Healthy Air

How bad is air pollution in Colorado?

New American Lung Association report paints a less than rosy picture

Clean air

An oil refinery near Denver, Colorado
Braden Gunem | | Used by permission
An oil refinery in the Denver area

During Earth Week 2024, the American Lung Association released their 25th annual “State of the Air” Report. The report analyzes data from official air quality monitors across the country and ranks and grades American cities and counties based on their levels of pollutants such as ozone and particulate matter.

Unfortunately, the 2024 report showed high levels of both forms of air pollution in Colorado. Some of the findings:

  • Eleven Colorado counties received “F” grades for ozone pollution – including all counties in the Denver Metro area, for the third year in a row. Five Colorado counties received failing grades for particle pollution.
  • For the second year in a row, Colorado has three cities listed among the top 20 most polluted in the nation when it comes to unhealthy levels of ozone pollution: Denver-Aurora (6th), Fort Collins (16th) and Colorado Springs (20th).
  • Three metro area counties were among the worst counties for ozone nationally: Jefferson County (8th), Douglas County (10th), and Arapahoe County (18th).
  • In total, 80% of Colorado residents live in a community with unhealthy air, compared with 39% nationally.

Ground-level ozone pollution forms when nitrogen oxides (NOx) and volatile organic compounds (VOCs) combine chemically in the presence of sunlight. Exposure to ozone can cause harmful health effects including lung damage, worsening of existing respiratory conditions such as asthma, and even cardiovascular disease. For its part, particle pollution has been linked to respiratory ailments, reproductive and mental health issues, and even premature death

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