Delhi chokes as AQI levels hit 500-mark several times on Sunday

Among the worst affected areas were Jahangirpuri and Mundka — both recording an AQI of 499, Bawana at 498 and other regions which neared the 500 mark.

The air quality index (AQI) at least three of Delhi’s stations maxed out at the 500-mark at various times on Sundayas all of 38 of the 39 active monitoring stations in the Capital hovered in the ‘severe’ and ‘severe-plus’ categories.

Residents said the air looked like dense fog and it was difficult to even breathe outdoors (Arvind Yadav/HT)

The Central Pollution Control Board’s (CPCB) 24-hour average air quality index (AQI) at the Wazirpur, Rohini, and Ashok Vihar stations reached 500. The CPCB’s AQI readings do not go beyond 500 – meaning the actual exposure, particularly hourly readings – would be much higher.

Among the other stations, at least 13 stations saw AQI levels hovering above 490 for several hours on Sunday, with several locations nearly maxing out.

Among the worst affected areas were Jahangirpuri and Mundka — both recording an AQI of 499, Bawana (498), Delhi Technical University (497), Vivek Vihar (497), Narela (493), Anand Vihar (492), IHBAS in Dilshad Garden (491) and Okhla Phase-2 (490).

The best AQI of Sunday was recorded at Shadipur at a dismal 375 in the “very poor” zone.

As per the CPCB’s guidelines, an AQI of 51 to 100 is classified as “satisfactory”, and between 101 and 200 is classified as “moderate”, between 201 and 300 is “poor”, between 301 and 400 is “very poor”, and over 400 is “severe”.

Residents from these heavily impacted areas said the air looked like dense fog and it was difficult to even breathe outdoors.

It has become difficult to breathe both inside and outside of the house,” said 53-year-old Naveen Garg, president of the RWA in Rohini’s Sector 16.

“Instead of going out early in the morning, people are leaving houses for a walk at around 9-10 am. Residents and the government are aware, and are doing their part but the suffering due to pollution continues,” he added.

At Anand Vihar, president of the DDA-flat Resident Welfare Association, Vinod Kumar said vehicular pollution was choking locals. “Anand Vihar is the hub for all means of transport. We have the bus terminal, railway station and metro station, just one next to the other. Lakhs of visitors in the locality everyday get exposed to vehicular emissions.”

At Ashok Vihar, AQI touched 490 at 9pm on Saturday and stayed above that level throughout the day on Sunday. It settled at 499 for several hours before hitting 500 at 7pm.

On Sunday, Nehru Nagar in Lajpat Nagar settled at 493 and saw the hourly PM2.5 concentrations spike to 720 micrograms per cubic metre (μg/m³) at 11pm.

The average hourly PM 2.5 concentration peaked at levels which were 10-12 times the national daily ambient air quality standard of 60 μg/m³ and 48-50 times the World Health Organization’s daily safe guideline of 15 μg/m³.

Other parts of the city witnessed similar conditions. Peak hourly PM2.5 concentrations on Sunday touched 660 μg/m³ at RK Puram, while Anand Vihar recorded levels as high as 651 μg/m³, according to data from the Delhi Pollution Control Committee (DPCC).

Sunil Dahiya, founder and lead analyst at think tank Envirocatalysts, said scientific evidence globally shows that long-term exposure to PM2.5 levels above 5 μg/m³ is associated with adverse health impacts.

“What we are breathing currently is PM2.5 levels above 500 μg/m³. It is not just a cause of long-term health impacts such as respiratory diseases, COPD, lung cancer, etc., and cardiovascular diseases such as heart attacks, stroke, heart failure, but also results in emergency hospitalisation due to asthma attacks and stroke,” Dahiya said.

Last winter, the AQI had maxed out at 15 stations on November 18, when Delhi recorded its second-highest AQI ever at 494.

Mohammad Rafiuddin, programme lead at the Council on Energy, Environment and Water (CEEW), warned that even short-term exposure to such pollution levels could be dangerous. “Residents must wear masks since even a short-term exposure to such levels of air pollution can cause health complications,” he said.