SmogRank / Countries / United States / Pennsylvania
Most polluted cities in Pennsylvania, United States
25 measured cities ranked by PM2.5, last 30 days. Worst: West Mifflin at 6.6 µg/m³, #1001 in the world.
| # | City | µg/m³ | |
|---|---|---|---|
| 1 | West Mifflin Pennsylvania | 6.6 | |
| 2 | Lancaster Pennsylvania | 6.5 | |
| 3 | Pittsburgh Pennsylvania | 6.5 | |
| 4 | Harrisburg Pennsylvania | 6.2 | |
| 5 | York Pennsylvania | 6.1 | |
| 6 | McKeesport Pennsylvania | 6.1 | |
| 7 | Wilkinsburg Pennsylvania | 6.0 | |
| 8 | Bensalem Pennsylvania | 5.9 | |
| 9 | Chambersburg Pennsylvania | 5.7 | |
| 10 | Philadelphia Pennsylvania | 5.7 | |
| 11 | Johnstown Pennsylvania | 5.7 | |
| 12 | Abington low-cost sensorsPennsylvania | 5.6 | |
| 13 | Upper Saint Clair Pennsylvania | 5.5 | |
| 14 | Lebanon Pennsylvania | 5.4 | |
| 15 | Scranton Pennsylvania | 5.3 | |
| 16 | Hermitage Pennsylvania | 5.1 | |
| 17 | State College Pennsylvania | 4.8 | |
| 18 | Erie Pennsylvania | 4.6 | |
| 19 | Allentown Pennsylvania | 4.5 | |
| 20 | Reading Pennsylvania | 4.5 | |
| 21 | Carlisle Pennsylvania | 4.4 | |
| 22 | Chester Pennsylvania | 4.3 | |
| 23 | Bethlehem Pennsylvania | 4.3 | |
| 24 | Norristown Pennsylvania | 4.0 | |
| 25 | Altoona Pennsylvania | 3.8 |
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.
| City | 7-day estimate |
|---|---|
| Levittown estimated | ≈ 4 µg/m³ |
| Havertown estimated | ≈ 5 µg/m³ |
| Wilkes-Barre estimated | ≈ 3 µg/m³ |
| Mount Lebanon estimated | ≈ 5 µg/m³ |
| Bethel Park estimated | ≈ 5 µg/m³ |
| Wayne estimated | ≈ 5 µg/m³ |
| Radnor estimated | ≈ 5 µg/m³ |
| Williamsport estimated | ≈ 3 µg/m³ |
| Monroeville estimated | ≈ 5 µg/m³ |
| Cranberry Township estimated | ≈ 4 µg/m³ |
| Drexel Hill estimated | ≈ 5 µg/m³ |
| Plum estimated | ≈ 5 µg/m³ |
| Back Mountain estimated | ≈ 3 µg/m³ |
| Easton estimated | ≈ 2 µg/m³ |
| Whitehall Township estimated | ≈ 2 µg/m³ |
| Hazleton estimated | ≈ 4 µg/m³ |
| Springfield estimated | ≈ 5 µg/m³ |
| Pottstown estimated | ≈ 3 µg/m³ |
| New Castle estimated | ≈ 3 µg/m³ |
| Allison Park estimated | ≈ 5 µg/m³ |
| Murrysville estimated | ≈ 5 µg/m³ |
| King of Prussia estimated | ≈ 4 µg/m³ |
| West Chester estimated | ≈ 3 µg/m³ |
| Baldwin estimated | ≈ 5 µg/m³ |
| Limerick estimated | ≈ 3 µg/m³ |
| Phoenixville estimated | ≈ 3 µg/m³ |
| Lansdale estimated | ≈ 3 µg/m³ |
| Willow Grove estimated | ≈ 5 µg/m³ |
| Hanover estimated | ≈ 4 µg/m³ |
Updated 2026-10-01 10:07 UTC. Values are PM2.5 in µg/m³ (fine particles), the median of each city's monitors.