Air quality in Denver is getting worse

Air quality has deteriorated across the Denver metro area since 2015, the latest data from the Environmental Protection Agency shows.

• Last September, the EPA officially downgraded the Front Range from a "serious" to "severe" air quality violator after repeated offenses of federal ozone standards.

State of breathing: Colorado's peak season for ozone starts in June, when state health officials begin issuing pollution alerts for the Front Range that run through August.

Why it matters: Fine particles, generated from fossil fuel-burning and other sources, can enter our bodies when we breathe, making their way to the lungs or bloodstream and causing myriad health problems, Axios' Alex Fitzpatrick and Kavya Beheraj report.

• They are linked to nearly 11,000 needless deaths across the U.S. annually, and put non-white and low-income Americans at higher risk.

By the numbers: The three-year rolling annual average concentration of fine particle pollution across the Denver area was 8.1 micrograms per cubic meter as of 2021 compared to 6.7 in 2015 — a 21% increase, though still below the national average of 8.5 micrograms per cubic meter.

• Other Front Range cities also saw their air quality worsen. Air pollution levels spiked by 26% in Greeley and 20% in Boulder.
• Concentrations below 12 micrograms per cubic meter are considered healthy, the EPA says — though it is seeking to tighten that standard.

What's happening: Most of the ozone along the Front Range is a result of a few factors, including vehicle emissions, industrial factories, wildfires and Denver's bowl-like topography, which traps pollutants.

• Last month, the Suncor oil refinery in Commerce City spewed hazardous chemicals into the surrounding neighborhood, marking its second chemical leak in April.

What's next: State lawmakers are pushing a bill aimed at combating ozone pollution levels, though it was significantly weakened under pressure from the Polis administration and the oil and gas industry.

The intrigue: Some parts of the state saw improvements in air quality, including Grand Junction, where pollution levels dropped by 22% as well as Colorado Springs, which saw a 2% dip.

What's next: State lawmakers are pushing a bill aimed at combating ozone pollution levels, though it was significantly weakened under pressure from the Polis administration and the oil and gas industry.

The big picture: Air quality generally improved in Denver and nationwide during the height of the pandemic, in part because fewer people were driving.

• But as the pandemic ebbs and people's behaviors and activities return to normal, air quality nationally is worsening accordingly.

Go deeper: Explore the national interactive map