The chemical industry has made many contributions to humanity's quality of life, as can be seen, for example, in the histories of chemists who invented processes to extract aluminum from the earth and gases from the air and who created new substances of all kinds, including those that make possible modern electronic communications and life-saving pharmaceuticals. The industry has also created problems that demand solutions, and scientists have in the past alerted the public to these dangers and proposed appropriate solutions. In the future chemistry and chemical engineering will strive to create new processes that do not cause environmental problems.