SmogRank / World / Japan / Hiroshima / October 2026
Most polluted cities in Hiroshima, Japan, October 2026
10 cities in Hiroshima, Japan ranked by their average PM2.5 so far (5 of 31 days). Worst: Fukuyama at 9.5 µg/m³, #544 of 2,246 cities in the world. Cleanest: Miyoshi at 5.7. A city needs measurements on 70% of the days to be ranked.
About 0 people in these 3 cities breathed unhealthy air on an average day of October 2026.
Ranked by people: each city's population times its share of unhealthy days, those with a daily mean over 35.4 µg/m³ (US AQI 101+). That is how many people living there breathed unhealthy air on an average day. Only cities measured at 2 or more places at least 3 km apart are ranked: one monitor shouldn't speak for a whole city. Population is the city itself, not its wider metro area.
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, October 2026 · All cities in Japan, October 2026 · Hiroshima now
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SmogRank, most polluted cities in Hiroshima, Japan, PM2.5, October 2026 (so far), smogrank.com/jp/region/hiroshima/history/2026-10 (accessed 6 Oct 2026).
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.