Diesel engine fumes can cause lung cancer and belong to the same deadly category as asbestos, arsenic and mustard gas, the World Health Organisation (WHO) experts said. In an announcement that caused concern in the auto industry, 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 one of substances which have definite links to cancer. The experts, who said their decision was unanimous and based on compelling scientific evidence, urged the people worldwide to reduce their exposure to diesel fumes as much as possible. “The 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 was the 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 considers diesel exhaust fumes in the same 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.