While I don't smoke and I think cigarette smoking is really gross, vaping and the popcorn lung situation is pretty serious to me. It's like COPD on steroids. I also don't like that you can't smell it in a bunch of them unless they are flavored (from my experience at least, again I don't vape or smoke). I do see it as an improvement over cigarettes of course though.
Popcorn lung situation?