Geneva: Delhi is the most polluted city in the world when it comes to air quality, according to a WHO study released on Wednesday. In an effort to measure pollution in cities around the world the dirtiest air was found in Delhi, while Beijing’s measurements, like its skies, are far from clear.
The study of 1,600 cities found air pollution had worsened since a smaller survey in 2011, especially in poorer countries, putting city-dwellers at higher risk of cancer, stroke and heart disease.
Air pollution killed about 7 million people in 2012, making it the world’s single biggest environmental health risk, the WHO said last month.
Thirteen of the dirtiest 20 cities were Indian, with New Delhi, Patna, Gwalior and Raipur in the top four spots. New Delhi had an annual average of 153 micrograms of small particulates, known as PM2.5, per cubic metre.
Beijing, notorious for the smog that has prompted some Anglophone residents to dub it “Greyjing”, was in 77th place with a PM2.5 reading of 56, little over one-third of Delhi’s pollution level.
A year after it started publishing data, Beijing’s air quality hit the “worst on record” according to Greenpeace, with a PM2.5 reading as high as 900 on one occasion.
Maria Neira, WHO Director for Public Health, Environmental and Social Determinants of Health, said the aim was to “challenge” cities and help them become more open about their dirty air, which is often caused by burning coal, smokestack industries and heavy traffic.
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