Delhi Second Most Polluted City In January: CREA Report

Delhi ranked as the second most polluted city in India in January 2026, trailing only Ghaziabad, according to a monthly analysis by the Centre for Research on Energy and Clean Air (CREA). The findings underline the persistent severity of winter air pollution in north India and continued non-compliance with both national and global air quality standards.

PM2.5 levels far above national limits

Delhi recorded a monthly average PM2.5 concentration of 169 micrograms per cubic metre in January. This level is nearly three times higher than India’s National Ambient Air Quality Standards (NAAQS) annual limit of 60 micrograms per cubic metre. Fine particulate matter remained elevated for most of the month, reflecting unfavourable meteorological conditions and sustained emission sources.

Ghaziabad tops pollution ranking

Ghaziabad emerged as the most polluted city in the country during the month. It recorded an average PM2.5 concentration of 184 micrograms per cubic metre and breached the daily national standard on all 31 days of January. The data highlight the acute air quality stress across the National Capital Region.

Air quality categories and daily exposure

According to CREA’s analysis, Delhi experienced 24 ‘Very Poor’ days, three ‘Severe’ days, two ‘Poor’ days and only two ‘Moderate’ days in January. As per the Central Pollution Control Board, an Air Quality Index between 301 and 400 is classified as ‘very poor’, while readings above 400 fall under the ‘severe’ category, posing serious health risks.

Important Facts for Exams

• India’s PM2.5 annual standard is 60 µg/m³, higher than WHO guidelines.
• WHO daily safe guideline for PM2.5 is 15 µg/m³.
• NCAP aims to reduce PM pollution in selected non-attainment cities.
• PM2.5 particles can enter the bloodstream and affect multiple organs.

National trends and policy concerns

The report noted that 123 out of 248 cities across India recorded monthly average PM2.5 levels above national standards, while none met the World Health Organization’s daily safe guideline. Among cities covered under the National Clean Air Programme, air quality remained largely non-compliant. CREA analysts emphasised the need to refocus the programme on PM2.5 and its precursor gases, such as sulphur dioxide and nitrogen dioxide, adopt stricter emission norms for industries and power plants, and move towards an airshed-based management approach.