Diesel exhaust is joining asbestos, radon and smoking in a rare but dangerous group: things that cause lung cancer.
Exposure to heavy amounts of diesel exhaust has been linked to lung cancer deaths in miners, according to a recently released study from the National Cancer Institute (NCI).
The results were detailed in two research papers published in a March issue of the Journal of the National Cancer Institute and on its website on March 2.
Lung cancer, a disease that accounts for the most cancer-related deaths, has traditionally been associated with smoking, radon and asbestos exposure. The NCI’s 20-year study now lists heavy exposure to diesel exhaust among the ranks of these other toxins linked to lung cancer.
Like other asbestos-related diseases, lung cancer has risk factors that are tied to certain occupations. For example, because miners spend so much time working in an enclosed environment, diesel exhaust from mining machines builds up and leads to a higher risk of lung cancer among miners.
Conducted by researchers from the NCI, National Institutes of Health (NIH) and National Institute for Occupational Safety and Health (NIOSH), the study involved 12,315 workers in eight non-metal mining facilities.
The mining locations included one limestone mine in Missouri, three potash mines in New Mexico, one salt mine in Ohio and three trona mines in Wyoming.
Non-metal mines were selected because of their statistically lower levels of other lung cancer risk factors such as asbestos, radon and silica. Researchers further controlled the results by removing smoking as a contributor.
Miners who were heavily exposed to diesel exhaust demonstrated a risk of cancer death three times that of workers who had lower exposure levels. Still, miners with lower exposures showed a 50 percent increase risk of developing cancer compared to non-exposed workers.
Research results provide occupational scientists an opportunity to improve conditions for miners of all types.
“Our findings are important not only for miners but also for the 1.4 million American workers and the 3 million European workers exposed to diesel exhaust, and for urban populations worldwide,” said Debra Silverman, an epidemiologist at the NCI.
Researchers from the Occupational and Environmental Epidemiology Branch in the Division of Cancer Epidemiology and Genetics (DCEG) participated in the composition of one of the two papers that featured the study’s results.
“This landmark study has informed on the lung cancer risks for underground mine workers, but the findings suggest that the risks may extend to other workers exposed to diesel exhaust in the United States and abroad, and to people living in urban areas where diesel exhaust levels are elevated,” said Joseph F. Fraumeni of the DCEG.
Some reports have stated that mining companies have used litigation of the results as a method to delay the release of the study. The argument has been stated that the report results don’t account for recent upgrades in diesel machines which emit less amounts of exhaust.