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 Oct 2023: Açailândia 29.7 µg/m³, Rio Claro 18.1 µg/m³ and Campinas 17.0 µg/m³.
- 1AçailândiaMaranhão29.7
- 2Rio ClaroSão Paulo18.1
- 3CampinasSão Paulo17.0
- 4Ribeirão PretoSão Paulo16.9
- 5São LuísMaranhão16.6
- 6São PauloSão Paulo16.3
- 7PaulíniaSão Paulo16.3
- 8LimeiraSão Paulo16.2
- 9Santo AndréSão Paulo15.5
- 10Ferraz de VasconcelosSão Paulo15.4
- 11JundiaíSão Paulo14.7
- 12Nova UniãoMinas Gerais14.6
- 13PiracicabaSão Paulo14.5
- 14CongonhasMinas Gerais13.6
- 15Coronel FabricianoMinas Gerais13.0
- 16ItaquaquecetubaSão Paulo12.5
- 17TimóteoMinas Gerais11.8
- 18IpatingaMinas Gerais11.8
- 19São José dos CamposSão Paulo11.1
- 20ItabiraMinas Gerais10.6
+ 9 more cities, the next at 10.4 µg/m³
Not counted on this day, too few days measured: Ibirité since 14 Oct 2023, Conceição do Mato Dentro since 28 Sep 2023, Guaratinguetá since 24 Sep 2023 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.