The report shows more days with “very unhealthy” and “hazardous” air quality than ever before in the two-decade history of this report. And it shows that people of color — who, largely because of discriminatory lending practices, might populate neighborhoods that historically share zip codes with industry or major, heavily-trafficked roads — are disproportionally impacted compared to white Americans.

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“More than 137 million Americans live in counties that had unhealthy levels of particle pollution or ozone. In addition, communities of color are disproportionately exposed to unhealthy air,” said Harold Wimmer, national president and CEO of the American Lung Association.

You can search your own area’s air quality by state, county, and metropolitan statistical area.

The report tracks and grades Americans’ exposure to unhealthy levels of short-term spikes in particle pollution (also known as soot), annual particle pollution and ground-level ozone air pollution (also known as smog) over a three-year period.

The report found that people of color were 61% more likely than white people to live in a county with a failing grade for at least one pollutant, and 3.6 times as likely to live in a county with a failing grade for all three pollutants.

The nonprofit group reups its arguments that the findings show climate change is degrading air quality in the U.S. Rising temperatures and other impacts associated with climate change contribute to more frequent and intense wildfire smoke, as well as making ozone air pollution more likely to form, it said.

Burning fossil fuels
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for heat, electrical power and transportation is the largest contributor to global warming. In 2019, fossil fuels were the source of about 74% of total U.S. human-caused GHG emissions, the Energy Information Agency says.

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Other health groups have heightened their concerns for climate change as well. Global warming packs the “greatest threat” to public health, argued an unprecedented joint statement issued last year from more than 200 U.S. and international medical journals. It was a release issued even during the height of the COVID-19 pandemic.

Hotter, drier conditions

On the positive side, the air report findings continue to show long-term improvement in the nation’s air quality, which the American Lung Association credits to “decades of work to reduce emissions.”

That progress, however, is offset in part by the negative impacts of hotter, drier conditions caused by climate change, the group said.

Wildfires in the western U.S. were responsible for a sharp rise in particle pollution spikes in several states. Overall, the report finds that 2.1 million more Americans live in counties with unhealthy air compared to last year’s report, and exposure to deadly particle pollution has gotten worse.

And for the first time, the Lung Association included Puerto Rico air pollution data, and listed pregnant people as a group at higher risk for harms associated with poor air quality.

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Particle pollution

Fine particulate matter air pollution can be deadly. These unhealthy particles in the air come from wildfires, wood-burning stoves, coal-fired power plants, diesel engines and other sources. Technically known as PM2.5, the microscopic particles can trigger asthma attacks, heart attacks and strokes, and cause lung cancer.

A scientific report independent of the American Lung Association showed that senior citizens who breathe in even low levels of pollution from industry, traffic, wildfires and other sources face greater odds of dying earlier as a result.

That study, which researchers argue is the first of its kind, was released earlier this year and involved an in-depth review of some 68.5 million Medicare recipients over four years. What’s more, it extended to people who live in rural areas and towns with little industry. The researchers said their findings suggest that incremental changes in emissions could save lives.

Unhealthy spikes

This year’s report finds an increase of close to 8.9 million more people living in areas with failing grades for unhealthy levels of short-term particle pollution compared to last year’s report. In total, 63.2 million people lived in counties that that earned an F for unhealthy spikes in particle pollution.

Top 5 cities most polluted by short-term particle pollution:
Fresno-Madera-Hanford, CA
Bakersfield, CA
Fairbanks, AK
San Jose-San Francisco-Oakland, CA
Redding-Red Bluff, CA

Year-round particle pollution

More than 20.3 million people live in one of the 21 counties where year-round particle pollution levels were worse than the national air quality limit.

Top 5 cities most polluted by year-round particle pollution:
Bakersfield, CA
Fresno-Madera-Hanford, CA
Visalia, CA
San Jose-San Francisco-Oakland, CA
Los Angeles-Long Beach, CA

Ozone pollution

Ground-level ozone pollution is a powerful respiratory irritant whose effects have been likened to a sunburn of the lung. Inhaling ozone can cause shortness of breath, trigger coughing and asthma attacks, and may shorten life. Warmer temperatures driven by climate change make ozone more likely to form and harder to clean up.

The report found that more than 122.3 million people live in a county earning a failing grade for ozone pollution. While this is 860,000 fewer than last year’s report, it includes millions of vulnerable people who are at an increased risk of harm from ozone, such as 27.8 million children and 18.5 million people ages 65 or older.

Top 5 cities most polluted by ozone pollution:
Los Angeles-Long Beach, CA
Bakersfield, CA
Visalia, CA
Fresno-Madera-Hanford, CA
Phoenix-Mesa, AZ

High marks

The report also recognizes the nation’s cleanest cities. To make the list, a city must experience no high ozone or particle pollution days and rank among the 25 cities with the lowest year-round particle pollution levels.

Cleanest U.S. cities (listed in alphabetical order):
Bangor, ME
Burlington-South Burlington-Barre, VT
Charlottesville, CA
Elmira-Corning, NY
Harrisonburg-Staunton, VA
Lincoln-Beatrice, NE
Roanoke, VA
Urban Honolulu, HI
Virginia Beach-Norfolk, VA-NC
Wilmington, NC