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Health and Environmental Effects of Hazardous Air Pollutants

People exposed to toxic air pollutants at sufficient concentrations and durations may have an increased chance of getting cancer or experiencing other serious health effects. These health effects can include damage to the immune system, as well as neurological, reproductive (e.g., reduced fertility), developmental, respiratory and other health problems. In addition to exposure from breathing air toxics, some toxic air pollutants such as mercury can deposit onto soils or surface waters, where they are taken up by plants and ingested by animals and are eventually magnified up through the food chain. Like humans, animals may experience health problems if exposed to sufficient quantities of air toxics over time. 

Health and ecological effects resources

  • The Health Effects Notebook for Hazardous Air Pollutants - Detailed information about the health effects of hazardous air pollutants (HAPs) is available in separate fact sheets, for nearly every HAP specified in the Clean Air Act Amendments of 1990.
  • Mercury - Learn more about mercury and what is being done to protect your health.
  • Risk Assessment - Learn about EPA Risk Assessments