Delhi's air quality deteriorates to 'very poor' category, vehicular emissions leading contributor

File Photo/PTI

The air quality in Delhi remained at alarming levels, fluctuating between very poor and severe categories on Thursday due to unfavorable meteorological conditions impeding the dispersion of pollutants.

Recent findings from a collaborative initiative between the Delhi government and IIT-Kanpur revealed that vehicular emissions were the largest contributor, accounting for approximately 38 percent of the capital's air pollution on Wednesday. This figure is anticipated to rise to 40 percent on Thursday. The second major contributor was identified as secondary inorganic aerosols, comprising particles like sulfate and nitrate formed due to the interaction of gases and particulate pollutants from sources such as power plants, refineries, and vehicles, contributing 30 to 35 percent to the city's air pollution.

The accumulation of pollutants is exacerbated by calm winds and low temperatures, with no relief expected in the coming days, according to an official from the India Meteorological Department (IMD).

As of 9 am on Thursday, Delhi's Air Quality Index (AQI) stood at 393, categorized as very poor. The 24-hour average AQI recorded at 4 pm on Wednesday was 401. The situation has persisted despite stringent measures by the state government, including a ban on construction work and the entry of diesel-guzzling trucks into the city.

In Picture: Delhi shrouded in smog

Neighboring areas such as Ghaziabad, Gurugram, Greater Noida, Noida, and Faridabad also reported very poor to severe air quality, with AQI readings ranging from 325 to 409.

Delhi, identified as the most polluted city globally by Swiss air quality monitoring company IQAir, has been grappling with deteriorating air quality despite measures taken by the government. Stubble burning contributed to 23 percent of the air pollution on Wednesday and 11 percent on Thursday, according to a system developed by the Indian Institute of Tropical Meteorology.

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The Graded Response Action Plan (GRAP), the central government's air pollution control plan, is being rigorously implemented, including a ban on construction work and the entry of polluting trucks into the national capital. The odd-even car rationing scheme may also be implemented if the AQI crosses the 400 mark, as stated by Delhi Environment Minister Gopal Rai.

Prolonged exposure to such hazardous air quality levels can lead to severe health issues, equivalent to the harmful effects of smoking 10 cigarettes a day, according to medical experts. The situation is further exacerbated during winters due to unfavorable meteorological conditions and various local pollution sources. Stubble burning incidents in Punjab and Haryana contribute significantly to peak pollution levels in Delhi-NCR from November 1 to 15, according to the Delhi Pollution Control Committee. On Wednesday alone, 2,544 fresh stubble burning incidents were reported in Punjab, bringing the total number of such fires since September 15 to 30,661. A report by the Energy Policy Institute at the University of Chicago in August estimated that air pollution is reducing life expectancy in Delhi by almost 12 years. (With inputs from PTI)