ABP Exclusive | Delhi’s PM10 Levels Cross 3,490 After Diwali, CPCB App Misses Peak Pollution Data

Delhi witnessed widespread firecracker celebrations on Diwali night, resulting in a sharp rise in air pollution across the national capital. The extent of the pollution was visible in the city's skies on Sunday morning, with a thick blanket of smog reducing visibility in several areas.

An exclusive ABP News investigation has found that PM10 levels in several parts of Delhi crossed 3,000, 2,000 and 1,000 between 11 pm and 5 am after firecrackers were burst during Diwali celebrations. The investigation also found that the Central Pollution Control Board (CPCB), under the Union government, did not display the peak pollution readings recorded during these hours on its SAMEER app.

Instead, the app showed data from later hours, when PM10 levels had dropped below 500. According to data from the Delhi Pollution Control Committee (DPCC), PM10 levels in Anand Vihar crossed 3,000 at midnight and peaked at 3,490 at 2 am.

At Mandir Marg in Lutyens' Delhi, PM10 levels crossed 2,000 at 2 am, reaching 2,506, before climbing to a peak of 3,124 at 4 am. The readings from other locations were also alarming: At 8:30 am on Sunday, Delhi's average Air Quality Index (AQI) stood at 368, placing it in the 'very poor' category.

Data from 54 of the 59 operational AQI monitoring stations showed that 15 stations had recorded AQI levels above 400, falling in the 'severe' category, at 8 am. At 35 monitoring stations, the AQI was above 300, placing them in the 'very poor' category.

Only four stations — Delhi Cantonment, IGNOU, Maidan Garhi and Aurobindo Marg — recorded AQI levels in the 'poor' category, above 250. Visuals from Akshardham in Delhi at 8 am showed the temple surrounded by a thick layer of toxic smog.

Visibility had dropped to just 50 metres, making the temple barely visible. Environmental expert Dr Manu Singh attributed the sharp rise in PM10 levels to several factors, including stagnant winds in the national capital even before Diwali, firecrackers being burst beyond the permitted time despite the Supreme Court's order, and stubble burning in neighbouring states.

While the DPCC's monitoring stations recorded peak PM10 levels crossing 3,000, 2,000 and 1,000 in several parts of Delhi, the CPCB's SAMEER app did not display the corresponding readings from these monitoring stations during the peak pollution hours.

An examination of the data from Mandir Marg, Anand Vihar and Patparganj revealed gaps in the readings displayed on the CPCB app. At Mandir Marg, the DPCC graph showed that PM10 levels had reached 3,124 at 4 am. However, the SAMEER app did not display any PM10 data from the DPCC monitoring station between 11 pm and 5 am.

Instead, after showing the 10 pm reading, the app directly displayed the 6 am reading. A similar gap was found in the data for Anand Vihar. The SAMEER app did not show PM10 readings between 10 pm and 2 am, when the level peaked at 3,490 at 2 am.

After displaying the 9 pm reading, the app directly showed the 3 am reading, when PM10 levels had dropped to 438. At Patparganj, the DPCC data showed that PM10 levels stood at 2,889 at midnight. However, the CPCB app did not display readings between 9 pm and 5 am.

After showing the 8 pm reading, it directly displayed the 6 am reading, when the PM10 level was 394. Environmental experts have questioned why the CPCB's app did not display the peak readings recorded by DPCC monitoring stations.

They have also raised concerns over whether authorities are prioritising social media management over public health during severe pollution episodes. The DPCC also updated its data on Sunday, releasing PM10 readings that showed levels crossing 1,000, 2,000 and 3,000 in several parts of Delhi.