Last month the commodities trader Trafigura settled with plaintiffs in a lawsuit brought by the British law firm Leigh Day & Co, agreeing to pay millions in damages. The firm represents some 31,000 plaintiffs in Ivory Coast, where 15 people are said to have died and thousands more were poisoned by the toxic waste dumped there in 2006 by the Trafigura-owned ship Probo Koala.

A similar deal was reached with the Ivory Coast authorities in February 2007 for 152 million euros. In both cases Trafigura made clear that the settlement was not an admission of guilt. Greenpeace, for one, refused to leave it at that, and is now trying to establish Trafigura's guilt in a separate court case in the Netherlands.

A disaster unfolds

There is hardly a newspaper in the world that hasn't described the horrors of the toxic disaster in Ivory Coast in harrowing words, usually illustrated by gruesome pictures of Ivorians covered in boils or other skin infections. Or of pools of disgusting thick, tar-like sludge, danger signs with skull symbols and men in white protective suits and gas masks.

Far less attention was given to a statement that was part of last month's settlement between Trafigura and Leigh Day.

On September 19, 20 experts who investigated the events in Abidjan came to the conclusion they had been unable to establish a link between the dumping of refinery waste ('slops') and the deaths, miscarriages, birth defects and other health problems that have been reported in the media. "Leigh Day and Co, in the light of the expert evidence, now acknowledge that the slops could at worst have caused a range of short term low level flu like symptoms and anxiety," the 'agreed final joint statement' says.

Martyn Day of Leigh Day & Co refused to comment for this article. "Under the terms of the agreement with Trafigura we are unable to comment further", he said. Wrong, Trafigura said in an email, it was specifically agreed upon that all parties were free to respond to questions from the media.

The Dutch connection The Netherlands has a special connection to the Probo Koala incident. Not just because Trafigura Management's headquarters are officially located in Amstelveen, but also because the Probo Koala spent time in the Amsterdam port in July 2006, just before heading to Ivory Coast. Trafigura had initially asked a company called APS (now MAIN) to process the refinery waste or 'slops'. APS started the work, but the stench released in the process was so overpowering that neighbours called the fire department. APS also found that the slops were far more polluted than Trafigura had led them to believe. The significance of the waste's transit through Amsterdam is that the Dutch authorities, following the calls to the fire department, took several samples from APS and the Probo Koala, which were later analysed by the national forensic institute (NFI). The NFI found no scary substances in the waste; it consisted mostly of a concentrated mix of NaOH (natrium hydroxide) in water, which apart from phenols also contained hydrogen sulfide (H2S) and mercaptans. The same distasteful waste is generated daily in oil refineries, and is usually disposed of on the factory grounds. If wrongly treated there is a risk that the dangerous H2s and mercapatans are released. After some haggling betwen Trafigura and APS – the Amsterdam company wanted to raise the price 20-fold – the Probo Koala took the slops back and set out to sea. On August 19, 2006 it arrived in Ivory Coast, where the slops were taken off the ship by a local company, Société Tommy, and dumped at sites all over Abidjan. Tommy's owner and a port worker who recommended the firm to the crew of the Probo Koala were sentenced to twenty and five years in prison last year.

The obvious question to Leigh Day & Co would have been: did its own experts - each party had 10 - also agree to the joint statement? The answer, which had to come from Trafigura, was: yes, they did.

Two weeks before the settlement UN special rapporteur Okechukwu Ibeanu issued his own report about the Probo Koala incident. It said there seemed to be "strong prima facie evidence that the reported deaths and adverse health consequences are related to the dumping of the waste". But Ibeanu also admitted "there is still some contention among scientists as to the actual causality".

Good riddance

The waste aboard the Panama-registered Probo Koala originated in Mexico. After a brief passage through the port of Amsterdam (see insert), the Probo Koala arrived in Ivory Coast on August 19, 2006, where a company called Société Tommy offered to take the slops off Trafigura's hands.

Tommy's drivers transfered the waste to chartered tanker-trucks and dumped it at various waste dumps in and around Abidjan, in the sewer system and even directly in the local lagune. Altogether there were some 16 dumping sites, some of them very minor. What Tommy's drivers didn't do was neutralise the waste: they dumped it exactly the way it left Amsterdam, highly alkaline (a high concentration of pH).

Shortly after the waste was dumped people in Abidjan reported an unbearable stench. First reports mentioned a smell of garlic and cooking gas. The stench probably came from mercaptans which are also added to natural gas to make it detectable. People in Abidjan, one of the most polluted cities in the world, are used to bad smells, but this one caused irritation and concern.

Within a few days the popular anger had been hyped by the local media to the point where the authorities felt compelled to react. On August 24 victims were advised to report to a hospital. Some local media speculated about radio-activity and carcinogens. The hospitals were swamped, resulting in chaos. Thousands of people were sent home with every kind of medicine in stock until the hospitals ran out of even the last paracetamol and otrivin. The government resigned and then un-resigned. By that time everyone in Abidjan was convinced they had been poisoned.

