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 18 Aug 2025: Rio Claro 22.8 µg/m³, Nova União 22.0 µg/m³ and Jundiaí 19.9 µg/m³.
- 1Rio ClaroSão Paulo22.8
- 2Nova UniãoMinas Gerais22.0
- 3JundiaíSão Paulo19.9
- 4ItaquaquecetubaSão Paulo18.6
- 5Ribeirão PretoSão Paulo18.5
- 6Ferraz de VasconcelosSão Paulo18.5
- 7São José do Rio PretoSão Paulo18.3
- 8Foz do IguaçuParaná17.9
- 9São PauloSão Paulo17.8
- 10LimeiraSão Paulo17.7
- 11AraucáriaParaná17.4
- 12PaulíniaSão Paulo17.1
- 13TimóteoMinas Gerais16.8
- 14BetimMinas Gerais16.6
- 15PiracicabaSão Paulo16.4
- 16Coronel FabricianoMinas Gerais16.4
- 17GuarapuavaParaná16.3
- 18ItabiraMinas Gerais16.2
- 19GuaratinguetáSão Paulo16.0
- 20Três LagoasMato Grosso do Sul15.6
+ 26 more cities, the next at 14.4 µg/m³
Not counted on this day, too few days measured: Colombo since 16 Aug 2025, Paranaguá since 10 Aug 2025, Santo André since 31 Jul 2025 and Portalegre since 25 Jul 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.