British lawyers have mounted the largest class action yet lodged in the UK courts for up to 30,000 Africans allegedly poisoned by toxic waste dumped by an oil tanker.

The action is being brought against Trafigura, a London-based multinational, over the dumping in 2006 of 400 tonnes of toxic waste in the Ivory Coast. The waste, containing high levels of caustic soda, a sulphur compound and hydrogen sulphide, gave off toxic fumes and allegedly led to 100,000 people going to clinics suffering from vomiting, diarrhoea and breathing difficulties after exposure to the waste. Ten people died.

The company was accused of dumping the poisonous black sludge, or slops, that arose from removing impurities including sulphur from the raw oil, in rubbish tips, drains, abattoirs and lagoons in Abidjan, the commercial capital of the Ivory Coast, in August 2006.

The Ivory Coast Government was forced to resign and the United Nations paid £30 million to help with the medical costs of setting up free clinics and cleaning up.

Now a team of 15 British lawyers has lodged claims for 17,000 people and has just returned from the Ivory Coast with a fresh tranche of 3,000 claims. At a recent hearing in the High Court in London the lawyers predicted that the total would reach 30,000 by trial. The trial is expected to take place between April and July next year.

Martyn Day, senior partner with Leigh Day & Co, which is funding the group action from its own funds on a “no win, no fee” basis, said it was right that a multinational was held to account in the British courts. “That we can bring a case with 30,000 claimants from a far-off land to trial within three years of the events shows that in England we have a system for group claims that is second-to-none in the world in holding multinationals to account for their actions,” he said.

The law firm was brought in by Greenpeace, which in turn was asked to help by the Ivorean Government. Until 2006 Day was chairman of Greenpeace UK and is still on the executive of the Greenpeace Trust. “We would not be bringing the claims under the ‘no win, no fee’ scheme if we did not think that they had a strong chance of winning,” he said. “The strength of our system is that by allowing us to charge a success fee in the claims we win, we can develop a treasure chest to help to finance large cases like this.”

Legal proceedings began in November 2006 and the court granted an order for the group litigation to proceed in February last year. That same month it emerged that the company had agreed to pay £100 million to the Ivory Coast for the environmental damage caused, in one of the largest settlements of its kind. The money was to enable the State to clean the sites and to make payments to individuals claiming to have been affected by the dumping. The company has made no admission of liability.

The pollution came about after a Trafigura-chartered tanker failed to agree a price to dispose of the waste with the Dutch Government. An Ivory Coast company was awarded the waste disposal contract instead. The director of Trafigura, Claude Dauphin, and two other executives of the trading group found themselves arrested and held in prison in Abidjan when in September 2006 they flew to the country to investigate the pollution. They were released later.

Simon Nurney, a partner with Macfarlanes, who is acting for Trafigura, said: “Not only does Trafigura not accept that it was liable for the events, it also does not consider that the slops dumped by the local company could have caused anything like the symptoms alleged by the claimants in the English court proceedings.

“Trafigura sought reputable local advice in 2006 as to which companies were able to undertake the deslopping operation. It relied on that local advice, together with the fact that the company eventually selected was readily able to provide governmental licences and port approvals for undertaking this type of activity.” Trafigura exercised “far more care” in assessing the local company than usually undertaken by shipowners or charterers for a deslopping operation.

In no way, he added, did the investigation support “the presumption that the slops did, in fact, cause the injuries alleged”. The company paid the £100 million to the Government of the Ivory Coast, he said, “because as a major trading company in West Africa for a number of years, Trafigura believes it has an economic responsibility to the region. It also has considerable sympathy for the people of Abidjan and is working to improve their lives.”

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