Those are some grim statistics, but U.S. citizens shouldn't be so quick to castigate China. Evidence increasingly suggests that the U.S. is partly to blame for the uptick in Chinese pollution -- and, as a result, the poor air quality in Chinese cities. Current estimates say that between one quarter and one third of China's emissions are due specifically to the manufacture of goods for other countries. In other words, China generates pollution while manufacturing goods for the U.S., and ships some of that pollution back along with cell phones, game consoles and computers.