SmogRank / World / Chile / Biobio / June 2025

Most unhealthy days in Biobio, Chile, June 2025

13 cities in Biobio, Chile ranked by their share of unhealthy days over the 30 days. The most unhealthy days: Nacimiento, Chile, 30 of 30 measured days. 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.

← Nacimiento 100% 75%0
Every city in Biobio, Chile ranked for June 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. 1Nacimiento
    30 of 30
  2. 2Laja
    29 of 30
  3. 3Hualpén
    28 of 29
  4. 4Curanilahue
    25 of 28
  5. 5Hualqui
    23 of 27
  6. 6Coronel
    24 of 30
  7. 7Los Ángeles
    23 of 30
  8. 8Talcahuano
    23 of 30
  9. 9Concepción
    15 of 27
  10. 10Chiguayante
    15 of 30
  11. 11Tomé
    11 of 24
  12. 12San Pedro de la Paz
    12 of 30
  13. 13Lota
    0 of 26
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

All cities in the world, June 2025 · All cities in Chile, June 2025 · Biobio now

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SmogRank, most polluted cities in Biobio, Chile, by unhealthy days, PM2.5, June 2025, smogrank.com/cl/region/biobio/history/2025-06?by=days (accessed 7 Oct 2026).

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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.