Cigarettes contain over 4000 chemicals which are exhaled and released into the air and the atmosphere. Approximately 30% of North Americans are smokers, and the percentage goes much higher in developing countries, which means there is a massive amount of pollution being released into the air every day. Trees are often compared to the lungs in our bodies because they perform basically the same functions as our lungs do on a global scale. With all of the pollutants that the trees filter out for us already it seems almost crazy to add more to the air that doesnt need to be added. We need to breathe, but no one needs to smoke. Not as common. People who love them and the environment.