Delhi Sixth Most Polluted City in India in October 2025; Dharuhera Tops the List
In October 2025, Delhi ranked as the sixth most polluted city in India with a sharp rise in PM2.5 levels to 107 µg/m³, nearly three times higher than September. Dharuhera in Haryana was the most polluted city, with a PM2.5 average of 123 µg/m³. The pollution surge highlights the need for long-term strategies beyond seasonal measures as multiple NCR cities faced severe air quality decline.
According to a study by the Centre for Research on Energy and Clean Air (CREA), Delhi was ranked sixth among the most polluted cities in India in October 2025, registering an average PM2.5 concentration of 107 µg/m³, a threefold increase from its September average of 36 µg/m³. The National Capital Region (NCR), including cities like Ghaziabad, Noida, Rohtak, Ballabgarh, and Gurgaon, showed significant air quality deterioration, largely attributable to persistent emissions from vehicles, industries, and construction activities rather than short-term seasonal factors such as stubble burning, which contributed less than 6% to Delhi's particulate matter. Dharuhera, Haryana, was identified as the most polluted city, recording an alarming PM2.5 average of 123 µg/m³ and violating the National Ambient Air Quality Standard (NAAQS) on 77% of the days, with two 'Severe' and nine 'Very Poor' air quality days during the month. In contrast, Shillong in Meghalaya emerged as the cleanest city with an average of just 10 µg/m³ PM2.5. The grim data suggest the limitations of current seasonal pollution control measures like the Graded Response Action Plan (GRAP), signaling an urgent need for robust, year-round pollution mitigation strategies to protect public health and environmental quality in the NCR and adjoining regions.
