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 29 Aug 2023: Açailândia 31.8 µg/m³, Rio Claro 23.0 µg/m³ and Ferraz de Vasconcelos 22.3 µg/m³.
- 1AçailândiaMaranhão31.8
- 2Rio ClaroSão Paulo23.0
- 3Ferraz de VasconcelosSão Paulo22.3
- 4CampinasSão Paulo20.2
- 5Ribeirão PretoSão Paulo20.0
- 6Santo AndréSão Paulo19.9
- 7São PauloSão Paulo19.6
- 8ItaquaquecetubaSão Paulo19.1
- 9LimeiraSão Paulo18.7
- 10TimóteoMinas Gerais18.6
- 11PaulíniaSão Paulo18.5
- 12JundiaíSão Paulo18.3
- 13São LuísMaranhão17.1
- 14PiracicabaSão Paulo16.7
- 15Coronel FabricianoMinas Gerais16.3
- 16Nova UniãoMinas Gerais16.1
- 17CongonhasMinas Gerais15.4
- 18Belo HorizonteMinas Gerais15.3
- 19GuaratinguetáSão Paulo15.2
- 20TaubatéSão Paulo14.8
+ 12 more cities, the next at 14.6 µg/m³
Not counted on this day, too few days measured: Brumadinho since 18 Aug 2023, Curitiba since 15 Aug 2023 and Araucária since 15 Aug 2023.
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.