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 10 Apr 2025: Nova União 19.4 µg/m³, Foz do Iguaçu 14.7 µg/m³ and Rio Claro 13.4 µg/m³.
- 1Nova UniãoMinas Gerais19.4
- 2Foz do IguaçuParaná14.7
- 3Rio ClaroSão Paulo13.4
- 4Coronel FabricianoMinas Gerais12.8
- 5Ferraz de VasconcelosSão Paulo11.8
- 6TimóteoMinas Gerais11.3
- 7São PauloSão Paulo11.2
- 8Belo HorizonteMinas Gerais11.1
- 9Santo AndréSão Paulo10.8
- 10SantosSão Paulo10.6
- 11ItabiraMinas Gerais10.5
- 12ItaquaquecetubaSão Paulo10.4
- 13JundiaíSão Paulo10.2
- 14São LuísMaranhão10.1
- 15IbiritéMinas Gerais10.1
- 16AraucáriaParaná10.1
- 17LimeiraSão Paulo9.9
- 18MaringáParaná9.7
- 19PiracicabaSão Paulo9.3
- 20BauruSão Paulo9.2
+ 22 more cities, the next at 9.1 µg/m³
Not counted on this day, too few days measured: União da Vitória since 5 Apr 2025, Guarapuava since 3 Apr 2025, Paranaguá since 2 Apr 2025 and 3 more cities.
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.