SmogRank / World / North America

Most polluted cities in North America

11 of 826 measured cities in 6 countries were above the WHO 24-hour guideline over the last 30 days. The worst was Tuxtla, Mexico, at 28.4 µg/m³.

VenezuelaU.S. Virgin IslandsPuerto Rico: 1 measured cityUnited States: 688 measured citiesAnguillaCayman IslandsBermudaBritish Virgin IslandsTurks and Caicos IslandsTrinidad and TobagoSurinameSaint Vincent and the GrenadinesSaint LuciaSaint Kitts and NevisRussiaPanamaNicaraguaArubaCuracaoMexico: 40 measured citiesJamaicaHonduras: 1 measured cityHaitiGuyanaGuatemalaGrenadaFrance: 102 measured citiesSaint Pierre and MiquelonSaint Martin: 1 measured cityEl SalvadorDominican RepublicDominicaGreenlandCubaCosta RicaColombiaCanada: 95 measured citiesBrazil: 6 measured citiesBelizeBarbadosBahamasAntigua and BarbudaSint Maarten
Each dot is a measured city, coloured by its PM2.5 over the last 30 days; tap a country to open it.
← Tuxtla 28.4 µg/m³ 15 µg/m³ WHO 24-hour guideline0
Every measured city in North America, one column each, worst on the left and cleanest on the right; height is PM2.5 in µg/m³. Point at it to read a city; tap to open it.

Countries

CountryCitiesMedianCities by bandWorst city
Honduras113.2 San Pedro Sula 13.2
Mexico4012.5 Tuxtla 28.4
Puerto Rico110.3 Cataño 10.3
Saint Martin19.1 Marigot 9.1
United States6885.7 Calexico 23.1
Canada955.0 Kamloops 8.1

Worst cities

  1. 1TuxtlaChiapas, Mexico 47
  2. 2Hacienda Santa FeJalisco, Mexico 40
  3. 3CalexicoCalifornia, United States 38
  4. 4San Salvador TizatlalliMéxico, Mexico 32
  5. 5Ciudad NezahualcoyotlMéxico, Mexico 30
  6. 6Naucalpan de JuárezMéxico, Mexico 30
  7. 7Santa AnitaJalisco, Mexico 30
  8. 8AguascalientesAguascalientes, Mexico 30
  9. 9SaltilloCoahuila, Mexico 28
  10. 10GuadalajaraJalisco, Mexico 28
  11. 11PueblaPuebla, Mexico 25
  12. 12Mexico CityMexico City, Mexico 25
  13. 13TlaquepaqueJalisco, Mexico 25
  14. 14Ciudad General EscobedoNuevo León, Mexico 25
  15. 15Parque Industrial Ciudad MitrasNuevo León, Mexico 25
  16. 16SalamancaGuanajuato, Mexico 23
  17. 17CelayaGuanajuato, Mexico 23
  18. 18León de los AldamaGuanajuato, Mexico 22
  19. 19San Pedro Sulalow-cost sensorsCortés Department, Honduras 22
  20. 20Jurupa ValleyCalifornia, United States 22
  21. 21TijuanaBaja California, Mexico 22
  22. 22IrapuatoGuanajuato, Mexico 22
  23. 23MonterreyNuevo León, Mexico 22
  24. 24Santa CatarinaNuevo León, Mexico 20
  25. 25RiversideCalifornia, United States 20
All cities in the world
Good0–50
Satisfactory51–100
Moderate101–200
Poor201–300
Very poor301–400
Severe401+

India's National Air Quality Index (CPCB), PM2.5 sub-index. Show values as: µg/m³ · US AQI · India AQI · China AQI · European AQI · UK DAQI · Canada AQHI+. About the scales

Updated 2026-10-02 07:07 UTC. Values are PM2.5 (fine particles), the median of each city's monitors, as the India AQI PM2.5 sub-index.