So all those saying that it’s harmless and it’s just the smell that folks unreasonably object too, presumably you are OK with a colleague dropping his guts next to your desk or belching in close proximity? No harmful effects, just a bad smell. Or maybe basic consideration for fellow human beings has a bearing.

The problem is your dealing with ex smokers who just like to feel persecuted. Everything is just so unfair man….
AFAIK the content is still unregulated and you can make your own liquid to use so studies of the branded stuff may not apply to what’s being used.

But put simply it’s not allowed in this office and the guy knows it. He is taking the piss.