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 28 Oct 2023: Açailândia 28.9 µg/m³, São Luís 16.0 µg/m³ and Rio Claro 15.0 µg/m³.
- 1AçailândiaMaranhão28.9
- 2São LuísMaranhão16.0
- 3Rio ClaroSão Paulo15.0
- 4Ribeirão PretoSão Paulo14.3
- 5LimeiraSão Paulo14.2
- 6CampinasSão Paulo14.1
- 7PaulíniaSão Paulo13.4
- 8Nova UniãoMinas Gerais12.9
- 9São PauloSão Paulo12.9
- 10Coronel FabricianoMinas Gerais12.3
- 11PiracicabaSão Paulo11.9
- 12JundiaíSão Paulo11.7
- 13IpatingaMinas Gerais11.7
- 14TimóteoMinas Gerais11.2
- 15CongonhasMinas Gerais11.2
- 16Santo AndréSão Paulo11.1
- 17Ferraz de VasconcelosSão Paulo11.0
- 18ItaquaquecetubaSão Paulo10.6
- 19ItabiraMinas Gerais9.3
- 20São José dos CamposSão Paulo8.0
+ 6 more cities, the next at 8.0 µg/m³
Not counted on this day, too few days measured: Canaã dos Carajás since 23 Oct 2023, Taubaté since 20 Oct 2023, Duque de Caxias since 19 Oct 2023 and 6 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, 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.