New Delhi: Anand Vihar, Wazirpur, Bawana, Jahangirpuri and Vivek Vihar have been the most polluted stations in Delhi so far this winter season.
Delhi Technical University (DTU), Lodhi Road and Sri Aurobindo Marg have turned out to be the least polluted stations, but their average PM2.5 concentration was still higher than the national ambient air quality standard.
An analysis of Central Pollution Control Board’s hourly PM2.5 levels from Oct 1 to Dec 8 has revealed that Anand Vihar’s PM2.5 concentration was the highest at 221 micrograms per cubic metre, followed by Wazirpur at 214 and Bawana at 213.
In Nov, Anand Vihar recorded mean PM2.5 levels of 314 micrograms per cubic metre, compared to the daily national ambient air quality standard of 60 micrograms per cubic metre.
Data shows that all the top five polluted locations are among the 13 hotspots. Delhi Pollution Control Committee and CPCB had identified 13 pollution hotspots in 2018. The annual PM2.5 concentration at these spots was higher than the mean PM2.5 level of the entire city. The 13 spots are Anand Vihar, Mundka, Wazirpur, Jahangirpuri, RK Puram, Rohini, Punjabi Bagh, Okhla, Bawana, Vivek Vihar, Narela, Ashok Vihar and Dwarka.
Sunil Dahiya, founder of Envirocatalysts, said: “Wazirpur, Bawana and Jahangirpuri are industrial areas, and Vivek Vihar is next to an industrial area. Traffic is a major concern at Anand Vihar, a transport intersection. Since hotspots continue to record high pollution levels, more needs to be done.”
He added that more aggressive steps should be taken for efficient control of emissions, including ensuring that all industries use cleaner fuels, switch to electric vehicles and reduce the number of private vehicles.
DTU recorded the lowest average PM2.5 concentration at 98 micrograms per cubic metre, followed by Lodhi Road (IITM station) and Sri Aurobindo Marg that recorded average PM2.5 levels of 120 micrograms per cubic metre. Another station at Lodhi Road recorded 128 micrograms per cubic metre.
“Pollution level at a location is influenced by local sources. There has been a variation in data of some stations compared with the city average. Such a station might not be collecting proper data due to obstruction from a tree or a tall building,” Dahiya said. He recommended a proper audit of the sighting and calibration of all stations.
Dipankar Saha, former head of CPCB’s air laboratory, said: “The emission load varies with time and land use while the ventilation coefficient is governed by the atmospheric boundary layer and wind speed. Meteorological conditions influence the ventilation.”
