In January this year, a report estimated that air pollution kills 1.2 million Indians each year and takes 3 percent off the country’s Gross Domestic Product (GDP). The levels of the most dangerous airborne pollutants grew by 13 percent in India between 2010 and 2015, the report by environmental NGO Greenpeace added.

The fact that air pollution is now a real threat has also been corroborated by industry bodies such as the Confederation of Indian Industry (CII). At a recent conference in New Delhi, it stated that 10 Indian cities are among the top 20 most polluted cities in the world and these include Ludhiana and nearby Khanna in Punjab. Rapid urbanisation has been cited as one of the key drivers of air pollution.

To address this growing threat, researchers from the University of Chicago, Harvard University and Yale University worked with the Maharashtra Pollution Control Board (MPCB) to launch the first-of-its-kind five-star rating system in India to measure pollution.