Lahore, Nov 30 : Lahore has again topped the list of the most polluted city in the world, according to air pollution data released by the US Air Quality Index on Monday. According to the index, Lahore reported a particulate matter (PM) rating of 423, reports Geo TV. Lahore is not the only Pakistani city to feature in the top 10 list for the worst air quality. Pakistan's largest city of Karachi ranked at 7 on the AQI. Lahore's AQI fell in the range of 301 and higher, which has been classified as "hazardous". To reduce the smog, the Provincial Disaster Management Authority (PDMA) in Punjab has to date sealed 613 brick kilns, 2,148 industries and impounded 8,579 vehicles. The PDMA has also arrested 478 people. In the list, New Delhi ranked second with a PM of 229, while Kathmandu was the third-worst city with a PM of 178. /IANS