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Philadelphians breathe some of the most polluted air in the country, according to a recent report from the American Lung Association.
The nonprofit’s annual State of the Air report ranked the Philadelphia-Reading-Camden statistical area — which covers parts of southeastern Pennsylvania, South Jersey, northern Delaware and northeast Maryland — the country’s 17th worst for average levels of particulate pollution between 2022 and 2024. That is down from 26th worst in last year’s report. Particulate pollution, sometimes called soot, comes from dust, fires, traffic and industry and can cause lung and heart issues.
“The more days that people are exposed to bad air, the more likely they are to experience asthma attacks, to need medication, to go to the hospital, end up in emergency rooms,” said Kevin Stewart, director of environmental health for the American Lung Association. “Sometimes, people even die from air pollution.”
The grim ranking was driven by pollution levels in Philadelphia, which had the dirtiest air out of the counties in the area.
During the three-year span covered by the report, average annual levels of particulate matter in Philadelphia exceeded the Environmental Protection Agency’s health-based standard. Philadelphia’s levels increased compared to last year’s report, putting the city “against the tide,” Stewart said.
“Generally, most of the places in the country did improve,” he said.
Smoke from wildfires in New Jersey and the western U.S. drove Philadelphia’s higher particulate levels in 2024, said Jim Garrow, spokesperson for the city’s Department of Public Health, but in general, Philadelphia’s air quality has improved over the last couple decades.
The American Lung Association also tracked daily spikes in particulate pollution and days in which ozone levels jumped above the EPA’s health-based threshold, and gave Philadelphia failing grades for both measures. Ground-level ozone forms when common pollutants from traffic and industry react, and can irritate airways and exacerbate asthma.
Some cities in South Jersey received better grades. Camden County earned “D”s for its high ozone days and daily spikes in particulate matter, but passed the EPA’s annual standard for particulate pollution. Gloucester County also passed on particulate pollution, but received a failing grade for ozone pollution, reflecting an average of over six unhealthy days per year.
The American Lung Association does not track why changes in air quality occur, but Stewart said worsening levels can reflect new sources of pollution, atmospheric conditions and weather.