Electronic cigarettes, also called “e-cigarettes,” are battery-operated devices that generally contain cartridges filled with nicotine, flavor and other chemicals. The electronic cigarette turns nicotine, which is highly addictive, and other chemicals into a vapor that is inhaled by the user.
Source: FDA
Hmm...From everything I've read, there has not been any credible scientific evidence that shows these products are safe for human consumption. In fact, there isn't anything that shows they will help smokers quit. In addition, they still deliver nicotine, which is highly addictive. How can we say something is safe without quality, credible scientific studies?
I thought this article was great in provided additional information. http://www.tobaccofreekids.org/Script/DisplayPressRelease.php3?Display=1166
Great work FDA!