Delhi is world’s most polluted city; 90% world population is breathing polluted air

Delhi is world’s most polluted city and Mumbai is fourth, according to air quality data compiled by the World Health Organisation (WHO)  for megacities with a population of 14 million or more.

Globally, air pollution levels remain dangerously high in many parts of the world.
New data from WHO shows that 9 out of 10 people breathe air containing high levels of pollutants. Updated estimations reveal an alarming death toll of 7 million people every year caused by ambient (outdoor) and household air pollution.
In general, ambient air pollution levels are lowest in high-income countries, particularly in Europe, the Americas and the Western Pacific.In cities of high-income countries in Europe, air pollution has been shown to lower average life expectancy by anywhere between 2 and 24 months, depending on pollution levels (source).