Tens of thousands of Ecuadoreans living in the Amazon rainforest are suing Chevron, the US oil company, for poisoning their waterways in what is billed as one of the biggest environmental lawsuits in history.
The claimants say the company illegally dumped toxic waste from its oil production which filtered into the waterways and lakes used by thousands of people for washing, drinking and cooking.
The result, they say, was an environmental disaster worse than the 1989 Exxon Valdez oil spill, which in turn has provoked a public health crisis, with soaring levels of cancer, birth defects and miscarriages.
Some 30,000 Amazonians are behind a lawsuit to be heard by an Ecuadorian judge. Experts say the company might have to pay up to $27bn (£16bn) in damages.
The company insists there is no proof that any illnesses were caused by its operations, and says the responsibility for cleaning the area lies with the Ecuadorian government and Petroecuador, the state oil firm.
Chevron says the court case is the result of the exploitation of the indigenous population by US trial lawyers in connivance with a corrupt government.
But the Amazon campaign has attracted some high profile supporters, including Trudie Styler, the wife of musician Sting, and human rights campaigner Kerry Kennedy, a member of the US dynasty. Chevron's reputation for corporate social responsibility has already taken a blow.
The issue is also the subject of Crude, a recent and critically-acclaimed documentary by Joe Berlinger. The rags-to-riches tale of the chief Ecuadorian lawyer fighting the case has also earned it a place on the front cover of Vanity Fair.
Texaco, which is owned by Chevron, first started operating in Sucumbíos, in northeastern Ecuador in 1964 and in 26 years made $490m (£294m) and produced 1.7 billion barrels of oil.
As the operator of a consortium with Petroecuador, it drilled hundreds of wells in an area of 1,500 square miles and for each one, a series of pits in which to put the water produced as a byproduct of the oil.
Those fighting Chevron claim the 18 billion gallons of water put into the pits was toxic and was allowed to overflow into nearby rivers. They also claim Texaco spilled an additional 17 million gallons of crude oil.
The resulting contamination has increased cancer rates in the area threefold, they claim, and led directly to the deaths of 1,400 people.
"Texaco treated Ecuador's Amazon like a garbage dump," said Douglas Beltman, a former official at the US Environmental Protection Agency who serves as a scientific consultant to the affected indigenous groups. "Almost everything an oil company could do wrong, Texaco did do wrong."
One of the families allegedly affected is that of five-year-old Yahaira Sanchez. Yahaira's grandmother died of cancer and her parents are terrified the girl could fall ill too, but they are forced by lack of options into using the local water.
Yahaira's father William, who farms his own smallholding, said: "We want to move to protect Yahaira's health but we are too poor."
Another local man, known only as Roberto, told Penny Marshall, an ITN correspondent who investigated the issue, that his son had died of leukemia and his wife was suffering from cancer. Asked why, he said: "I think it's the contamination."
Kent Robertson, a spokesman for Chevron, said there was no evidence that any death or illness had been caused by its operations. He said that when Texaco left Ecuador in the early 1990s, it arranged for 40 per cent of the pits to be decontaminated and signed a contract with the Ecuadorian government that Petroecuador would deal with the rest. Any sign of contamination now was Petroecuador's work, he said.
Asked whether the firm had fulfilled its moral obligations to the Ecuadorians, he said: "We are in the business of producing energy for the future, not the cleaning up after other companies or making trial lawyers rich."
Despite this, he said, the Ecuadorian judge hearing the case in Lago Agrio, the provincial capital, was likely to rule against Chevron later this year.
"If the case is based on the legitimate evidence which has been produced, Texaco will be exonerated," he said. "The concern on our part is that the evidence doesn't matter and the government of Ecuador has already determined what the outcome is going to be. The trial is largely a formality."