At the witness stand in the Amsterdam courtroom, Trafigura steers the truth as ruthlessly as it steered the Probo Koala. Trafigura’s defence lawyer declared that all the damages caused by refining at sea of Petroleos Mexicanos’ hyper sulphurized naphtha and all the health risks from the desulphurization waste could be only a “myth” spread by ecologists, journalists, and politicians. In his opening defence he stated that “It has not been proven that the events in the Ivory Coast [the spreading of Probo Koala’s waste in Abidjan] cause serious harm to the health of the population, or that they could have done”.
Are the risks of mercaptan and hydrogen sulphide also a scientific myth?
The accident analysis of mercaptan listed on the ARIA database counts 54 incidents not including the accident on April 8, 1970 when 3 railway workers died in Lacq next to a wagon leaking of mercaptan. The accident statistics of hydrogen sulphide accounts for 112 fatalities which does not take into account the hydrogen sulphide resulting from the decay of green algae.
When they are not deadly, consequences of inhaling air polluted by mercaptans and hydrogen sulphide such as they are presented in summaries of accidents or in toxicology fact sheets are completely identical to those found and reported after the events in Abidjan and those in Sløvåg where waste from Trafigura’s chain also caused a disaster in May, 2007.
Mercaptans can cause chest pain, coughing, nausea, migraines, vomiting and diarrhoea. Hydrogen sulphide causes respiratory problems, pulmonary edemas and in small doses conjunctivitis, rhinitis, eye irritations and nosebleeds. Hydrogen sulphide gives off an odour of rotten eggs and the four mercaptan compounds give off an odour of rotten leek, garlic, cabbage and that of a skunk. One would think that we are in Abidjan from August to September in 2006.
Analysis carried out in Amsterdam by the Dutch Forensic Institute and in Abidjan by CIAPOL (Centre Ivorien Anti-Pollution) show very high levels of mercaptan and hydrogen sulphide: levels of hydrogen sulphide range from 5,000 mg/kg to 6,129 mg/kg and mercaptan range from 1,287 mg/kg to 35,000 mg/kg. The dumping of waste with high sulphur contents in an acidic environment such as polluted waters or open gutters and the exposure to rain facilitate formation and release of toxic gases. At these levels, they are susceptible to reach concentrations in the air triggering lethal, irreversible or chronic risks, these risks would continue during certain weather conditions such as the absence of wind.
Broadly speaking, the overall health assessment of the disaster in Abidjan should also take into account the collateral effects of the Probo Koala’s waste like the closing of the dump in Akouedo and the consecutive stop of household waste collection in the greater Abidjan region. Trafigura is also responsible in this area, as they choose to unload their waste in Abidjan with full knowledge of the dangers involved.
Exposition environnementale à des déchets contenant du mercaptan, des hydrocarbures aromatiques et de l’hydrogène sulfuré (Abidjan). K. Dongo, A. B. Koné, I. Tiembré, J. Biémi, M. Tanner, J. Zinsstag, G. Cissé. Environnement, Risques & Santé – Vol 8, n°6, novembre-décembre 2009.
Déchets toxiques déversés à Abidjan (Côte d’Ivoire) et conséquences sanitaires. X. Bohand, C. Monpeurt, S. Bohand, A. Cazoulat. Médecine Tropicale. 2007. 67 : 620-624.
Seuils de toxicité aiguë – Hydrogène Sulfuré (H2S). Rapport final INERIS. Janvier 2000.