There was this study fairly recently, dunno if the others posting responses are unaware of this or are purposefully hiding it, but this study does say there seems to be dangers of the toxic heavy metals used for the coils burning off with the PG/VG concentrate and entering the lungs, which to me seems like a concern.

The study seems to have been funded by a slew of anti-smoking groups though, so take it with a grain of salt.

Just for the record, I don't vape but my SO does, I quit nicotine years ago. So yeah, also not a bot or shill.