LAHORE: Bad air keeps Lahore ranked second in the most polluted cities of the world with AQI reading 396 on Saturday, ARY News reported.The air quality in various parts of Punjab remains extremely hazardous according to reports.Faisalabad remained the most polluted city in Pakistan with 571 reading on the air quality index. Gujranwala remained second in the country with 570 level of the particulate matter.Lahore’s air quality reading remained 396, while Multan’s AQI reading counted 257 on the index.Last year air pollution and smog haunted Punjab with the onset of winter. Authorities made desperate efforts to contain smog in cities. The province grappled with severe air pollution, which soared to alarming levels, causing serious public health issues.For days, Lahore was enveloped by smog, a mix of fog and pollutants, caused by low-grade diesel fumes, smoke from seasonal agricultural burning as temperatures drop with cooling air.Air pollution level in Lahore once soared to more than 80 times of the level deemed hygienic by the World Health Organization (WHO).The government closed schools and restricted timing of eateries, other businesses and markets to save general public from the adverse impact of toxic pollution and health problems.