Diwali pollution this year higher than 2019: DPCC
Delhi’s overall pollution levels this Diwali were higher than last year, shows an analysis by the Delhi Pollution Control Committee (DPCC).
“All pollutants recorded much higher levels on Diwali (November 14) this year as compared to the same in 2019. Besides, a gradual rise in particulate matter (PM) concentrations were observed in the days preceding the festival,” the analysis stated.
Delhi recorded an overall average AQI of 414 on Diwali day this year. Last year, it had recorded an average AQI of 337 on Diwali (October 27).
Higher levels of PM 2.5 (the most harmful aerosols in Delhi’s air) and PM 10 (coarse dust particles) were reported this year at all 13 hot spots as compared to last year. Higher concentrations of pollutants such as carbon monoxide (CO), sulphur dioxide (SO2) and oxides of nitrogen (No2), all of which are harmful, were also seen this year compared to 2019, DPCC said.
“Of all the hot spots, Jahangirpuri, Ashok Vihar and Rohini recorded the worst air quality. The PM 10 values here crossed 1000 µg/m3, 10 times above the permissible limit. Besides, these three stations recorded the highest PM 2.5 concentrations with levels as high as 900 µg/m3. The levels peaked for around three hours at all the three hot spots,” the report said.
According to Indian standards, the 24-hour average permissible limits for PM 2.5 and PM 10 are 60µg/m3 and 100µg/m3, respectively.
Among the hot spots, the lowest PM 2.5 concentrations were found at Punjabi Bagh, Dwarka and Wazirpur while the lowest PM 10 concentrations were seen at Dwarka, Narela and Okhla, it said.
Delhi’s overall average PM 2.5 levels on Diwali this year were almost 20 times higher than the prescribed safe limit. The concentrations ranged from 274µg/m3 to 1131 µg/m3 as compared to last year’s 58 µg/m3 to 1070 µg/m3.
The PM 10 levels shot up by more than 14 times with the average concentration ranging from 392 µg/m3 to 1408 µg/m3. In 2019, it ranged between 149µg/m3 and 1391µg/m3.
“For both PM 10 and 2.5, the levels peaked at midnight for about three hours while the highest concentration for both was observed at Ashok Vihar. Here, the PM 2.5 levels spiked to 2939µg/m3 while PM 10 levels rose to 3320µg/m3,” the report said.
There was also a rise in the levels of noise pollution. “The noise levels were monitored at 26 locations. The noise levels ranged from 51 dB at Najafgarh to 81.5 dB at Jahangirpuri. On a normal day, the levels here range from 45.5 dB to 68.6dB,” it said.
But when compared to the past five years, the years 2017 and 2018 recorded worse air than in 2019 and 2020, the analysis says, without elaborating further.
The Central Pollution Control Board (CPCB) too in its Diwali pollution analysis earlier this month had said that the overall pollution levels this year were higher than last year.
The apex pollution watchdog attributed the high levels this year to bursting of firecrackers and a higher share of stubble burning coinciding with unfavourable meteorological conditions during the festival season.
According to CPCB’s analysis, the share of stubble burning in the city’s PM 2.5 levels this year was 32%, as compared to 19% last year.