A new study has revealed that Delhi could finally meet India’s national clean air standard by 2040, but only if the city implements emission cuts similar to those during the Covid-19 lockdown. The working paper, titled “40 by 2040: Cost of inaction and delays in reaching Delhi’s air quality target,” examines Delhi’s PM2.5 levels over the last 36 years, from 1989 to 2025.
Researchers Sarath Guttikunda and Sai Krishna Dammalapati from the environmental advocacy group Urban Emissions conducted the analysis. They say the city must make deep and sustained cuts in pollution from multiple sources to reach the Central Pollution Control Board’s (CPCB) annual safe limit of 40 µg/m³ for PM2.5.
Pollution Levels Still Extremely High
Despite several policies and public announcements over the years, Delhi’s annual average PM2.5 concentration has hardly improved. Between 2019 and 2025, the study found the city’s pollution levels stayed around 100 µg/m³, which is:
- 2.5 times higher than India’s national standard (40 µg/m³)
- 20 times higher than the World Health Organisation (WHO) guideline of 5 µg/m³
This persistent pollution, the researchers say, is not due to a lack of scientific understanding or policy frameworks. Instead, it results from slow implementation of measures already identified in the National Clean Air Programme (NCAP).
What Needs to Change
To meet the clean air target by 2040, the study suggests a combination of bold measures, including:
- Up to 55% reduction in pollution from all human-made sources
- 75% reduction in winter heating emissions
- 100% elimination of stubble burning emissions
These cuts, the researchers argue, mirror the drastic change seen during the Covid-19 lockdown, when industries, traffic, and other pollution sources were significantly reduced.
Health and Financial Risks of Delayed Action
The study also highlights the serious consequences of not acting quickly. If Delhi reduces its PM2.5 levels to only 60 µg/m³ by 2040 instead of the target 40 µg/m³, the city will see:
- 11.6% more exposure cases – meaning more people will suffer health risks.
If pollution remains at 100 µg/m³, the numbers become even more alarming:
- 35.3% more deaths for every 100 deaths estimated under the clean-air scenario.
These findings show that inaction and delays come with heavy health and economic costs.
Lockdown as an Example of What’s Possible
The researchers used the Covid-19 lockdown as proof that steep pollution reductions are technically achievable. During the lockdown, the only major sectors that continued functioning were:
- Winter heating (which is seasonal and does not affect summer months)
- Agricultural stubble burning (which is also minimal during spring months)
With transport, industry, and construction slowed, Delhi saw a dramatic improvement in air quality. This shows what cleaner air could look like if long-term, sustainable changes are made.
A Clear Message: Act Now
The study concludes that Delhi has the knowledge and tools needed to achieve clean air. What it needs now is swift, strict, and sustained action. Without this, the city risks decades of unnecessary illness, deaths, and financial loss.
Cleaner air is possible, but only if leaders and communities act with urgency, matching the drastic pollution reductions seen during the Covid-19 lockdown.
