SmogRank / History / City race

Cities in Brazil, worst air first, day by day

Each measured city's average over the 30 days to every day since January 2023, worst first. Find your own city to follow it through the race, or keep to one country.

CountriesCities
The 30 days to17 Dec 2023 That day's board

The worst cities in Brazil for PM2.5 over the 30 days to 17 Dec 2023: Açailândia 21.6 µg/m³, Santos 14.2 µg/m³ and Conceição do Mato Dentro 13.6 µg/m³.

  1. 1AçailândiaMaranhão21.6
  2. 2SantosSão Paulo14.2
  3. 3Conceição do Mato DentroMinas Gerais13.6
  4. 4Santo AndréSão Paulo13.4
  5. 5São PauloSão Paulo13.3
  6. 6TimóteoMinas Gerais13.0
  7. 7São LuísMaranhão12.7
  8. 8SerraEspírito Santo12.7
  9. 9CampinasSão Paulo12.7
  10. 10Rio ClaroSão Paulo12.6
  11. 11LimeiraSão Paulo12.6
  12. 12Coronel FabricianoMinas Gerais12.6
  13. 13Ferraz de VasconcelosSão Paulo12.5
  14. 14IpatingaMinas Gerais12.2
  15. 15CongonhasMinas Gerais12.1
  16. 16ItaquaquecetubaSão Paulo11.6
  17. 17JundiaíSão Paulo11.3
  18. 18PaulíniaSão Paulo11.2
  19. 19ItabiraMinas Gerais11.2
  20. 20AraucáriaParaná11.1

+ 13 more cities, the next at 10.6 µg/m³

Not counted on this day, too few days measured: Betim since 16 Dec 2023, Belo Horizonte since 1 Dec 2023, Ibirité since 1 Nov 2023 and 2 more cities.

30 days7 days
GoodModerateSensitive groupsUnhealthyVery unhealthyHazardousWHO 24-hour guideline, 15 µg/m³Fades where it stood: not counted that day

A city's number is its average over the 30 days, shown only when 21 of them were measured (5 of 7 on the 7-day race), the same minimum as the 30- and 7-day boards. A city whose monitors go quiet fades out where it stood rather than sliding down, so a gap never reads as cleaner air. Some large countries are thin or missing because their monitors' licences don't allow reuse. How we rank.

Not covered: the government monitoring networks of China and Turkey, which publish only on their own websites. We are building the reader for China's network. Turkey's network doesn't answer requests from outside the country, so we can't read it. Most cities there are missing from this board, not clean. Why.