The US government’s National Institute for Occupational Safety and Health (NIOSH) recommended in1988 that diesel exhaust fumes should be regarded as potentially carcinogenic. A Current Intelligence Bulletin noted: “On the basis of the results of these studies, NIOSH recommends that whole diesel exhaust be regarded as ‘a potential occupational carcinogen,’ as defined in the Cancer Policy of the Occupational Safety and Health Administration (OSHA) (“Identification, Classification, and Regulation of Potential Occupational Carcinogens,” 29 CFR 1990). This recommendation is based on findings of carcinogenic and tumorigenic responses in rats and mice exposed to whole diesel exhaust. Though the excess risk of cancer in diesel-exhaust-exposed workers has not been quantitatively estimated, it is logical to assume that reductions in exposure to diesel exhaust in the workplace would reduce the excess risk.” The bulletin added: “NIOSH recommends that producers of diesel engines disseminate this current information to their customers, and that users of diesel-powered equipment disseminate this current information to their workers. NIOSH also recommends that professional and trade associations and unions inform their members of the new findings of potential carcinogenic hazards of exposure to diesel engine emissions, and that all available preventive efforts (including available engineering controls and work practices) be vigorously implemented to minimize exposure of workers to diesel exhaust.” In 2012, IARC reclassified diesel exhaust fumes as proven cause of cancer in humans. Had NIOSH’s recommendations on preventive action been acted on 24 years earlier, then many of the many hundreds of UK deaths each year attributed to occupational diesel exhaust exposure could have been avoided. [also see: HSE falls 1,000 short on diesel cancer deaths estimate, December 2013].

Carcinogenic effects of exposure to diesel emissions, NIOSH Current Intelligence Bulletin, Number 50, August 1988.