New Delhi has earned the title of being the world’s most polluted capital for the third year in a row.
IQAir, a Swiss group that measures air quality levels based on the concentration of PM2.5, placed the Indian capital over 106 capitals of the world for the year 2020. In fact, 35 of the world’s 50 most polluted cities are in India, the 2020 IQAir World Air Quality Report stated.
PM2.5 (particulate matter) is airborne with less than 2.5 microns in diameter. Extended exposure to PM2.5 can result in cancer and heart ailments.
In 2020, New Delhi’s average annual concentration of PM2.5 in a cubic meter of air was 84.1 — double that of Beijing. The report further states that air pollution resulted in 54,000 premature deaths in the national capital in the same year.
A nationwide lockdown imposed in March last-April last year didn’t help much as India still remained the world’s third most polluted country after Bangladesh and Pakistan. During this period, Delhi’s PM2.5 concentration came down by 11%.
While the summer was comparatively cleaner for Delhi, thanks to the pandemic-induced lockdown, the winter chill brought back smog (smoke+fog), a direct result of stubble burning in farms of Punjab, Haryana and Uttar Pradesh.
The 2020 IQAir World Air Quality Report stated that at the peak of the stubble burning period, Delhi’s PM2.5 levels averaged 144 micrograms per cubic metre in November and later rose to 157 micrograms per cubic metre in December – way beyond the World Health Organisation’s annual exposure guideline.