An oil spill is the release of a liquid petroleum hydrocarbon into the environment, especially marine areas, due to human activity or natural disasters, and is a form of pollution.

The term is usually applied to marine oil spills, where oil is released into the ocean or coastal waters, but spills may also occur on land.

The Largest Oil Spills in History

Arabian Gulf/Kuwait
When: Jan. 19, 1991
Where: Persian Gulf, Kuwait
Amount spilled: 380-520 million gallons

Gulf oil spill
When: April 22, 2010
Where: Gulf of Mexico
Amount spilled: An estimated 206 million gallons

Ixtoc 1 Oil Spill
When: June 3, 1979
Where: Bay of Campeche off Ciudad del Carmen, Mexico
Amount spilled: 140 million gallons

Atlantic Empress Oil Spill
When: July 19, 1979
Where: Off the coast of Trinidad and Tobago
Amount spilled: 90 million gallons

Kolva River Oil Spill
When: Aug. 6, 1983
Where: Kolva River, Russia
Amount spilled: 84 million gallons

Nowruz Oil Field Spill
When: Feb. 10, 1983
Where: Persian Gulf, Iran
Amount spilled: 80 million gallons

Castillo de Bellver Oil Spill
When: Aug. 6, 1983
Where: Saldanha Bay, South Africa
Amount spilled: 79 million gallons

Amoco Cadiz Oil Spill
When: March 16, 1978
Where: Portsall, France
Amount spilled: 69 million gallons

ABT Summer Oil Spill
When: May 28, 1991
Where: About 700 nautical miles off the coast of Angola
Amount spilled: 51-81 million gallons

M/T Haven Tanker Oil Spill
When: April 11, 1991
Where: Genoa, Italy
Amount spilled: 45 million gallons

Odyssey Oil Spill
When: Nov. 10, 1988
Where: Off the coast of Nova Scotia, Canada
Amount spilled: 40.7 million gallons

The Sea Star Oil Spill
When: Dec. 19, 1972
Where: Gulf of Oman
Amount spilled: 35.3 million gallons

The Torrey Canyon Oil Spill
When: March 18, 1967
Where: Scilly Isles, UK
Amount spilled: 25-36 million gallons