Arrah — Pollution Health Impact
867 days of CPCB data (2021–2024), translated through WHO 2021, Berkeley Earth and EPIC AQLI methods. Based on CPCB station data, 2016–present.
Bihar · Live Arrah AQI →
Living in Arrah is the population-level health-equivalent of smoking 3.7 cigarettes a day — roughly 1,337 cigarettes a year. On average, that chronic exposure shortens life expectancy by about 7.4 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 Arrah meet?
24-hour PM2.5 compliance vs WHO 2021 targets.
- AQG6 days (0.7%)
- IT-415 days (1.7%)
- IT-356 days (6.5%)
- IT-2101 days (11.6%)
- IT-1311 days (35.9%)
- Above IT-1378 days (43.6%)
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 Arrah's 7.4 year estimate.
- Heart + stroke: 5.0y
- COPD: 1.0y
- Child ALRI: 1.0y
- Lung cancer: 0.3y
Worst and best months
Drill into full monthly pattern on the seasonal Arrah page →
High-risk days for vulnerable residents
- Days above WHO IT-3 (37.5 µg/m³) — pregnancy & infant risk elevated
- 790 (91.1%)
- Days above WHO IT-1 (75 µg/m³) — high risk for children under 5
- 378 (43.6%)
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 Arrah compares to nearby cities
What the numbers say
Overview
Arrah's air pollution translates to about 3.7 passive cigarettes per resident per day. That's 1,337 cigarette-equivalents annually, inhaled without choice.
The data story
Using the Air Quality Life Index coefficient from EPIC at the University of Chicago, that long-run exposure reduces average life expectancy by roughly 7.4 years per resident. Of the 867 days on record, only 6 (0.7%) met the WHO 24-hour guideline of 15 µg/m³, while 378 days (43.6%) were above the loosest WHO Interim Target-1 (75 µg/m³).
Why this pattern
Seasonality matters: December is Arrah's worst month (5.9 cigs/day equivalent) and September is the best (2.0 cigs/day). Per WHO's 2024 attribution, 68% of PM2.5-attributable deaths globally come from ischaemic heart disease and stroke, 14% from COPD, 14% from acute lower-respiratory infections in children under 5, and 4% from lung cancer.
What to do with this
These numbers are communication heuristics, not a clinical diagnosis — but they make the stakes legible. Low-cost actions stack: check 24-hour PM2.5 daily, wear an N95 in winter mornings, and run a HEPA purifier indoors during peak months. Pregnant residents and children under 5 are most at risk (WHO 2024) and benefit most from clean-air interventions on the 790 days (91.1%) when PM2.5 sits above WHO IT-3 (37.5 µg/m³).