TENS of thousands of Amazonians are suing Chevron, the American oil company, for poisoning their waterways in what is billed as one of the biggest environmental cases in history.

The Ecuadorean claimants said the company illegally dumped toxic waste from its oil production, which filtered into the lakes used by thousands of people for washing and drinking.

Celebrity support for the cause ... actress Daryl Hannah in Ecuador’s oil region in the Amazon two years ago. Credit:AP

The result, they claimed, was one of the worst environmental disasters in history, which led to a public health crisis with rising levels of cancer, birth defects and miscarriages.

Some 30,000 Amazonians are behind a case to be heard by an Ecuadorean judge. Experts said the company might have to pay damages of up to $US27 billion ($29 billion).