New Delhi, Nov 2 : Lahore has been declared the most polluted city in the world, leaving its traditional rival New Delhi far behind, Dawn reported. The official Air Quality Index (AQI) of Lahore was reported at 289 (as per the average between 9 a.m. and 5 p.m.) and international monitoring bodies put the score at 397. New Delhi stood at less than half of Lahore's pollution level, with 187. Individual areas of Lahore fared worse, with Kot Lakhpat (industrial area) crossing over 500, Fatehgarh housing most of the steel melting industry close to 400 and relatively green areas like Raiwind at 403 AQI. "At 397 AQI, , the pollution concentration is 34.8 times higher than the annual air quality value set by the World Health Organisation. This is, what environmentalists call, hazardous with it getting 'extremely hazardous' at individual points," explains Abdul Rauf, representing an organisation working on air quality of the city, the report said. "What makes the matter dangerous is that it was not smog on Monday, it was pure pollution," claims an official of the environment department. Smog occurs when smoke mixes with fog. On Monday, the humidity level in the city was 60 per cent Â? and such a level does not form fog. Monday's mist did not cause any eye irritation, which also proves it was not smog. This means that this haze was pure pollution. "Secondly, and what is extremely worrying as well, is the fact that it is purely indigenous. The country is still experiencing westerly winds, which means the wind is flowing towards India and pollution from that side of the border has still not invaded Pakistan. Once the wind changes its direction and carries Indian pollution (mainly smoke emanating from stubble burning) into Pakistan, the situation here would certainly worsen," the official said. /IANS