Six Common Air Pollutants

There are six air pollutants that are commonly found throughout the United States. The six pollutants are ozone, carbon monoxide, nitrogen dioxide, particulate matter, sulfur dioxide and lead.

These pollutants can injure health, harm the environment, and damage property. The U.S. Environmental Protection Agency (EPA) calls these air pollutants "criteria pollutants". The EPA has regulated these six pollutants by first developing health-based standards (primary standards) intended to protect our health. The EPA has also established welfare standards (secondary standards) that are designed to prevent environmental and property damage. The primary and secondary standards are referred to as National Ambient Air Quality Standards (NAAQS). A geographic area that meets or does better than the primary standard is called an attainment area; areas that do not meet the primary standard are called nonattainment areas.

Click on one of the pollutants below for information on sources and the health and environmental effects of the pollutant.

Ozone| Particulate Matter| Sulfur Dioxide
Carbon Monoxide| Nitrogen Dioxide| Lead