Common health effects of exposure to even low levels of air pollutants are irritated eyes and inflammation of the respiratory tract. There is some evidence that exposure to air pollutants suppresses the immune system, increasing susceptibility to infections.
Pollutant |
Source |
Health Effects |
Particulate matter |
Industries, electric power plants, motor vehicles, construction, agriculture |
Aggravates respiratory illnesses; long-term exposure may cause increased incidence of chronic conditions such as bronchitis; suppresses immune system; heavy metals and organic chemicals may cause cancer |
Nitrogen oxides |
Motor vehicles, industries, heavily fertilized farmland |
Irritate respiratory tract; aggravates asthma and chronic bronchitis |
Sulfur oxides |
Electric power plants and other industries |
Irritate respiratory tract; long-term exposure may cause increased incidence of chronic conditions such as bronchitis; suppresses immune system; heavy metals and organic chemicals may cause cancer |
Carbon monoxide |
Motor vehicles, industries, fireplace |
Reduces blood’s ability to transport oxygen; low levels cause headaches and fatigue; higher levels cause mental impairment or death |
Ozone |
Formed in atmosphere |
Irritates eyes and respiratory tract produces chest discomfort; aggravates asthma and chronic bronchitis |