Colorado Adopts Health-Protective Benchmarks for Five Toxic Air Pollutants

Strategic Insights -

The Colorado Air Quality Control Commission has adopted health-protective benchmarks for benzene, ethylene oxide, formaldehyde, hexavalent chromium compounds, and hydrogen sulfide, meeting a legislative mandate and providing science-based guidance for evaluating long-term exposure to priority air toxics. The benchmarks identify levels of pollutants below which adverse health effects are not expected to occur, including for children, older Coloradans, and people with existing health conditions. This achievement marks a significant step in protecting public health and reducing the risks associated with toxic air pollutants.

Key Takeaways:

  • The Colorado Air Quality Control Commission has adopted health-protective benchmarks for five toxic air pollutants: benzene, ethylene oxide, formaldehyde, hexavalent chromium compounds, and hydrogen sulfide.
  • The benchmarks meet a requirement set forth in the Public Protections from Toxic Air Contaminants Act (HB 22-1244) and provide science-based guidance for evaluating long-term exposure to priority air toxics.
  • The benchmarks consider both cancer and non-cancer risks, and are based on continuous lifetime exposure with a margin of safety.
  • The Air Pollution Control Division consulted a technical working group and evaluated how other states developed similar benchmark values.
  • The standards will be submitted to the Colorado General Assembly in December 2025, as required under HB 22-1244.
  • The Air Pollution Control Division is also seeking feedback on a related report exploring whether a permitting program could use these benchmarks to calculate risks and require actions to reduce exposure.
  • Every five years, the Air Quality Control Commission will review the benchmarks and may identify additional priority air toxics.

Statistics:

  • The new benchmarks provide health-protective guidance for evaluating long-term exposure to priority air toxics.
  • The Air Pollution Control Division consulted a technical working group, comprised of 15 experts, to gather input on the development of the benchmarks.
  • According to the Air Quality Control Commission, the benchmarks consider both cancer and non-cancer risks, with a margin of safety for continuous lifetime exposure.
  • The Air Quality Control Commission will review the benchmarks every five years to determine if additional priority air toxics should be identified.

Sources:

  • Colorado Department of Public Health and Environment (CDPHE)
  • Press Release: "Commission Approves Health Benchmarks for Five Toxic Air Pollutants"
  • Public Protections from Toxic Air Contaminants Act (HB 22-1244)
  • Rulemaking Hearing Materials
  • Priority Air Toxics Web Page