SmogRank / World / United States / Missouri / December 2025
Most polluted cities in Missouri, United States, December 2025
10 cities in Missouri, United States ranked by their average PM2.5 over the 31 days. Worst: Columbia at 11.0 µg/m³, #1,125 of 2,960 cities in the world. Cleanest: Kearney at 5.9. A city needs measurements on 70% of the days to be ranked.
Ranked by unhealthy days: the share of each city's measured days with a daily mean over 35.4 µg/m³ (US AQI 101+), Unhealthy for Sensitive Groups or worse on the US EPA's scale. Ties go to the higher average.
- 1Columbialow-cost sensors 0%
- 2Lemay 0%
- 2Saint Joseph 0%
- 2St. Louis 0%
- 5University City 0%
- 6Kansas City 0%
- 7Arnold 0%
- 8Springfield 0%
- 9Raymore 0%
- 10Kearney 0%
Low-cost sensors: consumer units, counted only in cities with no government-grade monitor; they read close to reference monitors on the whole, but 15 to 25% high in humid air. How we use them.
The US EPA's Air Quality Index for PM2.5 (2024 breakpoints). Show values as: µg/m³ · US AQI · India AQI · China AQI · European AQI · UK DAQI · Canada AQHI+. About the scales
All cities in the world, December 2025 · All cities in United States, December 2025 · Missouri now
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SmogRank, most polluted cities in Missouri, United States, PM2.5, December 2025, smogrank.com/us/region/missouri/history/2025-12 (accessed 6 Oct 2026).
You're welcome to reuse a single chart, image or figure with this citation and a link. Terms. Raw monitor readings in bulk are published by OpenAQ, under each provider's licence.