Delhi Records Highest PM2.5 Levels In India; 447 Districts Breach Air Quality Standard: Report

Delhi has emerged as India's most polluted state, recording the country's highest PM2.5 levels, while 447 districts nationwide have exceeded the national air quality limit, according to a new report. The analysis, based on satellite data from March 2024 to February 2025, shows that Delhi's annual PM2.5 concentration stands at 101 micrograms per cubic metre-2.5 times the Indian standard and 20 times the WHO guideline.

The study, conducted by the independent research organisation Centre for Research on Energy and Clean Air, ranks Chandigarh second with an annual average PM2.5 level of 70 micrograms per cubic metre, followed by Haryana at 63 and Tripura at 62. Other states exceeding the national limit of 40 micrograms per cubic metre include Assam (60), Bihar (59), West Bengal (57), Punjab (56), Meghalaya (53), and Nagaland (52).

Out of the 749 districts assessed, 447 districts-or 60 per cent-breached the National Ambient Air Quality Standard (NAAQS) for annual PM2.5. The most polluted districts are concentrated in a handful of states: Delhi and Assam each account for 11 of the top 50 districts, nearly half the list. Bihar and Haryana contribute seven districts each, while Uttar Pradesh has four, Tripura three, and Rajasthan and West Bengal two districts each.

In several states, every monitored district exceeded the NAAQS, including Delhi, Assam, Punjab, Haryana, Chandigarh, Himachal Pradesh, Meghalaya, Tripura, and Jammu and Kashmir.

Other states also showed widespread violations, such as Bihar (37 of 38 districts), West Bengal (22 of 23), Gujarat (32 of 33), Nagaland (11 of 12), Rajasthan (30 of 33), and Jharkhand (21 of 24).

The study excludes Ladakh, Andaman and Nicobar Islands, and Lakshadweep due to insufficient ground monitoring data during the assessment period.