Shell has been accused of making false claims about its clean-up operations in Nigeria in a joint report by Amnesty International and the Centre for Environment, Human Rights and Development.
The findings claimed the oil giant had also failed to implement UN recommendations.
The report also alleged several sites Shell had claimed to have cleaned up remained polluted.
However the oil major has said it disagrees with the findings in the report.
Mark Dummett, Business and Human Rights researcher at Amnesty, said: “By inadequately cleaning up the pollution from its pipelines and wells, Shell is leaving thousands of women, men and
children exposed to contaminated land, water and air, in some cases for years or even decades.”
The Amnesty report says four oil spills identified as highly polluted four years ago still remained “visibly contaminated”.
While Shell has accepted spills in the region could have occurred through the failure of pipelines it says pollution is also caused by oil theft and illegal refining.
The spills happened in the Ogoniland region of Southern Nigeria where Shell stopped drilling in 1993 as a result of growing unrest.
Earlier this year the company agreed to pay $84million in a settlement with residents of the Bodo community.
The report also accuses the Nigerian government of failing to properly regulate the oil industry.
Shell says it rejects the findings and says it is “committed to cleaning up all spills”.
It says a thorough clean-up of Ogoniland will take many years to achieve.
