Three Colorado cities are going in the wrong direction when it comes to cleaner air.

For the fifth year in a row, metro Denver moved up in the American Lung Association’s rankings for the most polluted cities in the United States when it comes to ozone pollution. Fort Collins also once again jumped in the rankings, released by the lung association on Wednesday.

Metro Denver ranked No. 6, up one spot from 2022, while Fort Collins climbed to No. 15, moving up three places from the previous year, according to the association’s 2023 report.

And Colorado Springs made its debut at No. 20 after Detroit and Chico, California, improved enough to drop out of the rankings, according to the report.

The annual report by the American Lung Association comes as Colorado’s leaders continue to offer various plans to bring down the state’s air pollution levels while also balancing the demand for oil and gas that fuels hundreds of thousands of vehicles on the road and powers various industries.

But the high pollution levels threaten public health. The American Lung Association says ozone pollution causes breathing disorders such as asthma and lung cancer and also contributes to pre-term births and low birth weights as well as heart attacks and strokes.

Environmentalists argue the state is not doing enough to fix the problem.

The state’s climb up the rankings has been consistent.

Metro Denver ranked eighth-worst for ozone in 2021, up from 10th in 2020 and 12th in 2019, according to a compilation of federal data by the American Lung Association

Denver only falls behind four metro areas in California and Phoenix when it comes to poor air quality. A total of 227 metro areas are measured each year in the rankings.

Metro Denver also ranked 18th worst for 24-hour particle pollution out of 223 metro areas and 27th worst for annual particle pollution out of 200 metro areas. Twenty-four-hour particle pollution counts short-term spikes such as periods when wildfire smoke blankets the state while annual particle pollution collects data for the year.

This is the first year the Denver area landed on the short-term particle pollution list, the report said.

Wildfires in the western U.S. are a major contributing factor to the increasing number of days and places with unhealthy levels of particle pollution, the lung association’s report said. They are also increasing the severity of pollution, leading to more days when people are warned about going outside for exercise or work.

The Front Range in late 2022 was labeled in “severe non-attainment” by the Environmental Protection Agency after it once again failed to meet National Ambient Air Quality standards. That label will cause gas prices to rise in the summer and will lead hundreds of businesses to need federal air permits because they will now be considered major sources of pollution.

State officials know the state has an ozone problem, and multiple measures are in the works to make improvements, including placing tougher regulations on emissions from the oil and gas industry, which accounts for about half of the state’s ozone pollution.

On Wednesday, the state’s Air Quality Control Commission held a public hearing on a clean-truck strategy that would push semitrailers, buses and delivery vehicles toward electrification. Dozens of people spoke in favor of the rule, citing asthma problems and other health threats.

Natalia Ekberg, an Arvada resident, urged the commission to pass the rule because her children’s school is about 2,000 feet from Interstate 70. She worried about soot and exhaust from the heavy trucks and what impact it has on students.

“We can’t change the location of the school, but we can change the rules,” she said.

Cayenna Johnson, a Denver mother whose teenage son has severe asthma, said forcing heavy trucks to convert to electrification would improve air quality and her son’s health. She described all the equipment in their home to help him breathe and counted numerous hospital visits all because of her son’s illness.

“If there is any bad air quality and he gets a cold, he’s out of school at least a week or more,” Johnson said. “I cannot emphasize what an impact our air quality has on his life.”

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