Delhi India's 6th most polluted city in October; Dharuhera worst— see full list

Even as Delhi is considered to be the most polluted city in India and every year courts and governments discuss over stubble burning and vehicle emissions as the main source, surprisingly, it is not the most polluted city, at least in October 2025. The latest study by the Centre for Research on Energy and Clean Air (CREA) revealed that Delhi is ranked as the sixth most polluted city in India in October 2025, ahead of which are its neighbouring cities like Ghaziabad and Noida.

CREA’s study involved factors like continuous ambient air quality monitoring data, which pointed out an alarming decline in air quality across the country, with the Indo-Gangetic Plain, particularly the National Capital Region (NCR), witnessing the sharpest declines. Among the most polluted cities, Haryana’s Dharuhera ranked first during October 2025, with an alarming average PM2.5 concentration of 123 g/m, greatly surpassing the National Ambient Air Quality Standard (NAAQS) on around 77% of the days.

The city saw two ‘Severe’ and nine ‘Very Poor’ air quality days, highlighting the consistent pollution crisis. During the same time, Delhi's monthly average PM2.5 level stood at 107 g/m, making it almost thrice that of its September average of 36 g/m, underlining a continuous, fast, and shocking rise in air pollution.