SmogRank / World / Brazil / Paraná / January 2023

Most unhealthy days in Paraná, Brazil, January 2023

1 city in Paraná, Brazil ranked by its share of unhealthy days over the 31 days. The most unhealthy days: Curitiba, Brazil, 0 of 28 measured days. A city needs measurements on 70% of the days to be ranked.

OpenAQ's archive, where our readings come from, has almost none for 7 of these 31 days. Cities in the United States and Europe have them from the EPA's and the European Environment Agency's own records of the same monitors; elsewhere a city's average is over its other days. Why.

Ranked by unhealthy days: the share of each city's measured days with a daily mean over 35.4 µg/m³ (US AQI 101+), Unhealthy for Sensitive Groups or worse on the US EPA's scale. Cities with the same share are ordered by more unhealthy days, then by the higher average.

The US EPA's Air Quality Index for PM2.5 (2024 breakpoints). Show values as: µg/m³ · US AQI · India AQI · China AQI · European AQI · UK DAQI · Canada AQHI+. About the scales

All cities in the world, January 2023 · All cities in Brazil, January 2023 · Paraná now

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SmogRank, most polluted cities in Paraná, Brazil by unhealthy days (PM2.5), January 2023: each city's share of its measured days with a daily mean over 35.4 µg/m³, cities measured on 22 or more of the 31 days. Monitor data from national networks via OpenAQ and the publishers listed at smogrank.com/sources. smogrank.com/br/region/parana/history/2023-01?by=days (accessed 12 Oct 2026).

Download top 10 by average (PNG)

You're welcome to reuse a single chart, image or figure with this citation and a link. Terms. Raw monitor readings in bulk are published by OpenAQ, under each provider's licence.