WHO says diesel exhaust can cause cancer

Exhaust from diesel engines can cause cancer, a prominent global cancer group that's part of the World Health Organization said Tuesday.

The decision could put pressure on governments to introduce stricter limits on emissions, especially to protect workers who are exposed to diesel exhaust while on the job.

The International Agency For Research On Cancer (IARC) has for more than two decades classified diesel engine exhaust as a "probable" carcinogen -- a cancer-causing agent -- but until recently there was no clear evidence linking it to higher cancer rates.

This spring, however, two studies were published based on research done by the National Cancer Institute and involving more than 12,000 mine workers, known as the Diesel Exhaust in Miners Study, or DEMS. Together, the two new papers found an increase in lung cancer rates among workers exposed to diesel exhaust underground, with greater exposure linked to steadily higher cancer rates. In workers with the highest exposure, deaths from lung cancer were nearly triple.