US Cities with Worst Air Quality Overall

Cities with the most polluted air based on 2025 EPA monitoring data. These communities face the greatest health risks from air pollution.

Health Impact

40.9M
People in highly polluted areas
8
Avg unhealthy days per city
2122
Highest AQI recorded
Showing 1–8 of 8 cities
  1. #1

    Detroit, MI

    Population: 3,773,725Monitored: 304 days
    B
    Median: 52
    Good:141
    Moderate:153
    Sensitive:7
    Unhealthy:3
    Very Unhealthy:
    Hazardous:
  2. #2

    Grand Rapids, MI

    Population: 622,168Monitored: 304 days
    B+
    Median: 46
    Good:182
    Moderate:118
    Sensitive:4
    Unhealthy:
    Very Unhealthy:
    Hazardous:
  3. #3

    South Lyon, MI

    Population: 146,383Monitored: 304 days
    A-
    Median: 41
    Good:228
    Moderate:70
    Sensitive:5
    Unhealthy:1
    Very Unhealthy:
    Hazardous:
  4. #4

    Warren, MI

    Population: 137,928Monitored: 303 days
    A-
    Median: 41
    Good:224
    Moderate:73
    Sensitive:5
    Unhealthy:1
    Very Unhealthy:
    Hazardous:
  5. #5

    Holland, MI

    Population: 107,348Monitored: 302 days
    A
    Median: 40
    Good:235
    Moderate:63
    Sensitive:4
    Unhealthy:
    Very Unhealthy:
    Hazardous:
  6. #6

    Kalamazoo, MI

    Population: 215,288Monitored: 304 days
    A
    Median: 40
    Good:225
    Moderate:75
    Sensitive:4
    Unhealthy:
    Very Unhealthy:
    Hazardous:
  7. #7

    Flint, MI

    Population: 295,285Monitored: 303 days
    A
    Median: 38
    Good:252
    Moderate:48
    Sensitive:3
    Unhealthy:
    Very Unhealthy:
    Hazardous:
  8. #8

    Lansing, MI

    Population: 328,527Monitored: 304 days
    A
    Median: 37
    Good:252
    Moderate:49
    Sensitive:3
    Unhealthy:
    Very Unhealthy:
    Hazardous:

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