New Delhi tops WHO's most polluted mega-cities in the world list

While there were concerns of pollution in Chinese cities such as Beijing, the pollution levels seems much lower in comparison to Indian cities. New Delhi is the most polluted mega-city in the world, according to data from the World Health Organisation (WHO).

Source: WHO, Leslie Josephs, Quartz

New Delhi has 229 micron particle pollution per cubic metre. The closest to it is Cairo in Egypt was has 179 micron particle pollution per cubic meter.

Air pollution levels of 10-micron particle pollution per cubic meter is the permissible level set by WHO.

Besides New Delhi, other Indian cities such as Kolkata and Mumbai also feature in the most polluted mega cities list. While Kolkata is at 4th spot with 135 micron particle pollution per cubic meter, Mumbai comes next on the list with 117 micron particle pollution per cubic meter.

In third spot is the capital of Bangladesh, Dhaka which was 158 micron particle pollution per cubic meter.

China's capital Beijing is in sixth spot after Mumbai with an air pollution level of 108 micron particle pollution per cubic meter. It is followed by another Chinese city Shanghai with 84 micron particle pollution per cubic meter.

They are followed by mega-cities such as Istanbul in Turkey, Mexico City in Mexico, Sao Paulo in Brazil and Buenos Aires in Argentina.