Coimbatore — Pollution Health Impact
1,005 days of CPCB data (2019–2024), translated through WHO 2021, Berkeley Earth and EPIC AQLI methods. Based on CPCB station data, 2016–present.
Tamil Nadu · Live Coimbatore AQI →
Living in Coimbatore is the population-level health-equivalent of smoking 1.7 cigarettes a day — roughly 628 cigarettes a year. On average, that chronic exposure shortens life expectancy by about 3.2 years per resident.
Cigarette-equivalence (Berkeley Earth 2015) and life-years lost (EPIC AQLI) are peer-reviewed communication heuristics, not clinical diagnoses. Full sources linked on the methodology page.
Headline impact numbers
Cigarettes/day by year
Annual average cigarette-equivalent.
Clean-air days (NAQI ≤ 50) by year
Days when NAQI stayed in the “Good” band.
Which WHO tier did Coimbatore meet?
24-hour PM2.5 compliance vs WHO 2021 targets.
- AQG24 days (2.4%)
- IT-4208 days (20.7%)
- IT-3302 days (30.0%)
- IT-2266 days (26.5%)
- IT-1184 days (18.3%)
- Above IT-121 days (2.1%)
WHO AQG (15) · IT-4 (25) · IT-3 (37.5) · IT-2 (50) · IT-1 (75) µg/m³ (24-hour PM2.5).
Life-years lost, by disease
Applying WHO's global attribution (68/14/14/4) to Coimbatore's 3.2 year estimate.
- Heart + stroke: 2.2y
- COPD: 0.5y
- Child ALRI: 0.5y
- Lung cancer: 0.1y
Worst and best months
Drill into full monthly pattern on the seasonal Coimbatore page →
High-risk days for vulnerable residents
- Days above WHO IT-3 (37.5 µg/m³) — pregnancy & infant risk elevated
- 471 (46.9%)
- Days above WHO IT-1 (75 µg/m³) — high risk for children under 5
- 21 (2.1%)
Source: WHO 2021 AQG interim-target risk framework; WHO 2024 ambient-air fact sheet identifies children under 5 and pregnant residents as the most vulnerable groups.
How Coimbatore compares to nearby cities
- Similar exposureKarur1.9 cigs/day · 3.6 y lost · +0.2 vs Coimbatore
- Similar exposureRanipet1.9 cigs/day · 3.5 y lost · +0.2 vs Coimbatore
- Cleaner peerHassan1.7 cigs/day · 3.2 y lost · -0.0 vs Coimbatore
- Dirtier peerThiruvananthapuram1.8 cigs/day · 3.3 y lost · +0.0 vs Coimbatore
What the numbers say
Overview
Coimbatore's air pollution translates to about 1.7 passive cigarettes per resident per day. That's 628 cigarette-equivalents annually, inhaled without choice.
The data story
EPIC's AQLI research attributes about 3.2 life-years lost per person from this chronic exposure. The WHO Air Quality Guideline was met on just 24 of 1,005 days (2.4%); 21 days (2.1%) exceeded even the 75 µg/m³ Interim Target-1 threshold.
Why this pattern
The burden concentrates in November — when the average cigarette-equivalent climbs to 2.2/day — and eases in August (1.2/day). Globally, WHO attributes 68% of PM2.5 deaths to heart disease and stroke, with the remainder split across COPD, childhood ALRI, and lung cancer.
What to do with this
Cigarette-equivalence is a communication tool, not a medical verdict. Still, the direction is clear: time indoors with a HEPA unit and a good-fit mask outdoors during the 471 days (46.9%) above WHO IT-3 meaningfully lowers exposure — especially for pregnant residents and children under 5.