The national capital is gasping for breath once more, as Delhi&rsquo;s air quality plunged into the "severe" category on Sunday, November 2, just two weeks after Diwali.&nbsp;
The city&rsquo;s overall Air Quality Index (AQI) crossed 400, marking a sharp deterioration from Saturday&rsquo;s reading of 303.
Experts warn that deaths linked to air pollution in Delhi have remained persistently high in recent years, with the toll rising from 15,786 in 2018 to 17,188 in 2023.
The air at several locations in the capital, including AIIMS, registered an AQI of 421 on Sunday morning, signalling hazardous conditions. 
Thick smoke and shallow fog blanketed the city, significantly reducing visibility.
According to the India Meteorological Department (IMD), the smog formation was due to the combined effect of fog and pollution particles suspended in the air. 
&ldquo;Shallow fog mixed with smoke prevailed over several areas of Delhi,&rdquo; an IMD expert said.
Data from the Central Pollution Control Board (CPCB) showed that most monitoring stations recorded "Severe" or "Very Poor" levels of air quality. 
At 8 am, AQI readings were: Anand Vihar (298), Alipur (258), Ashok Vihar (404), Chandni Chowk (414), Dwarka Sector-8 (407), ITO (312), Mandir Marg (367), Okhla Phase-2 (382), Patparganj (378), Punjabi Bagh (403), RK Puram (421), Lodhi Road (364), Rohini (415), and Sirifort (403).
The city has remained under "Poor" to "Very Poor" air quality categories since Diwali, even as Stage 2 of the Graded Response Action Plan (GRAP) remains in force.
According to the Centre for Research on Energy and Clean Air (CREA), air pollution remains Delhi&rsquo;s biggest health hazard, responsible for nearly 15% of all deaths in 2023. 
Despite some annual fluctuations, deaths attributable to particulate matter pollution have stayed alarmingly high , often surpassing those from hypertension or diabetes.
&ldquo;Air pollution is not just an environmental issue; it&rsquo;s a public health crisis that demands science-based interventions across all polluting sectors,&rdquo; said Manoj Kumar, an analyst at CREA. 
&ldquo;Unless Delhi&rsquo;s air quality improves substantially, pollution-related diseases such as respiratory illnesses, heart disease, stroke, and lung cancer will continue to rise.&rdquo;
Union Minister of State for Environment Kirti Vardhan Singh, however, stated in the Rajya Sabha that while air pollution is a serious concern, it cannot be isolated as the sole cause of mortality. 
&ldquo;Health is influenced by multiple factors, including food habits, occupational exposure, socio-economic conditions, heredity, and immunity,&rdquo; he said.
As the toxic haze thickens over the capital, experts urge immediate, science-backed action to prevent further escalation of Delhi&rsquo;s long-standing air pollution crisis.

Two weeks after Diwali, Delhi’s air quality plunges to ‘severe’ levels with AQI at 421

Delhi's AQI Hits 421, Air Turns 'Severe'

Two weeks after Diwali, Delhi’s air quality plunges to ‘severe’ levels with AQI at 421

November 2, 2025 | 10:16 IST