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 1–5 of 5 cities
  1. #1

    Waterloo, IA

    Population: 119,632Monitored: 304 days
    B+
    Median: 48
    Good:172
    Moderate:130
    Sensitive:1
    Unhealthy:1
    Very Unhealthy:
    Hazardous:
  2. #2

    Des Moines, IA

    Population: 570,091Monitored: 304 days
    B+
    Median: 46
    Good:178
    Moderate:124
    Sensitive:2
    Unhealthy:
    Very Unhealthy:
    Hazardous:
  3. #3

    Davenport, IA

    Population: 281,044Monitored: 305 days
    A-
    Median: 45
    Good:182
    Moderate:121
    Sensitive:1
    Unhealthy:1
    Very Unhealthy:
    Hazardous:
  4. #4

    Cedar Rapids, IA

    Population: 195,323Monitored: 304 days
    A-
    Median: 44
    Good:186
    Moderate:113
    Sensitive:4
    Unhealthy:1
    Very Unhealthy:
    Hazardous:
  5. #5

    Iowa City, IA

    Population: 133,565Monitored: 304 days
    A
    Median: 36
    Good:216
    Moderate:84
    Sensitive:3
    Unhealthy:1
    Very Unhealthy:
    Hazardous:

Protect Your Health from Air Pollution

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