Ironically, the major ingredient that could potentially be 'harmful or failed' is' certain flavours; in particular, those that contain custard notes such as diacetyl however despite this, any possible harm is lower limit of smoking from mere graduations.
Ironically, the major ingredient that could potentially be harmful is that of certain concentrated flavours; in particular, those that contain custard notes such as Diacetyl. Notwithstanding this, any possible harm is magnitudes lower than that of smoking.