Change:  the automobiles. Gases such as carbon dioxide, which contribute to global warming, have recently gained recognition as pollutants by some scientists. Others recognize the gas as being essential to life, and therefore incapable of being classed as a pollutant.brought to you by Wikipediawww.wikipedia.com   View changes from previous version. (Word count: 168)

Change: Created by gogreentheme Jun 13 2007, 8:54 PM EDT for: no reason given