A study by the National Cancer Institute has found people might have an increased risk of developing lung cancer because of exposure to even low levels of diesel exhaust. Here is some key information from the study.
* The study was published in the Journal of the National Cancer Institute, according to Health Canal.
* It was conducted through the auspices of the National Institutes of Health and the National Institute for Occupational Safety and Health. NIOSH operates under the umbrella of the Centers for Disease Control and Prevention.
* The study was conducted over 20 years, using 12,315 miners working in nonmetal mines. Nonmetal mines are low in other known pollutants such as radon, silica and asbestos.
* Researchers also controlled for other factors known to increase a person's cancer risk such as smoking.
* Miners were chosen because the equipment used underground runs on diesel fuel so exposure to exhaust is higher than in the rest of the population.
* The study found miners who had the highest degree of exposure were more than three times as likely to develop lung cancer and significantly more likely to die because of it, according to the Los Angeles Times.
* Miners who had the lowest exposure to diesel exhaust were 50 percent more likely to develop lung cancer.
* Those measured on the low-end had exposure to diesel exhaust that mimicked that of people who live in urban environments, according to the Associated Press.
* Researchers who worked on the study, including NCI epidemiologist Debra Silverman, maintain the results have implications beyond just risks to miners. Silverman and her colleagues said the study shows there are risks to all workers who are exposed to diesel exhaust as well as people in urban environments.
* The study was the subject of litigation resulting from accusations that its research was not up to date. Opponents maintain diesel equipment in many mines has been upgraded in the last few years to emit less exhaust.
* The International Agency for Research on Cancer is expected to weigh in later this year on whether the designation for diesel exhaust should be changed from "probable carcinogen" to "known carcinogen," according to the Los Angeles Times.
Vanessa Evans is a musician and freelance writer based in Michigan, with a lifelong interest in health and nutrition issues.