Based on some ideas raised in a different thread. So called "e-cigarettes" are often billed as the safe alternative to real cigarettes (besides the other alternative, quitting). Frequently it is claimed that what is produced by the e-cigarette and exhaled is just water vapor. Usually there's a heating element that creates vapor from a solution of nicotine and/or various flavor additives. According to a peer-reviewed study by Goniewicz et al in Tobacco Control (published by BMJ in 2013), e-cigarette vapors contain from 9-450 times lower levels of 11 toxicants also found in real cigarettes ranging from carbonyls, metals, VOCs and nitrosamines. One potentially biasing factor is that different smokers use e-cigarettes differently. Some may purposely inhale a lot to get a bigger exposure while others may use their cigarettes more conservatively and not get much exposure at all. The authors of the study compared 15 1.8-second puffs of an e-cigarette to a whole conventional cigarette to make their claims about toxicant levels. (Believe it or not the methods of generating exposure amounts to make claims about how much of a certain toxicant is found in cigarette smoke is the subject of intense debate for as long as I have known people were studying it.) Further, flavor additives in some e-cigarette products are being reviewed by scientists and health officials because they may pose their own unique health hazards. With this in mind, should people who use e-cigarettes ("e-smokers"? I think I've heard "vapers" too) be allowed to smoke indoors? It is fairly commonplace where I live to see someone do this at restaurants, theatre lobbies and especially of course bars (even if non-smoking). I have yet to see someone openly complain about it. I don't have a strong opinion either way at this point in time, although I am highly suspicious of the flavored e-cigarettes as their health effects are very poorly understood at this time. On the other hand plain e-cigarettes would appear on first glance to pollute their environment and their consumer far less than traditional cigarettes. Discuss.