World Bulletin / News Desk
Diesel engine exhaust fumes cause cancer in humans and belong in the same potentially deadly category as asbestos, arsenic and mustard gas, World Health Organisation (WHO) experts said on Tuesday.
The experts, who said their findings were unanimous and based on "compelling" scientific evidence, urged people across the world to reduce their exposure to diesel fumes wherever possible.
In an announcement likely to cause consternation among car and truck makers, the International Agency for Research on Cancer (IARC), the WHO's cancer department, reclassified diesel exhausts from its group 2A of probable carcinogens to its group 1 of substances that have definite links to cancer.
"The (expert) working group found that diesel exhaust is a cause of lung cancer and also noted a positive association with an increased risk of bladder cancer," it said in a statement.
The decision is a result of a week-long meeting of independent experts who assessed the latest scientific evidence on the cancer-causing potential of diesel and gasoline exhausts.
The decision puts diesel fumes in the same IARC risk category as a number of other noxious substances including asbestos, arsenic, mustard gas, alcohol and tobacco.
Christopher Portier, chairman of the IARC working Group, said the group's conclusion "was unanimous - that diesel engine exhaust causes lung cancer in humans".
"Given the additional health impacts from diesel particulates, exposure to this mixture of chemicals should be reduced worldwide," he said in a statement.
Diesel cars are mainly popular in western Europe, where advantageous tax treatments have helped trigger technological advances and a boom in demand.
Outside of Europe and India, diesel engines are almost entirely confined to commercial vehicles - mostly because of the fuel's greater efficiency. German carmakers are trying to raise awareness for diesels in the United States, where the long distances travelled on highways suit diesel engines.
For about 20 years, diesel engine exhaust was defined by IARC as probably carcinogenic to humans - group 2A - but an IARC advisory group has repeatedly recommended diesel engine exhaust as a high priority for re-evaluation since 1998.
Reacting to IARC's decision, Allen Schaeffer, executive director of the Washington DC-based Diesel Technology Forum said diesel engine and equipment makers, fuel refiners and emissions control technology makers have invested billions of dollars in research into technologies and strategies to reduce emissions.
"New technology diesel engines, which use ultra-low sulphur diesel fuel, advanced engines and emissions control systems, are near zero emissions for nitrogen oxides, hydrocarbons and particulate matter," he said in a statement.
The group said gasoline exhaust fumes should be classified as "probably carcinogenic to humans", a finding that was unchanged from the previous IARC assessment made in 1989.