The Clean Air Task Force (CATF) compiled a fact sheet about dangerous health effects of diesel exhaust. In its review of published studies, the non-profit group found that diesel exhaust may cause heart disease, stroke and various respiratory illnesses, as well as bladder, colon and lung cancer.
It's not just diesel exhaust that's dangerous, and it's not just an occupational hazard.
Various studies have found that automobile exhaust is linked to the same conditions as diesel exhaust, and Dan Greenbaum of the Health Effects Institute says that 30 per cent to 45 per cent of people in North America are regularly exposed to high levels of exhaust from major roadways.
A 2007 Harvard University study found that workers in the trucking industry have much higher rates of cardiovascular disease than the general public.
Truck drivers have a 49 per cent higher risk; shop workers are 34 per cent more likely to have heart disease, and dockworkers have a 32 per cent higher rate of cardiovascular disease.
In 2004, particulate inhalation was linked to irregular heart rates and indication of vascular inflammation in highway patrolmen.
Studies published in the 2003 journal Circulation and the 2006 Journal of Occupational and Environmental Medicine found that particulate inhalation increased the risk of stroke.The second study found that stroke risk more than doubled with just two hours of exposure.
Dr. Andre Nel, lead researcher in a UCLA study in 2007, found that automobile exhaust particles combined with cholesterol in the body, triggering genetic alterations that led to inflammation and plaque build-up in blood vessels. Deaths from heart disease increase when air pollution levels rise.
In 2010, the Health Effects Institute reviewed existing research and reported that "strong evidence" exists that traffic exhaust increases rates of heart disease.
The Health Effects Institute review determined that car exhaust exacerbates asthma in children.
The CATF reported that diesel particles have been linked many times to asthma, allergic sensitisation and symptoms, chronic bronchitis and other respiratory infections.
Diesel exhaust has been internationally recognised as a carcinogen, says the CATF. The group also reported that a 38-year Harvard study of railroad workers discovered a 49 per cent increased rate of lung cancer across 30 different railway jobs.
The 2007 Harvard study of truck industry workers also found that they had a 10 per cent increased risk of developing lung cancer, and a National Institute of Occupational Safety and Health study found that lifetime risk of lung cancer in truckers is 10 times what OSHA limits deem allowable for occupational risk.
A review of exhaust exposure research published in Epidemiology found a link with bladder cancer in 10 of 12 studies. A 2001 study published in the American Journal of Industrial Medicine found that diesel exhaust was linked to a 50 per cent increased risk of colon cancer.
Ohio State University researcher Qinghua Sun discovered that diesel exhaust induces proliferation of blood vessels that feed cancerous tumours. The 2009 study looked at effects in both diseased and healthy rodents, and found that just a two-month exposure can make healthy tissue susceptible to tumour growth.
Exhaust particles also affect the central nervous system. A 2000 study published in the Archives of Environmental Health found that workers exposed to diesel fumes had impaired reaction times and balance, trouble with verbal recall, memory loss, disordered sleep and abnormal visual fields. The author concluded that "crews may be unable to operate trains safely."
Most exhaust particles are so small that they easily enter the bloodstream, organs and tissues, wreaking havoc throughout the body.
The CATF reported that three of the biggest and longest air pollution studies found a strong correlation between particle exposure and increased risk of death from heart and lung diseases.