SmogRank / Countries / United States / Massachusetts

Most polluted cities in Massachusetts, United States

15 measured cities, last 30 days; 0 above the WHO 24-hour guideline. Worst: Brockton at 4.7 µg/m³, #1,901 in the world.

15 good

  1. 1Brockton 4.7
  2. 2Springfield 4.6
  3. 3Boston 4.3
  4. 4Fall River 4.2
  5. 5Quincy 4.2
  6. 6Lowell 4.1
  7. 7Greenfield 3.9
  8. 8Lynn 3.9
  9. 9Milford 3.9
  10. 10Pittsfield 3.8
  11. 11Framingham 3.6
  12. 12Haverhill 3.6
  13. 13Worcester 3.6
  14. 14North Chicopee 3.3
  15. 15Lexingtonlow-cost sensors 1.6
Good0–9.0
Moderate9.1–35.4
Sensitive groups35.5–55.4
Unhealthy55.5–125.4
Very unhealthy125.5–225.4
Hazardous225.5+

Estimated: cities without a monitor

Massachusetts 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
Cambridge≈ 4 µg/m³Good
New Bedford≈ 4 µg/m³Good
Dorchester≈ 4 µg/m³Good
Somerville≈ 4 µg/m³Good
Lawrence≈ 3 µg/m³Good
Framingham Center≈ 3 µg/m³Good
Waltham≈ 4 µg/m³Good
Malden≈ 4 µg/m³Good
Brookline≈ 4 µg/m³Good
Medford≈ 4 µg/m³Good
Taunton≈ 4 µg/m³Good
Chicopee≈ 3 µg/m³Good
Weymouth≈ 5 µg/m³Good
Revere≈ 4 µg/m³Good
Peabody≈ 5 µg/m³Good
Methuen≈ 3 µg/m³Good
South Peabody≈ 5 µg/m³Good
Barnstable≈ 4 µg/m³Good
Everett≈ 4 µg/m³Good
Brighton≈ 4 µg/m³Good
Attleboro≈ 4 µg/m³Good
East Boston≈ 4 µg/m³Good
Salem≈ 5 µg/m³Good
Arlington≈ 4 µg/m³Good
Westfield≈ 3 µg/m³Good
Leominster≈ 3 µg/m³Good
Beverly≈ 5 µg/m³Good
Holyoke≈ 2 µg/m³Good
Fitchburg≈ 2 µg/m³Good
Beverly Cove≈ 5 µg/m³Good
Billerica≈ 4 µg/m³Good
Amherst≈ 2 µg/m³Good
Marlborough≈ 3 µg/m³Good
Woburn≈ 4 µg/m³Good
Chelsea≈ 4 µg/m³Good
Braintree≈ 4 µg/m³Good
Mattapan≈ 4 µg/m³Good
Chelmsford≈ 4 µg/m³Good
Shrewsbury≈ 3 µg/m³Good
Natick≈ 4 µg/m³Good

Updated 2026-10-01 20:07 UTC. Values are PM2.5 in µg/m³ (fine particles), the median of each city's monitors.