Yes ... However. Most ecigarettes and liquids used in nicotine vaporizers do NOT contain tobacco products. The Risk is in the Flavor used. FLAVORLESS nicotine liquid contains only two ingredients -- glycerin and nicotine. Tobacco contains over 4000 other compounds including over 70 well-known carcinogens. While nicotine alone may be relatively safe, the rest of tobacco smoke is definitely NOT.
I have no clue. and actually, at this moment, nobody other than people in the company that makes them would really know the answer. The ingredients in e-cigs are trade secrets, and do not have to be revealed to any government authority. The FDA has put out regulations that, if approved (unlikely, I think) would force companies to put out that info so studies could be done. But currently, buyer beware!