What are Air Toxics?

Also know as Hazardous Air Pollutants (HAPs) or Toxic Air Contaminants (TACs) air toxics are pollutants that, at sufficient concentrations and exposure, are known or suspected to cause cancer, other serious health impacts, or damage to the environment.

There are three main types of air toxics:

• Gases. These include benzene, toluene, and xylenes, which are all found in gasoline.
• Liquid Aerosols. Perchloroethylene, a dry cleaning agent, and methylene chloride, an industrial solvent, are among these.
• Particulate matter. These microscopic particles may contain chemicals such cadmium, chromium, lead and mercury, and polycyclic aromatic hydrocarbons from the burning of fossil fuels and waste. (see PM2.5)

   

Air toxics can come from a variety of sources including cars, trucks and other mobile sources, all types of burning, business and industry, indoor sources (paints and solvents), and natural sources like volcanoes and wildfires. Generally, the toxic air pollutants of greatest concern are those released in amounts large enough to create a risk to human health or in areas where many people are likely to be exposed. Under the Clean Air Act, EPA is required to regulate emissions of 188hazardous air pollutants to the environment. There are 482 compounds that Colorado defines as toxic air contaminants, including hydrogen cyanide, hydrogen sulfide, benzene, and other toxic air contaminants listed in statute in Regulation 3.

CDPHE has an air toxics monitoring site in Platteville and collects measurements of some HAPs at the Weld County Missile Site Park air monitoring site. Phase I of the program became operational by January 1, 2024 with the first report expected by July 1, 2025. This report will be presented to the public in two outreach sessions to solicit comments on the monitoring program.

https://www.colorado.gov/airquality/air_toxics_repo.aspx