A pollution index by Numbeo, updated every week, is currently featuring four Indian cities in the 25 most polluted places in the world. In fact, the city of Lucknow takes the lead with the number one spot.

Lucknow is accompanied by Kolkata at 14 spot, closely followed by Meerut at 17, and Mumbai at 21. Interestingly, no other country features as many times on the list as India. “Pollution Index is an estimation of the overall pollution in the city. The biggest weight is given to air pollution, than to water pollution/ accessibility, two main pollution factors. Small weight is given to other pollution types,” states Numbeo, explaining how and what is calculated in this index.

“Lucknow faces many problems similar to major metros in India. So we can look at Lucknow as a test case for almost any other Class A or B city in India. Various independent and government research reports have conclusively shown that the ambient air quality in most part of the city is extremely poor – not only in industrial areas, but even in residential zones,” explains environmentalist and microbiologist Anuj Wankhede who has worked with Greenpeace and Société Générale de Surveillance.

And before you think, that perhaps India is simply having a bad week. Take a look at India's annual performance on the pollution index:

Lucknow still leads in the number one spot, followed by Mumbai on 8, and Kolkata on 11. And while China is in close competition on this list, we still take the crown with two cities in the top 10 most polluted.

What is being done?Not much. It is appalling that despite being the fifth largest killer in India, there is little movement to curb air pollution, or any other form of pollution for that matter.

Emphasising on the harmful effects of this situation, Wankhede adds, “The suspended particulate matter (SPM) levels are dangerously high and a cause of many chronic respiratory ailments. These ailments in turn can result in weakened immunity and secondary infections resulting in pain, economic loss and reduced productivity for the citizens. While large and small scale industrial units spew gases in an unregulated manner, the situation is worsened by the daily addition of vehicles onto the city roads.”

Also, in a stark contrast to India, China has been working on various policy initiatives to combat the rising pollution.