On September 5, AFP correspondent David Youant quoted a hospital director as saying two girls had died from the poisoning. The next day president Laurent Gbagbo addressed his people. On September 8, Achim Steiner, executive director of the UN environmental organisation UNEP, said "the disaster in Abidjan is a particularly painful illustration of the human suffering caused by the illegal dumping of wastes".

'False sense of poisoning'

On that same day a team of six French firefighters and disaster experts arrived in Abidjan and started testing. Even close to the dumping sites they were unable to detect dangerous concentrations of hydrogen sulfide (H2S) and mercaptans. They concluded the danger had passed.

A team of experts from the UN's disaster agency UNDAC who arrived a few days later concurred with the French. UNDAC estimated that there was no longer any danger three weeks after the waste was dumped, but that the stench from the remaining mercapants created a 'false sense of poisoning'. UNDAC also noted that sensational media reports had contributed to a climate of fear, not just among the local population, but also among UN organisations based in Ivory Coast.

On September 13 an official from the Ivorian health ministry suggested they might be dealing with a collective psychosis. The danger of breathing in toxic gases had now completely disappeared, he said.

And yet the number of victims kept rising, as did the official death toll, which would be raised to 15 on February 17, 2007, when the waste from the Probo Koala had long been removed by the French waste removal company Tredi and disposed of in France.

What's official?

The problem is the word 'official' in 'official death toll' has little meaning in the context of Ivory Coast. Whoever has witnessed the chaotic response of the Ivory Coast authorities, the conditions at the hospitals, and the important-sounding but clumsy reports issued by the Ivorians can only come to the one conclusion: they will say whatever.

Any government that calls for victims to register themselves for future compensation knows full well they're going to get a lot of people coming forward. The web site www.asso-sherpa.org has a list of 100,000 victims, complete with names, ages and addresses, mostly from the Cocody neighbourhood, which given the prevailing southeasterly winds in August and September would hardly have been exposed to the stench.

All of this leads to one conclusion: it has never been established beyond doubt that the waste from the Probo Koala has made any victims at all. Experts have not been able to make an 'exposure assessment'. That in itself is not uncommon. Scientists have other means at their disposal, such as a reconstruction of the exposure based on exposure models, plausible source strength and meteorological data. Surprisingly there has been almost no scientific interest in the Abidjan 'disaster': the medical database PubMed contains only one insignificant article from Médecine tropicale (December 2007).

The chickens are fine

Ironically, the strongest indication so far that the dumping of the slops from the Probo Koala, however reprehensible, was not as disastrous as previously suggested, is unwittingly provided by Greenpeace itself.

On its website, Greenpeace mentions a survey done by young Ivorian collaborators of the Centre Suisse de Recherches Scientifiques en Côte d’Ivoire in October 2006. They went door to door, looking for complaints, which of course they found, but never further than 3 kilometres from a dumping site. Given the extreme stench from mercaptans this seems to suggest that the concentrations were never very high even in relatively close proximity to the dumping sites.

More importantly, the researchers found healthy chickens and pigs as close as 100 metres from the dumping sites. The report is indignant about their presence, because the authorities at the time ordered all animals to be slaughtered, which a lot of Ivorians apparently didn't do. The researches failed to see the importance of the fact that the chickens and pigs in question were apparently unaffected by the waste from the Probo Koala. The chickens and pigs hadn't read the newspapers, listened to the radio or been exposed to Greenpeace.

Finally, there is the fact that the French company Tredi removed almost 20 times more waste from Ivory Coast than the Probo Koala dumped there. This is because the refinery waste was dumped at existing garbage dumps. The black drab and rusty oil drums that were a fixture in news reports about the 'disaster' were already there long before the Probo Koala called in Abidjan.

Trafigura caves to Guardian and British parliament After trying to impose a gag order on both the Guardian and the British parliament, Trafigura on Friday released a 2006 report about the Ivory Coast waste dumping. Trafigura's lawyers obtained a so-called super-injunction against the Guardian to keep the newspaper from writing about a question by a British member parliament about the report. Under the terms of the super-injunction the paper was not even allowed to write about being gagged. But Trafigura probably overplayed its hand when it also wanted to stop the British parliament from debating the issue, arguing that the parliamentarians would be interfering with the legal process. The parliament was in an uproar. The speaker of the Lower House has announced a debate will be held on Wednesday about the use of super-injunctions to gag the media. On Friday, the firm's lawyers backtracked and sent the Guardian a note allowing them to ignore the super-injunction. By then the report had already been published by media in other countries, and on the social networking platform Twitter. It was originally commissioned by Trafigura from a London consultancy firm, and suggested that the firm had known all along about the health risks posed by the waste from the Probo Koala. Trafigura has said the report was preliminary, and the information in it was later proved wrong. The company's CEO, Eric de Turckheim, said after the settlement with the plaintiffs last month that his company has now been completely exonerated.