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.
The worst cities in Brazil for PM2.5 over the 30 days to 2 Oct 2026: Rio Claro 14.5 µg/m³, Nilópolis 14.2 µg/m³ and São José do Rio Preto 12.4 µg/m³.
- 1Rio ClaroSão Paulo14.5
- 2NilópolisRio de Janeiro14.2
- 3São José do Rio PretoSão Paulo12.4
- 4São PauloSão Paulo11.0
- 5Ribeirão PretoSão Paulo11.0
- 6LimeiraSão Paulo11.0
- 7ItaquaquecetubaSão Paulo10.8
- 8Santo AndréSão Paulo10.4
- 9Ferraz de VasconcelosSão Paulo10.0
- 10PaulíniaSão Paulo9.8
- 11JundiaíSão Paulo9.6
- 12CampinasSão Paulo9.5
- 13BauruSão Paulo9.4
- 14Duque de CaxiasRio de Janeiro9.0
- 15SorocabaSão Paulo8.9
- 16PiracicabaSão Paulo8.8
- 17ItaguaíRio de Janeiro8.2
- 18GuaratinguetáSão Paulo8.1
- 19CubatãoSão Paulo8.1
- 20São José dos CamposSão Paulo8.0
+ 6 more cities, the next at 7.4 µg/m³
Cities counted each 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.