Following Ludhiana with 209 micrograms per cubic meter is Kanpur, while Delhi ranks third with 198 and Lucknow and Indore with 186 and 174 micrograms per cubic meter PM10, respectively, round off the top five list.

Mumbai comes tenth with 132 micrograms per cubic meter of PM10 (particles less than 10 microns), according to World Health Organisation’s urban air pollution database released here on Monday. The database recorded PM presence in 1,100 cities in 91 countries of the world from 2003 to 2010.

India’s urban cities’ bad air is a far cry from WHO’s air quality guidelines of a maximum 20 micrograms per cubic meter but there are nine more cities in the country which have fared worse.

Incidentally, of the 32 cities in the country considered by the report, Amritsar is the least polluted with 41 micrograms per cubic meter.

Mumbai ranks third among metropolitan cities with the highest being Delhi and the lowest being Chennai with 48 micrograms per cubic meter. Kolkata came in second with 148 micrograms per cubic meter, while Bangalore was fourth with 90 micrograms per cubic meter.