Record5 September 2026Environment
Tamil Nadu: share of cities with poor air of 20% on 5 September 2026 is the highest since 3 March 2026.
What happened
- 5 September 2026
- 20%
- 2026-03-03
- 20%
Why it matters
A record says how long it has been since the series was this high or this low. It puts a single value in the context of the whole published history.
For share of cities with poor air, lower is better. This movement is therefore assessed as a deterioration.
Historical context
185 consecutive earlier days were lower.
The underlying data
| Period | Value | Release | Where in the document |
|---|---|---|---|
| 5 September 2026 | 20% | CPCB National Air Quality Index bulletin, 5 September 2026 (250 cities) | AQI bulletin p.4–12, Index Value column: 1 of 5 city rows placed in Tamil Nadu at 201 or more — Cuddalore 493 (p.4) |
| 3 March 2026 | 20% | CPCB National Air Quality Index bulletin, 3 March 2026 (243 cities) | AQI bulletin p.4–12, Index Value column: 1 of 5 city rows placed in Tamil Nadu at 201 or more — Gummidipoondi 214 (p.5) |
Source and method
More signals for share of cities with poor air in Tamil Nadu
- Tamil Nadu: share of cities with poor air of 50% on 17 September 2026 is the highest since 13 November 2023.
- Tamil Nadu: share of cities with poor air over the 7 days to 17 September 2026 was 7%, above the 5-year median of 0% for the same week (+7.1 points).
- Tamil Nadu: share of cities with poor air over the 7 days to 10 September 2026 was 6%, above the 5-year median of 0% for the same week (+5.7 points).
Cite this
According to the India Health Observatory, Tamil Nadu: share of cities with poor air of 20% on 5 September 2026 is the highest since 3 March 2026. Source: Central Pollution Control Board, Ministry of Environment, Forest and Climate Change, CPCB National Air Quality Index bulletin, 5 September 2026 (250 cities). https://indiahealthobservatory.com/signals/cities-with-poor-air--tamil-nadu--2026-09-05--record
See also Tamil Nadu and 20% in context.