All countries have to deal with emissions from diesel vehicles, but African nations have it worse than most.
They often have few emissions regulations, something Swiss trading firms take advantage of by importing fuel that's too dirty for sale in other regions.
These firms often serve as both producer and distributor for fuels in Africa, according to a new study by Swiss advocacy group Public Eye.
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Titled "Dirty Diesel," the full report (pdf) argues that Swiss trading firms like Trafigura, Vitol, and Addax & Oryx take advantage of lax regulations to dump the dirtiest diesel and gasoline on African nations.
The 160-page report is based on three years of research into the African fuel trade.
Researchers sampled fuel directly from pumps in eight countries, and found that samples contained up to 378 times the sulfur permitted under European regulations.
Oil well (photo by John Hill)
Other toxic substances—including benzene and polycyclical aromatic hydrocarbons—were also found in concentrations banned in Europe, according to the study.
Swiss trading firms often make these high-pollution fuels themselves, producing grades known as "African Quality" that are sometimes also sold through fuel stations controlled by the companies.
While these fuels are intended for sale in Africa, they are produced in the "ARA (Amsterdam-Rotterdam-Antwerp) Zone" in Europe, where many of the trading firms have refineries.
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That means while West African nations export high-quality crude oil, they often receive low-quality fuels with high levels of pollutants in return.
In other regions, regulations would prohibit the sales of these fuels, but African standards are generally too lax to prevent the practice, according to Public Eye.
Until meaningful action is taken, citizens will have to live with the health effects of increased air pollution.
Public Eye cites a recent United Nations study, which concluded that Africa's major cities will likely see the most rapidly-increasing levels of air pollution in the world in the coming years.
By 2030, Africa will have three times as many deaths from vehicle-related air pollution as the U.S., Europe, and Japan combined.
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The compliance of poorer nations will likely be a major issue with global efforts to combat climate change—such as the much-publicized climate-change summit in Paris last year.
In addition to having less regulatory power, these nations are more likely to feel an acute economic impact from transferring their industries and infrastructure to cleaner energy sources.
[EDITOR'S NOTE: Green Car Reports thanks our tipster, who prefers to remain an International Man of Mystery.]