Vans to monitor bad air at 13 pollution hot spots in Delhi

The goal is to develop local and regional policies to improve Delhi’s air quality, said environment minister Gopal Rai.

Delhi’s environment minister, Gopal Rai, on Monday unveiled plans to station mobile vans across the city’s 13 pollution hotspots for a week to pinpoint individual pollution sources for targeted action. Rai announced the move after he held a round-table conference to evaluate a real-time source apportionment study initiated in January, which identified secondary inorganic aerosols and vehicle emissions as the primary pollutants in the Capital.

Data from the government’s supersite at Sarvodaya Bal Vidyalaya, Rouse Avenue, revealed that secondary inorganic aerosols — particles formed in the air because of gases reacting with each other from combustion sources — is the primary source of pollution in the Capital, followed by vehicle emissions. (PTI)

“We have issued orders to deploy mobile air quality monitoring stations at Delhi’s 13 pollution hotspots, which will provide real-time data for prompt response to pollution rises,” said Rai.

Data from the government’s supersite at Sarvodaya Bal Vidyalaya, Rouse Avenue, revealed that secondary inorganic aerosols — particles formed in the air because of gases reacting with each other from combustion sources — is the primary source of pollution in the Capital, followed by vehicle emissions.

“The real-time study has been instrumental in identifying pollution sources and trends, facilitating swift government response to pollution spikes. In addition, it has enabled more accurate monitoring of PM2.5, NO2, NOx, CO, SO2, ozone, secondary inorganic, and organic aerosols,” said Rai.

Seasonal data presented during the conference showed that secondary inorganic aerosols accounted for 33% of Delhi’s total PM 2.5 pollution load from November to January, with biomass burning (24%) and vehicles (17%) following. The same sources remained significant in February and March, contributing 26%, 22%, and 15%, respectively.

However, data indicates that these sources shift, with vehicles contributing more pollution during summer months at 23%, followed by secondary inorganic aerosols (18%), and soil, road dust, coal, and fly ash each contributing 15%. This data was collected by a site established in November 2022 by IIT Kanpur in collaboration with IIT Delhi and The Energy and Resources Institute (TERI), and officially inaugurated by chief minister Arvind Kejriwal in January.

The conference, attended by officials from government departments such as the environment department, Delhi Pollution Control Committee (DPCC), the Municipal Corporation of Delhi, and air pollution experts from bodies like TERI, IIT Kanpur, Centre for Science and Environment (CSE), the United Nations Environment Programme and the World Bank , aimed to pool knowledge on using real-time data and enhancing its functionality.

“The ultimate goal is to develop local and regional policies to improve Delhi’s air quality, with a second conference planned for next month to further these discussions,” said Rai.

Anumita Roychowdhury, executive director of research and advocacy at CSE, noted that while source profiles vary between summer and winter, vehicle emissions are a consistent pollution source.

“Vehicles are the second biggest pollutant in the winter months, and they become the lead source in the summer period when aerosol formation is reduced slightly. This shows that we need to prioritise cracking down on vehicular pollution and investigate the increased prominence of coal and fly ash in the summer months,” said Roychowdhury.