Diesel engine exhausts cause cancer in humans, World Health Organization experts said on Tuesday in a decision which raises the risk rating of diesel fumes based on evidence of links to lung and bladder cancer.
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 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," IARC 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 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.