As many as 51 Indian cities have extremely high air pollution, Lucknow, Raipur, Faridabad and Ahmedabad topping the list.
An environment and forest ministry report, released Friday, has identified 51 cities that do not meet the prescribed Respirable Particulate Matter (RSPM) levels, specified under the National Ambient Air Quality Standards (NAAQS).
In 2005, an Environmental Sustainability Index (ESI) placed India at 101st position among 146 countries.
According to the report, Gobindgarh in Punjab is the most polluted city, and Ludhiana, Raipur and Lucknow hold the next three positions.
Faridabad on the outskirt of Delhi is the 10th most polluted city, followed by Agra, the city of Taj Mahal.
Ahmedabad is placed 12th, Indore 16th, Delhi 22nd, Kolkata 25th, Mumbai 40th, Hyderabad 44th and Bangalore stands at 46th in the list.
The Orissa town of Angul, home to National Aluminium Company (NALCO), is the 50th polluted city of the country.