America has been getting rid of its industrial base and as a result pollution will tend to decrease in America. Where does it all go? Other countries should know the bitter lessons of pollution should they not? Maybe yes and maybe no. Industry has gone to many other nations including China especially in the last decade. According to the People's Republic of China's own evaluation, two-thirds of the 338 cities for which air quality data are available are considered polluted. Respiratory, cancer and heart diseases related to air pollution are the leading cause of death in China. Meanwhile in Tehran, which is one of the most polluted cities of the world, there is a similar situation. Air pollution in the Iranian city of Tehran is not new. Ever since 1950 population and automobile ownership has risen dramatically.