SmogRank / Countries / United States / Pennsylvania

Most polluted cities in Pennsylvania, United States

23 measured cities ranked by PM2.5, this year. Worst: Philadelphia at 11.2 µg/m³, #475 in the world.

#City µg/m³× WHO
1Philadelphia Pennsylvania
11.22.2×
2York Pennsylvania
11.22.2×
3Lancaster Pennsylvania
10.62.1×
4Lebanon Pennsylvania
9.92.0×
5West Mifflin Pennsylvania
9.92.0×
6Harrisburg Pennsylvania
9.71.9×
7Bensalem Pennsylvania
9.31.9×
8Carlisle Pennsylvania
9.11.8×
9Pittsburgh Pennsylvania
9.11.8×
10Reading Pennsylvania
9.11.8×
11Wilkinsburg Pennsylvania
8.91.8×
12Chester Pennsylvania
8.41.7×
13Norristown Pennsylvania
8.41.7×
14Johnstown Pennsylvania
8.31.7×
15Bethlehem Pennsylvania
8.21.6×
16McKeesport Pennsylvania
8.11.6×
17State College Pennsylvania
8.11.6×
18Hermitage Pennsylvania
7.91.6×
19Scranton Pennsylvania
7.81.6×
20Upper Saint Clair Pennsylvania
7.81.6×
21Allentown Pennsylvania
7.71.5×
22Erie Pennsylvania
7.71.5×
23Altoona Pennsylvania
7.41.5×
Good 0–9.0Moderate 9.1+Unhealthy for sensitive groups 35.5+Unhealthy 55.5+Very unhealthy 125.5+Hazardous 225.5+No data

Estimated: cities without a monitor

Pennsylvania cities we can't measure, with model estimates for the last 7 days. Listed by population, not ranked: estimates aren't precise enough to rank. Model estimates from the Copernicus Atmosphere Monitoring Service (CAMS), adjusted to measured cities nearby where there are any. Adjusted, a single day lands within ×1.5 of what a monitor would read about two times in three; unadjusted, it can be off by half or double. Treat them as a guide, not a measurement.

City7-day estimateBand
Levittown estimated≈ 4 µg/m³Good
Havertown estimated≈ 5 µg/m³Good
Wilkes-Barre estimated≈ 3 µg/m³Good
Mount Lebanon estimated≈ 5 µg/m³Good
Bethel Park estimated≈ 5 µg/m³Good
Wayne estimated≈ 5 µg/m³Good
Radnor estimated≈ 5 µg/m³Good
Williamsport estimated≈ 3 µg/m³Good
Monroeville estimated≈ 5 µg/m³Good
Cranberry Township estimated≈ 4 µg/m³Good
Drexel Hill estimated≈ 5 µg/m³Good
Plum estimated≈ 5 µg/m³Good
Back Mountain estimated≈ 3 µg/m³Good
Easton estimated≈ 2 µg/m³Good
Whitehall Township estimated≈ 2 µg/m³Good
Hazleton estimated≈ 4 µg/m³Good
Springfield estimated≈ 5 µg/m³Good
Pottstown estimated≈ 3 µg/m³Good
New Castle estimated≈ 3 µg/m³Good
Allison Park estimated≈ 5 µg/m³Good
Murrysville estimated≈ 5 µg/m³Good
King of Prussia estimated≈ 4 µg/m³Good
West Chester estimated≈ 3 µg/m³Good
Baldwin estimated≈ 5 µg/m³Good
Limerick estimated≈ 3 µg/m³Good
Phoenixville estimated≈ 3 µg/m³Good
Lansdale estimated≈ 3 µg/m³Good
Willow Grove estimated≈ 5 µg/m³Good
Hanover estimated≈ 4 µg/m³Good

Updated 2026-10-01 07:07 UTC. Values are PM2.5 in µg/m³ (fine particles), the median of each city's monitors.