Ghaziabad most polluted city during winter: Report

The CERA analysis further revealed that at least 204 of 238 Indian cities with sufficient monitoring data recorded average winter PM2.5 concentrations above NAAQS, up from the last year's 173 cities. The study is based on Continuous Ambient Air Quality Monitoring Stations (CAAQMS) data from the Central Pollution Control Board (CPCB) between October 1, 2025 and February 28 this year, CREA said.

None of the analysed cities met the World Health Organisation’s (WHO) PM2.5 guideline of 5 µg/m³. In the previous winter too, no city complied with the WHO limit.

Of the 96 cities covered under the National Clean Air Programme (NCAP), 84 recorded average PM2.5 concentrations above India's NAAQS. All 96 cities exceeded the WHO guideline.

During the winter 2025-26 period, Delhi experienced 18 ‘severe’ days, 87 ‘very poor’ days, 24 ‘poor’ days, 15 ‘moderate’ days, six ‘satisfactory’ days, and only one ‘good’ day. Greater Noida, Bahadurgarh, Dharuhera, Gurgaon, Bhiwadi, Charkhi Dadri and Baghpat were the 10 most polluted cities, with Greater Noida ranking fourth and Baghpat tenth. Uttar Pradesh and Haryana accounted for four cities each among the top 10 most polluted cities, along with one city each from Delhi and Rajasthan, the analysis showed.

“The comparison between the last two winters shows that widespread non-compliance continues, with more cities breaching the national standard in winter 2025-26 than in the previous winter. While the Commission for Air Quality Management (CAQM) has set PM2.5 reduction targets for the NCR region, similar nationwide PM2.5 reduction targets are needed with a stronger focus on controlling gaseous pollutants such as sulphur dioxide, nitrogen dioxide and volatile organic compounds, which contribute to the formation of secondary PM2.5 and ozone, a major component of particulate pollution’, said Manoj Kumar, India Analyst, CREA.