The town has a sad record: is the most polluted city air around the world, is so designated in 2007, a report by the Blacksmith Institute, an American organization specializing in projects relating to pollution control. Surrounded by coal mines and power plants using coal as an energy source throughout, Linfen - the city with over four million inhabitants - is a chronic black smoke choked the darkened sky. They say that if you dry your clothes outside, you have no chance to get cl...