A United Nations report says there is widespread ecological damage from oil spills in a region of Nigeria's crude-rich southern delta.
The U.N. report, released Thursday, describes oil destroying crops and seeping into drinking water supplies in Ogoniland, a region of the Niger Delta. In one case, the U.N. found one village where drinking water was polluted with benzene 900 times more than the international limit.
The U.N. also found one region where an oil spill 40 years ago hadn't been cleaned.
Some environmentalists say as much as 550 million gallons of oil have poured into the Niger River Delta during 50 years of production _ at a rate roughly comparable to one Exxon Valdez disaster per year.
Nigeria is one of the top crude oil suppliers to the U.S.