Diesel engine exhaust fumes can cause cancer in humans and belong in the same potentially deadly category as asbestos, arsenic and mustard gas, according to the World Health Organisation (WHO).
In an announcement that caused consternation among car and truck makers, the France-based International Agency for Research on Cancer (IARC), part of the WHO, reclassified diesel exhausts from its group 2A of probable carcinogens to its group 1 of substances that have definite links to cancer.
The experts, who said their decision was unanimous and based on "compelling" scientific evidence, urged people across the world to reduce exposure to diesel fumes as much as possible.
"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.
It puts diesel fumes in the same risk category as noxious substances such as asbestos, arsenic, mustard gas, alcohol and tobacco.
IARC working group chairman Christopher Portier said the 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 becoming increasingly popular in Europe, where tax advantages have encouraged technological advances and a boom in demand.
Diesel makes up 73 per cent of the new cars sold in Ireland this year.
Outside of Europe and India, diesel engines are almost entirely confined to commercial vehicles. German carmakers are trying to raise awareness for diesels in the United States, where the long distances travelled suit diesel engines.
Reuters