Delhi Air Pollution: PM2.5 Data Row Erupts Post-Diwali

The Cliff News | 9 November 2026

Delhi's air quality plummeted to alarming levels on the night of November 8, 2026, following widespread firecracker use long after permitted hours on Deepavali. The national capital is currently under Stage III of the Graded Response Action Plan (GRAP), with numerous restrictions in place to combat severe pollution.

A significant controversy has emerged after senior Congress leader Ajay Maken highlighted the absence of PM 2.5 readings from 25 of Delhi’s 39 air quality monitoring stations during the critical hours of Diwali night. He noted that where data was available, pollution levels at nine stations reached an alarming 38.4 times the World Health Organisation’s (WHO) 24-hour limit.

Allegations of Data Discrepancies

Mr Maken took to X to express his concerns, alleging discrepancies in the capital's air pollution monitoring system. He pointed out that PM 2.5 readings were reportedly not recorded between 2 AM and 3 AM on the festival night across a substantial number of stations.

The specific stations cited by Mr Maken, based on Central Pollution Control Board (CPCB) data, include Anand Vihar, Ashok Vihar, Aya Nagar, Bawana, CRRI Mathura Road, Chandni Chowk, Dwarka Sector 8, IMD Lodhi Road, ITO, Jawaharlal Nehru Stadium, Mandir Marg, Mundka, NSIT Dwarka, Najafgarh, Narela, Nehru Nagar, North Campus DU, Okhla Phase 2, Punjabi Bagh, Pusa, R K Puram, Shadipur, Sirifort, Sri Aurobindo Marg, and Wazirpur.

Political Accusations Fly

The Aam Aadmi Party (AAP) also joined the fray on November 9, launching a direct attack on the Bharatiya Janata Party (BJP) over alleged "manipulation" of air quality data. AAP Delhi president Saurabh Bharadwaj questioned the credibility of a government that, in his view, shuts down monitoring stations during critical pollution periods.

“The government which shuts down air quality monitoring stations on the night of Diwali, the government that does data fraud, how will you trust such a government?”

In a video posted on X, Mr Bharadwaj accused the ruling party of data fraud, underscoring the public's reliance on accurate information during pollution crises.

Counter-Allegations and Stubble Burning

Reacting to the AAP's claims, Delhi labour minister and BJP leader Kapil Mishra alleged a "conspiracy" orchestrated by the AAP-governed Punjab. He claimed that stubble burning in Punjab on Diwali evening was significantly higher than on previous days, citing official data.

Mr Mishra stated that 1,200 stubble burning incidents were recorded in Punjab on Diwali evening, a tenfold increase compared to other days. He alleged that farmers reported individuals setting stubble alight and fleeing, suggesting a deliberate act against Delhi and Punjab while farmers were celebrating with their families. He described this as a "serious issue and a conspiracy against Delhi, Punjab, and farmers."

Understanding Air Quality Metrics

The CPCB categorises Air Quality Index (AQI) as follows: 0-50 is ‘good’, 51-100 ‘satisfactory’, 101-200 ‘moderate’, 201-300 ‘poor’, 301-400 ‘very poor’, and 401-500 ‘severe’.

What is Particulate Matter (PM)?

Particulate matter, or particle pollution, is a complex mixture of solid and liquid particles suspended in the air. These particles are often microscopic, visible only under an electron microscope. They encompass a wide array of substances including sulphates, nitrates, black carbon, metals like cadmium, copper, nickel, and zinc, as well as hydrocarbons.

Additionally, biological components such as pollen, dust mites, and fungal compounds are also classified as particulate matter. The two primary sizes of concern are PM 10 and PM 2.5.

• PM 10: These are inhalable particles generally with diameters up to 10 micrometres. For context, the average human hair is about 70 micrometres in diameter.
• PM 2.5: These are fine inhalable particles, measuring 2.5 micrometres and smaller.

Health Impacts of Air Pollution

The extremely fine PM 2.5 particles, approximately 30 times smaller than a human hair, pose significant health risks. They can penetrate deep into the respiratory tract, settle in the lungs, and even enter the bloodstream, leading to both immediate and chronic health problems.

Both PM 2.5 and PM 10 can cause irritation to the eyes, nose, and throat, along with symptoms like breathlessness, headaches, coughing, and sneezing. Prolonged exposure to PM 2.5 is particularly concerning and can be fatal, as it affects multiple organs and exacerbates pre-existing health conditions.

Current Air Quality Status in Delhi

As of publication, Delhi's AQI is reported at 208 on an open-source air quality monitoring platform, AQI.in. The corresponding PM 2.5 level stands at 132 µg/m³, with PM 10 at 164 µg/m³, indicating a ‘poor’ to ‘very poor’ category air quality.

Future Air Quality Forecast

The Air Quality Early Warning System has predicted that Delhi's air quality is likely to remain in the ‘severe’ category throughout the day and for the subsequent few days. Unfavourable meteorological conditions, vehicular emissions, and ongoing stubble burning in neighbouring states are identified as the primary contributors to this anticipated deterioration.