I have been passively smoking e-cigarettes for a few months now (low nicotine level). And I have not noticed any major difference in my health or performance. I have never been a smoker by the way, it was just uni pressure that led me to start.
Obviously it is too early to know now but the debate is heated around the possible health risks associated with it.
Some say its a horrible chemical potion whits other argue that it is 100x better than the conventional tobacco based products.
I am honestly of the opinion that is is better than smoking tobacco but obviously like anything in life, moderation is key.
Would be great to get opinions on this!
Feel free to comment.
kamakawida 
Interesting experiment although I really don’t have any insight as I quite smoking tobacco 10 year ago.
Thank you for your reply. Yes its a experiment in progress so lets see how it goes. I will try quitting at some point too.
Very impressive that you managed to quite, I have many friends who have tried and failed (family included).