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Urban Air Toxic Pollutants

There are 187 hazardous air pollutants (HAPs) that EPA is required to control. From these HAPs, EPA identified 30 that pose the greatest potential health threat in urban areas. These HAPs are referred to as the 30 urban air toxics. EPA also identified an additional three HAPs, but these HAPs are not generally emitted by area sources and, as such, were not included as part of the 30 urban air toxics. The three additional HAPs are coke oven emissions, 1,2-dibromoethane and carbon tetrachloride.

List of 30 Urban Air Toxics
Acetaldehyde Dioxin Mercury compounds
Acrolein Propylene dichloride Methylene chloride (dichloromethane)
Acrylonitrile 1,3-dichloropropene Nickel compounds
Arsenic compounds Ethylene dichloride (1,2-dichloroethane) Polychlorinated biphenyls (PCBs)
Benzene Ethylene oxide Polycyclic organic matter (POM)
Beryllium compounds Formaldehyde Quinoline
1,3-butadiene Hexachlorobenzene 1,1,2,2-tetrachloroethane
Cadmium compounds Hydrazine Tetrachloroethylene (perchloroethylene)
Chloroform Lead compounds Trichloroethylene
Chromium compounds Manganese compounds Vinyl chloride