To assess the level of pollution in Mumbai, nature and wildlife conservation magazine Sanctuary Asia’s founder Bittu Sahgal anchored an experiment in the city. Four popular means of conveyance in the city – local trains, motorcycles, buses, and cars were chosen to record the levels of particulate matter in the air that their passengers are exposed to.

“The measure of a good city is not to create citizens who aspire to drive cars but to create a city in which those who can afford a car would prefer to use public transport,” Sahgal says in the video, driving home the importance of a clean environment to live in. “Human body requires clean air far more than it requires clean food.”

According to the results of the experiment, train commuters breathe in 11% less pollution than a motorcyclist on the same route. Train commuters also breathe in 35% less pollution than BEST bus customers, but commuters travelling in AC cars breathe in 17% less pollution than people travelling in trains.

The video also suggests some immediate steps that must be taken to check the rise of pollution and its detrimental effects on human health: closed door/window buses with built-in air purification and circulation, and a time-bound shift to electric buses.