Delhi has the dirtiest air in the world: WHO

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Delhi is polluted. No doubt. However, Its really a revelation to know that it has the most polluted air in the world. A WHO report, quantifying the levels of air pollution in 1600 cities of 91 countries across the world, makes it official. 

Inhospitable India

  • India is home to top 4 most air polluted cities in the world namely New Delhi, Patna, Gwalior and Raipur respectively as per a report by WHO.  
  • The study finds top 20 dirtiest cities to be Indian.
  • The lethal New Delhi had an annual average of 153 micrograms of small particulates (the most worldover), known as PM2.5, per cubic metre.
  • Delhi's reading was almost three times that of Beijing 59.

Points to Remember

  • The alarming and consistent rise in air pollution has especially engulfed the growing cities of developing world, putting city-dwellers at higher risk of cancer, stroke and heart disease.
  • Air pollution has killed about seven million people in 2012, making it the world's single biggest environmental health risk.
  • Some 80 percent of those deaths came from heart attacks and strokes.


  • Air quality is represented by annual mean concentration of fine particulate matter (PM10 and PM2.5,– particles smaller than 10 or 2.5 microns).
  • The database covers the period from 2008 to 2013, with the majority of values for the years 2011 and 2012.

The Cause for Concern

  • Coal fired power plants, 
  • Rising use of automobiles
  • Use of biomass for cooking and heating
  • Inefficient use of energy in buildings

Does it paint a clear picture?

  • There are many in India, particularly government officials, who are not buying the findings.
  • The report is based on Chinese data from 2010, and the pollution levels have grown manifold since then. 
  • WHO was unable to collect data from most of the world's cities like for example only six African cities featured in the analysis.
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