E-cigs, vaporizers, etc are still very new. There have not been any studies on their affect yet. It is not known at this time what exactly the effects of these fad items are and what they are doing to the "inhaler".
I believe that in about 10 years (maybe less) they are going to find that they have all of the same side effects as tobacco. You are still inhaling nicotine.....and whatever else is in them.