SmogRank / World / Japan / Ibaraki / 2025

Most polluted cities in Ibaraki, Japan, 2025

19 cities in Ibaraki, Japan ranked by their average PM2.5 over the 365 days; 19 above the WHO annual guideline (5.0 µg/m³). Worst: Tsuchiura at 12.5 µg/m³, #569 of 2,624 cities in the world. Cleanest: Koga at 7.1. A city needs measurements on 70% of the days to be ranked.

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. Ties go to the higher average.

← Tsuchiura 2% 1.5%0
Every city in Ibaraki, Japan ranked for 2025, one column each, ranked by unhealthy days: height is the share of its measured days that were unhealthy, colour its average. Point at it to read a city; tap to open it.
  1. 1Tsuchiura
    2%
  2. 2Naka
    2%
  3. 3Shimo-tsuma
    2%
  4. 4Jōsō
    1%
  5. 5Mito
    1%
  6. 6Kamisu
    1%
  7. 7Toride
    1%
  8. 8Chikusei
    1%
  9. 9Inashiki
    1%
  10. 10Kashima-shi
    1%
  11. 11Hokota
    1%
  12. 12Kasama
    1%
  13. 13Ishioka
    1%
  14. 14Bandō
    1%
  15. 15Hitachi-Naka
    0%
  16. 16Hitachi
    0%
  17. 17Hitachiomiya
    0%
  18. 18Kitaibaraki
    0%
  19. 19Koga
    0%
Good0–50
Moderate51–100
Sensitive groups101–150
Unhealthy151–200
Very unhealthy201–300
Hazardous301+

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

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SmogRank, most polluted cities in Ibaraki, Japan, PM2.5, 2025, smogrank.com/jp/region/ibaraki/history/2025 (accessed 6 Oct 2026).

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