A three-year investigation by the United Nations will almost entirely exonerate Royal Dutch Shell for 40 years of oil pollution in the Niger delta...The $10m (£6.5m) investigation by the UN environment programme (UNEP), paid for by Shell, will say that only 10% of oil pollution in Ogoniland has been caused by equipment failures and company negligence, and concludes that the rest has come from local people illegally stealing oil and sabotaging company pipelines...[T]he investigation was accused of bias by Nigerians and environmental groups who said the study...was unbalanced...[Mike Cowing, head of UN research team] denied the UN was being influenced by Shell or the government...The full report, due to be published by December, is expected to warn of an environmental catastrophe..."This is not directly comparable to the spills that occurred in the Gulf [of Mexico]," said Cowing. "But we have a serious and profound problem."