high seas, and the other 50% from oil spills.