The Pittsburgh region’s air is among the most polluted in the country, according to a study by the American Lung Association.
The Pittsburgh-Weirton-Steubenville metro area ranked 16th worst in the nation for daily particle pollution and 12th worst for year-round particle pollution, the report found.
Kevin Stewart, director of environmental health with the American Lung Association and resident of Lancaster, said particle pollution is a complex mixture of tiny pieces of solids and sometimes liquids that are suspended in the air.
Ozone and particle pollution can cause various health effects, like asthma attacks, heart attacks, strokes, preterm births, impaired cognitive functioning and lung cancer.
“Children, senior citizens, people with chronic lung disease and chronic heart disease, individuals who are living in poverty, people of color, people who are pregnant … are at higher risk for health for exposure,” he said, especially people with cardiovascular disease.
Through the American Lung Association’s “State of the Air” report, exposure to unhealthy levels of ground-level ozone air pollution — smog — is graded, as well as year-‘round and short-term spikes in particle pollution — soot — over a three-year period.
This report looks at the air quality data from 2021-2023.
For the year-‘round average level of particle pollution, the area’s worst county — Allegheny County — received a failing grade for pollution levels above the federal standard, according to the report.
The federal standard for the nation is 9 micrograms per cubic meter, which is a year-‘round measure of the fine particles in the air, according to the U.S. Environmental Protection Agency, Stewart said. It’s based on the three-year reporting period of 2021-2023.
The average level in Allegheny County this year was 11.6 micrograms per cubic meter, which is a higher number compared to last year’s measurement of 10.9 micrograms per cubic meter, according to Stewart.
The American Lung Association said though the Pittsburgh area is back on the list of the 25 most polluted cities, the 2023 wildfire smoke from the west contributed to poorer air quality.
Stewart said the association recognizes Allegheny County’s “history of legacy industries” like steel, which contribute to air pollution levels.
“We have advocated along with many other groups that those air pollution sources do need to be better controlled so that the people who live in the vicinity of those aren’t exposed to levels that are clearly unhealthy,” he said.
The Pittsburgh-Weirton-Steubenville metro area also ranked 90th worst in the nation for ozone pollution, which was based on the area’s worst county’s average number of unhealthy days.
It was Allegheny County, with an average of 2.5 unhealthy days per year — a D grade, the report said. However, it was better than last year’s report, which was 50th worst, with 2.7 days per year and a D grade.
Unhealthy days are denoted by the EPA, according to Stewart, and the measurement is calculated compared to the standard. The only way to get an A grade is to have zero bad air days over the three-year tracking period. None of the 13 counties in the Pittsburgh-Weirton-Steubenville areas received an A grade.
“Even one bad air day can be one bad air day too many,” Stewart said.
The Pittsburgh-Weirton-Steubenville metro area ranked the worst in the Mid-Atlantic region, which includes Delaware, Maryland, the District of Columbia, New Jersey, Pennsylvania, Virginia and West Virginia, for both daily and year-‘round particle pollution, according to the report.
For short-term spikes in particle pollution, which the American Lung Association said can be extremely dangerous and even deadly, the Pittsburgh-Weirton-Steubenville metro area ranked 16th worst in the nation.
It was based on the area’s worst county’s average number of unhealthy days — 10.8 days per year, an F grade, in Allegheny County. This was worse than last year’s report of 26th worst, with seven days per year and an F grade, the report said.
The air pollutants highlighted in the 2025 “State of the Air” report are widespread and pose a risk to everyone’s health, according to Elizabeth Hensil, director of advocacy in Pennsylvania at the American Lung Association.
“Both ozone and particle pollution can lead to premature death and cause serious health issues such as asthma attacks, heart attacks, strokes, preterm births and even problems with cognitive function later in life,” she said. “Particle pollution can also increase the risk of lung cancer.”
Hensil urged Pennsylvania policymakers to take action to improve air quality in the Pittsburgh metro area.
“Sadly, too many people in the metro area are living with dangerous levels of ozone and particle pollution,” she said. “This pollution is making kids have asthma attacks, causing people to work outdoors to get sick and (be) unable to work.”
Other findings across Pennsylvania, according to the report, include:
• Philadelphia-Reading-Camden — ranked third worst in Mid-Atlantic for both ozone smog and daily particle pollution, as well as 26th worst in country for year-round particle levels (second worst in the Mid-Atlantic).
• Altoona-Huntingdon — daily measure for fine particle pollution worsens in the metro area from 124th worst to 58th worst in country as grade drops from B to F.
• Johnstown-Somerset metro area — daily measure for particle pollution worsens from 124th worst in country to 104th worst, going from B to C grade, but year-‘round levels improved from 42nd worst to 83rd worst and the grade moved from failing to passing.
Overall, the report found that 156 million people in the United States, or 46%, live in an area that received a failing grade for at least one measure of air pollution, and 42.5 million people live in areas with failing grades for all three measures.
The “State of the Air” report also discovered that a person of color in the United States is more than twice as likely as a white person to live in a community with a failing grade on all three pollution measures. And Hispanic residents are nearly three times as likely as white residents to live in a community with three failing grades.
This has to do with the nationwide averages, Stewart said, as more Hispanic people live in California, for example, and that state has a lot worse air quality. And adults of color are more likely to be experiencing cardiovascular disease or lung health overall, according to Stewart.
“The rates of those diseases tend to be higher in those groups, and that also puts them at risk,” he said. “Asthma (is) more likely in kids of low income populations people of color as well. Asthma puts you at greater risk of having a problem of air pollution.”
Pittsburgh area residents can take steps to decrease their air pollution like maintaining cars and heating systems, as well as avoiding trash, leaf and wood burning, according to Stewart.
“Everybody together does contribute to air pollution,” he said. “We’re certainly hoping that the air quality improves.”
Megan Swift is a TribLive reporter covering trending news in Western Pennsylvania. A Murrysville native, she joined the Trib full time in 2023 after serving as editor-in-chief of The Daily Collegian at Penn State. She previously worked as a Jim Borden Scholarship intern at the Trib for three summers. She can be reached at mswift@triblive.com.
