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 21 Mar 2025: Nova União 15.6 µg/m³, Guarapuava 14.9 µg/m³ and Rio Claro 13.5 µg/m³.
- 1Nova UniãoMinas Gerais15.6
- 2GuarapuavaParaná14.9
- 3Rio ClaroSão Paulo13.5
- 4Santo AndréSão Paulo13.3
- 5São LuísMaranhão13.2
- 6Ferraz de VasconcelosSão Paulo12.4
- 7Coronel FabricianoMinas Gerais12.4
- 8São PauloSão Paulo12.1
- 9ColomboParaná12.0
- 10ItaquaquecetubaSão Paulo11.5
- 11TimóteoMinas Gerais11.3
- 12JundiaíSão Paulo11.1
- 13Ribeirão PretoSão Paulo10.8
- 14MaringáParaná10.8
- 15SantosSão Paulo10.3
- 16ItabiraMinas Gerais10.0
- 17CampinasSão Paulo10.0
- 18AraucáriaParaná10.0
- 19São José do Rio PretoSão Paulo9.7
- 20Ponta GrossaParaná9.4
+ 25 more cities, the next at 9.4 µg/m³
Not counted on this day, too few days measured: Cubatão since 21 Mar 2025, Foz do Iguaçu since 15 Mar 2025, Francisco Beltrão since 12 Mar 2025 and Limeira since 4 Mar 2025.
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, Turkey and Iran, which publish only on their own websites. We are building the reader for China's network. The networks of Turkey and Iran don't answer requests from outside their countries, so we can't read them. Most cities there are missing from this board, not clean. Why.