Why worry about diesel exhaust?
Diesel exhaust is a significant source of fine particle pollution, as well as a combination of more than 40 substances that are listed as hazardous pollutants. Because of their microscopic size, these fine particles can become trapped in the small airways of the lungs when they are inhaled. Sources of diesel emissions include diesel-powered trucks, buses and cars (on-road sources); diesel-powered marine vessels, construction equipment, trains and aircraft support equipment (non-road sources). Particulate matter from diesel exhaust overwhelmingly presents the highest health risk in the Puget Sound area, making up an estimated 78 percent of the potential cancer risk from exposure to outdoor air toxics.1 Diesel particulate matter is also linked with health effects including heart problems, aggravated asthma, chronic bronchitis and premature death. Additionally, diesel fuel combustion produces smog-causing oxides of nitrogen. Smog causes breathing difficulties, eye irritation and reduced r
