Delhi 6th most polluted city in Oct: Study

Delhi was the sixth most polluted city in India in October, according to new data from the Centre for Research on Energy and Clean Air (CREA), an independent research organisation that analyses air pollution patterns, sources, health effects and potential solutions.

The findings show that air quality across the Indo-Gangetic Plain (IGP), especially in the National Capital Region (NCR), has deteriorated sharply over the past month.

The study, based on data from Continuous Ambient Air Quality Monitoring Stations (CAAQMS), found that Dharuhera in Haryana topped the list as the most-polluted city, recording an average PM2.5 concentration of 123 µg/m³, more than twice the national safety limit. It breached the National Ambient Air Quality Standard (NAAQS) on 77 per cent of days in October, including two “severe” and nine “very poor” air quality days.

Delhi, with a monthly average PM2.5 level of 107 µg/m³, saw pollution levels nearly triple from its September average of 36 µg/m³. The Capital ranked behind Ghaziabad, Noida, and Ballabgarh, all within the NCR region, underlining the growing concentration of air pollution in north India.

The CREA report notes that farm fires contributed less than 6 per cent of Delhi’s PM2.5 levels in October. The rest came from year-round sources such as vehicular emissions, industrial activity, road dust and construction.

Delhi’s air quality crisis is now a round-the-year problem. The focus needs to shift from short-term emergency plans to sustained emissions control, the report said, calling for stronger policies beyond seasonal responses like the Graded Response Action Plan (GRAP).

Among India’s ten most polluted cities, four were from Uttar Pradesh and four from Haryana, highlighting the NCR’s worsening regional air sheds. Following Dharuhera, the most polluted cities were Rohtak, Ghaziabad, Noida, Ballabgarh, Delhi, Bhiwadi, Greater Noida, Hapur, and Gurgaon.

In contrast, Shillong (Meghalaya) recorded the cleanest air in the country, with a PM2.5 concentration of just 10 µg/m³. Cities from Karnataka, Tamil Nadu, Sikkim and Chhattisgarh were listed among the cleaner ones.

Out of the 249 cities monitored, 212 met India’s NAAQS limit of 60 µg/m³, but only six cities complied with the World Health Organisation’s stricter standard of 15 µg/m³.

The number of cities with ‘good’ air quality fell drastically from 179 in September to 68 in October, while those in ‘poor’ and ‘very poor’ categories increased.