A first of its kind pan-India study has highlighted Mumbai and Pune as among hotspots in the country, where high air pollution from transport and industrial sectors has a visible relationship with higher number of Covid cases and casualties. The study has been conducted by experts from Utkal university in Bhubaneswar, Indian Institute of Tropical Meteorology in Pune, National Institute of Technology in Rourkela and IIT-Bhubaneswar.