With pollution this bad, it's getting dangerous for human survival. In 1952, London witnessed the danger of "The Killer Smog" that was made out of air pollution. Almost 4,000 people died and many more were ill. Mean while, 4,868 mi. away china is dumping chemicals into there rivers. Because of this the waters have turned yellow and green. Some people around the world are trying to clean up the mess, but it is proving to be easier said then done.