Outdoor air provides humans with oxygen, which is essential to human life. But the outdoor air we breathe can be polluted with chemicals from vehicles, electric power plants, incinerators, and other sources. Air pollution can also come from natural sources such as forest fires, industrial sources such as chemical plants and factories, and smaller sources such as dry cleaners and gas stations. 

Air pollution can cause many harmful health effects, including asthma, heart disease, and cancer. Some air pollutants can be more harmful to human health than others. Some people, especially children and the elderly, are more vulnerable to the health effects of air pollution than others. Common air pollutants include ozone, which can cause asthma and respiratory problems; particulate matter, which can cause lung damage; sulfur dioxide, which can cause breathing problems; and volatile organic compounds, which can cause cancer. 

Hazardous air pollutants are known or suspected to cause cancer, reproductive problems, birth defects, or other serious health effects. They are also called air toxics, or toxic air pollutants. The U.S. Environmental Protection Agency (EPA) is working to reduce the amounts of 188 toxic air pollutants, including asbestos, benzene, mercury, perchloroethylene, and toluene.

This description is based on the information found in the Web links listed with this topic.

Web Links from MedlinePlus (National Library of Medicine)
Air Pollution
Fires
Ozone

More Links
Air Info Now Activities: CO City; Lung Attack; Recipe for Ozone (University of Arizona)
Air Pollution (Agency for Toxic Substances and Disease Registry)
Air Quality Where You Live (Environmental Protection Agency)
Air Trends - Basic Information (Environmental Protection Agency)
Air Trends home page (Environmental Protection Agency)
AirCompare (Environmental Protection Agency)
Enviro-Health Links - Outdoor Air (National Library of Medicine)
Navajo Coal and Air Quality in Shiprock, New Mexico (US Geological Survey) (PDF — 797.43 KB)
Outdoor Air Pollution. Environmental Health Student Portal (National Library of Medicine)
Radionuclides in Air (Environmental Protection Agency)
Taking Toxics Out of the Air (Environmental Protection Agency)
Wildfires (Centers for Disease Control and Prevention)

Chemicals in the Air
Are these chemicals in MY community?
Acetone
Ammonia
Asbestos
Benzene
Cadmium
Carbon Dioxide
Carbon Monoxide
Chlorofluorocarbons (CFCs)
Diesel
Dioxins
Endocrine Disruptors
Formaldehyde
Gasoline
Mercury
Methane
Methanol
Nitrogen Oxides
Ozone
Particulate Matter
Perchlorate
Perchloroethylene (PCE, PERC)
Persistent Organic Pollutants (POPs)
Pesticides
Polybrominated Diphenyl Ethers (PBDEs)
Polycyclic Aromatic Hydrocarbons (PAHs)
Polyvinyl Chloride (PVC)
Solvents
Styrene
Sulfur Dioxide
Toluene
Volatile Organic Compounds (VOCs)

Last Updated: December 10, 2012