Of the world's top 20 polluted cities, 13 are in India compared to just three in China. Since 2000, though Beijing's air pollution has dipped by 40%, in India Delhi's air pollution has steadily climbed by 20% in the same period.According to Central Pollution Control Board, during early morning hours when humidity level is high, PM levels are above 500 while during the day time, they usually hover around 250-300. The safe limit of PM 10 is 100µg/m³ and PM 2.5 is 60µg/m³, which shows that Delhi on Monday witnessed nearly 8x of the most hazardous components of air pollution.Additionally, rise in air pollution post Diwali is a common phenomenon. "She further adds that with no winds, crop burning and dropping temperatures, air is trapped which has created an emergency-like situation, especially in Gurgaon.Urging for schools to be shut at this point of time, Asthmatic patient Namita says that Delhiites should strictly avoid exercises and stay indoors with air purifiers. A Lancet study in 2012, ranked air pollution as the sixth biggest killer with an annual estimated toll of 66 million and over these last four years the numbers have undoubtedly increased.

Source: Economic Times November 04, 2016 07:26 UTC