120 Million Americans Exposed To Unhealthy Levels Of Smog And Soot

Nearly 120 million people in the United States — or more than one in every three — are exposed to unhealthy levels of air pollution, according to an annual report from the American Lung Association.

Many studies have shown that exposure to ozone, or smog, and fine particle pollution, or soot, increases the risk of premature birth, causes or worsens lung and heart disease and shortens lives.

The burden is not shared equally. More than 64 million, or 54%, of the people who live in areas with unhealthy air quality are people of color, according to the 2023 State of the Air report.

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The report grades Americans’ exposure to unhealthy levels of ground-level ozone air pollution, annual particle pollution and short-term spikes in particle pollution over a three-year period in cities and counties. This year’s report covers 2019-21.

It said overall air quality across the U.S. had improved.

“The good news is that ozone pollution has generally improved across the nation, thanks in large part to the success of the Clean Air Act. In this year’s ‘State of the Air’ report, we found that 19.3 million fewer people are living in areas with unhealthy levels of ozone pollution, also known as smog,” Harold Wimmer, national president and CEO of the American Lung Association, said in a news release.

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Ten of those counties were in California, which saw more than 9,000 wildfires in 2021. Smoke from wildfires is a major source of tiny particulate matter pollution called PM2.5.

In addition to fueling wildfires, climate change is leading to higher temperatures that are generally associated with higher ozone levels. The smog it produces is a powerful lung irritant that can lead to inflammation, trigger asthma attacks and cause other significant health problems.

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Ten of the 25 most ozone-polluted cities are also in California.

The top four are Los Angeles-Long Beach, Visalia, Bakersfield and Fresno-Madera-Hanford. Phoenix-Mesa, Arizona, is No. 5.

Seven cities rank on all three cleanest cities lists for particle pollution and ozone. They had zero days high in particle pollution or ozone and are among the 25 cities with the lowest year-round particle levels.

Alphabetically, they are: Asheville-Marion-Brevard, North Carolina; Bangor, Maine; Greenville-Kinston-Washington, North Carolina; Lincoln-Beatrice, Nebraska; Rochester-Batavia-Seneca Falls, New York; Urban Honolulu, Hawaii; and Wilmington, North Carolina.

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