Britannica
Sources used in this answer
Which six pollutants are regulated as criteria air pollutants in the United States?
Created from Britannica articles
using AI.
AI can make mistakes, so verify using Britannica articles.
air pollution control
Even something as simple as breathing can get complicated.
The U.S. Environmental Protection Agency (EPA) designates six substances as "criteria" air pollutants, meaning their atmospheric concentrations serve as indicators of overall air quality. These pollutants are regulated under the Clean Air Act through National Ambient Air Quality Standards to protect public health and the environment.123
The six criteria air pollutants are:
- Carbon monoxide (CO)
- Lead (Pb)
- Nitrogen dioxide (NO₂)
- Particulate matter
- Sulfur dioxide (SO₂)
- Ground-level ozone (O₃)23
These pollutants are monitored because of their significant impact on human health, such as respiratory irritation and cardiovascular issues, as well as their role in environmental damage, including the formation of smog and acid rain.13