India says 108 cities cut PM10. That doesn’t predict winter air.

On 7 September, the Union environment ministry said 108 of the 130 cities in India’s National Clean Air Programme had lower annual-average PM10 in FY2025–26 than in FY2017–18. Seventy-two cities reduced it by more than 20%, 26 by more than 40%, and 14 met India’s annual PM10 standard. The ministry’s backgrounder records a real change in the programme’s headline measure.

That is encouraging, but it does not answer the question people will ask when air turns hazy: will the next bad-air day be safer where I live?

Not from this number alone. It measures a full year’s PM10 average across 130 selected cities. It is not an AQI score, a count of good-air days, a winter forecast or a measure of every pollutant people breathe.

What the 108-city result measures

PM10 means inhalable particles up to 10 micrometres across. Road and construction dust are important contributors, alongside material from burning and industry. India’s annual PM10 standard is 60 micrograms per cubic metre. The government says 14 of the 130 NCAP cities met that standard in FY2025–26, compared with six at the FY2017–18 baseline. A Rajya Sabha answer dated 23 July 2026 gives both figures.

The denominator matters: these are 130 NCAP cities, not every Indian town or every resident. The result says 108 city averages were lower than at the baseline; 22 were not lower. It cannot tell a parent about air outside a school or an outdoor worker about the road where they spend the day.

A lower annual average still matters because it suggests less coarse-particle pollution over the reporting year. On its own, though, it cannot establish why the change happened or what one neighbourhood experienced.

What NCAP changed

India launched the National Clean Air Programme in 2019 across 130 cities in 24 states and Union territories. It asks central, state and city agencies to plan action on road dust, construction and demolition waste, open burning, vehicles, industry and other sources.

The original programme goal was a 20–30% particulate reduction by 2024–25. It was later revised to up to 40% PM10 reduction or meeting the PM10 standard by FY2025–26, compared with FY2017–18. The government described that target change in August 2024.

That work is often practical and local: maintaining dusty road edges, controlling construction waste, preventing waste burning, enforcing industrial rules, improving public transport and checking vehicle emissions. The government says it released ₹16,423.56 crore in performance-based incentive grants to targeted cities from FY2019–20 through FY2025–26. That is money released for air-pollution measures, not a direct measure of pollution removed or proof that every project worked. The July parliamentary answer gives the amount and period.

NCAP operated alongside other changes, including Bharat Stage VI fuel and vehicle standards, state enforcement and, in Delhi-NCR, the Commission for Air Quality Management. Weather and economic activity changed too. A before-and-after annual result cannot isolate NCAP’s share from this wider mix.

PM2.5 is a separate and tougher test

PM10 is not the whole health picture. PM2.5 is much finer particulate matter that can travel deeper into the lungs and enter the bloodstream. India’s annual PM2.5 standard is 40 micrograms per cubic metre; the World Health Organization’s health-based annual guideline is 5. WHO’s annual PM10 guideline is 15. WHO sets out both values here. These guidelines are not India’s legal limits, but they show why meeting one metric does not end the health question.

The government’s own FY2025–26 data makes that distinction concrete. It says 65 of 130 NCAP cities met India’s PM2.5 annual standard. Among the five major cities named in the parliamentary answer, annual PM2.5 was 41 in Pune, 34 in Hyderabad, 32 in Surat, 102 in Delhi and 33 in Mumbai. Those values are in the same official answer.

The distinction matters for children, older people, people with heart or lung conditions, and workers outside, including traffic police, vendors and construction workers. A city can improve a dust-heavy PM10 average while fine-particle exposure from combustion, traffic, industry and burning remains high. A nationwide study estimated that PM2.5 exposure above India’s annual standard was attributable to 3.8 million deaths over 2009–19. That is a modelled estimate for a decade, not a count for 2026 or a measure of NCAP’s effect. Read the study.

Why the annual result cannot forecast winter

Winter pollution depends on emissions and on the atmosphere. Cold, still conditions can trap air close to the ground beneath warmer air above it. Weak winds and regional transport can let pollution accumulate; rain and stronger mixing can clear it. A yearly average includes cleaner monsoon months as well as stagnant winter weeks.

Careful evaluation therefore adjusts for season and meteorology. A Health Effects Institute assessment of 2017–24 regulatory data says weather-normalised analysis sharpens trends. It also finds that overlapping national interventions, local measures, economic change and weather complicate any claim that NCAP alone caused the observed change.

Monitoring is another limit. CREA reported that 28 NCAP cities lacked a continuous monitor in 2024 and only 97 had at least 80% PM10 data coverage. Its 2025 review is independent research, not an official audit. The finding is still a useful warning: a city average cannot show whether monitors cover the places where exposure is highest.

What would make the next claim more useful

The annual PM10 result is progress in the measure it reports. To help people judge what their city has achieved, cities should publish complete, validated PM10 and PM2.5 data; disclose where monitors are and whether they worked; list funded projects and their maintenance; and show how projects match identified pollution sources.

Swachh Vayu Survekshan, the government’s annual awards exercise, answers a different question. It evaluates documented action on dust, waste, vehicles, industry, construction and outreach through city self-assessment, state approval, CPCB evaluation and independent field verification. MoEFCC describes the process here. An award can recognise implementation; it does not establish that a winning city has the lowest pollution exposure.

This winter, the more revealing evidence will be complete daily PM2.5 and PM10 readings, the response when episodes build, and whether city governments can show how their spending reduced the sources behind those readings.