SmogRank / World / Mexico / 2023

Most polluted cities in Mexico, 2023

10 cities in Mexico ranked by their average PM2.5 over the 365 days; 10 above the WHO annual guideline (5.0 µg/m³). Worst: Celaya at 24.2 µg/m³, #52 of 1,302 cities in the world. Cleanest: Nogales at 10.6. A city needs measurements on 70% of the days to be ranked.

OpenAQ's archive, where our readings come from, has almost none for 56 of these 365 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; elsewhere a city's average is over its other days. Why.

Mexico has 43 cities ranked over the last 30 days, but only 10 here: most of its monitors have no readings for 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.

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.

← Celaya 16% 10%0
Every city in Mexico ranked for 2023, one column each, ranked by unhealthy days: height is the share of its measured days that were unhealthy, colour its average. Point at it to read a city; tap to open it.
  1. 1CelayaGuanajuato
    16%
  2. 2TijuanaBaja California
    9%
  3. 3SalamancaGuanajuato
    4%
  4. 4IrapuatoGuanajuato
    3%
  5. 5Ciudad JuárezChihuahua
    3%
  6. 6León de los AldamaGuanajuato
    3%
  7. 7NogalesSonora
    1%
  8. 8GuanajuatoGuanajuato
    1%
  9. 9AbasoloGuanajuato
    1%
  10. 10San Luis de la PazGuanajuato
    0%
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, 2023 · Mexico now

Regions

Baja California 1Chihuahua 1Guanajuato 7Sonora 1

Ranked cities in each region, 2023.

Use this board

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

Download top 10 (PNG)

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.