SmogRank / World / Mexico / March 2023

Most polluted cities in Mexico, March 2023

2 cities in Mexico ranked by their average PM2.5 over the 31 days. Worst: Heroica Matamoros at 10.8 µg/m³, #200 of 867 cities in the world. Cleanest: Nogales at 8.5. A city needs measurements on 70% of the days to be ranked.

OpenAQ's archive, where our readings come from, has almost none for 20 of these 31 days. Cities in the United States and Europe have them from the EPA's and the European Environment Agency's own records of the same monitors; many cities elsewhere are missing from this board, not clean. Why.

Mexico has 43 cities ranked over the last 30 days, but only 2 here: most of its monitors have no readings for March 2023 in OpenAQ's archive, where ours come from, or too few to rank. Cities missing from this board weren't clean, just not measured.

  1. 1Heroica MatamorosTamaulipas
    54
  2. 2NogalesSonora
    47
Good0–50
Moderate51–100
Sensitive groups101–150
Unhealthy151–200
Very unhealthy201–300
Hazardous301+

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, March 2023 · Mexico now

Regions

Sonora 1Tamaulipas 1

Ranked cities in each region, March 2023.

Use this board

SmogRank, most polluted cities in Mexico, PM2.5, March 2023, smogrank.com/mx/history/2023-03 (accessed 6 Oct 2026).

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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.