Mobile source air toxics are emissions from highway vehicles and nonroad equipment, which are known or suspected to have serious negative effects on human or environmental health.

Mobile sources are responsible for direct emissions of air toxics and contribute to precursor emissions which react to form secondary pollutants. Examples of mobile source air toxics are benzene, formaldehyde, naphthalene and diesel particulate matter.

EPA is working to reduce hazardous air pollutants from mobile sources by limiting benzene content of gasoline and reducing toxic emissions from vehicles and gas cans; adopting mobile source emission control programs that aim to control and reduce air toxics; and developing programs to reduce diesel particulate matter.

To learn more about mobile source air toxics and what EPA is doing to reduce them, visit the links below.