Oxygen

This is what we breathe in. But what is the purity of it? If people from 100 years ago lived today in the cities they lived then would they have breathing problems? I remember from the Beijing games athletes were being sent back home because they were having breathing difficulties. When I watched the men's beach volleyball team (which was awesome! we won the gold!) they were sweating ridiculously. They had to take out their lenses from their sunglasses because of the humidity but left the frames in because of sponsor issues. They were able to adapt! Or were quite creative in fixing their problem because they were there to fight for their Olympic dream. So does that mean the people of China have adapted to the air they breathe. I would believe a lot people would naturally have asthma problems and the air pollution would increase it otherwise. I read somewhere that Beijing had to close many of their factories 6 months before the games begin to reduce some of the '"air pollution". I wonder how much difference it would make if the U.S. shut down part of its factories...or maybe even the ones that NAFTA created. hm....