Reports said that in the past 72 hours the Air Quality Index (AQI) in Kolkata dipped to the 'very poor' category.
The Indian Expressreported that according to the National Air Quality Index (AQI) website, PM 2.5 count at Rabindra Bharti University, one of the two stations in the city, was in the 'very poor' category at 381 on Thursday, while Delhi's Ashok Vihar the AQI was at 292.25.
A high number for diesel vehicles and policy inaction seem to have worsened the city's air pollution problem.
On Monday morning, the AQI showed Ashok Vihar at 356 and Rabindra Bharti University at 342.
The Express report compared the air quality in both the cities from Friday to Sunday and Kolkata's air quality was worse most of the time.
The Times of Indiaquoted auto emission expert Somendra Mohan Ghosh as saying, "While Delhi goes with odd-even experiment, Kolkata has chosen to sit tight and ignore the issue. Worse, it has over the years turned into a diesel vehicle capital with more vehicles running on the fuel that is dirtier than petrol."
Unlike Delhi where most public transport runs on CNG, most public transport in Kolkata, especially buses, run on diesel.