New Delhi: Contrary to the popular belief about Delhi air pollution, stubble burning contributes only 4 percent of particulate matter (PM) in winter and 7 percent in summer, while industry and transport contribute the most both during winters and summers, the Lok Sabha was told. In a written response to a question raised in the House on December 4, Minister of State (MoS) for Environment, Forest and Climate Change Ashwini Kumar Choubey shared TERI-ARAI Source Apportionment study of year 2016 published in 2018, according to which, industry is responsible for contributing 30 percent and 22 percent of PM2.5 and 27 percent and 22 percent of PM10 in winters and summers, respectively. Transport, on the other hand, contributes 28 percent and 17 percent of PM2.5 and 24 percent and 15 percent of PM10 in winters and summers, respectively.
Data also showed that dust from soil, roads and construction contribute heavily to the concentration of particulate matter in the air during dry weather conditions in summers. Dust accounts for 17 percent of PM2.5 and 25 percent of PM10 in winters, it contributes 38 percent of PM2.5 and 42 percent of PM10 in summers.
Residential pollution contributes 10 percent of PM2.5 in winters and 8 percent in summers, while it accounts for 9 percent of PM10 in winters and 8 percent in summers. The study attributed other sources for contributing 11 percent of PM2.5 in winters and 8 percent in summers and 10 percent PM10 in winters and 7 percent in summers. It did not specify what these other sources are.
The minister told the House that the data of Air Quality Index (AQI) shows that in all Delhi - NCR cities, there are more number of days in Poor, Very Poor and Severe category of AQI in November than other major metro cities of India. “However, the data of AQI of major metropolitan cities indicates there are more number of days in Good, Satisfactory & Moderate category of AQI during November month of 2023as compared to city Delhi – NCR,” said Choubey.
The minister added that there has been a gradual decline in the concentration of PM2.5 and PM10 in Delhi air between 2016 and 2022. While the level of PM10 has reduced from 291 in 2016 to 211 in 2022, PM2.5 has reduced from 135 in 2016 to 98 in 2022.