Actually, this is quite interesting, because the flavourings are very much the argument of many anti-vaping brigade. Whilst there is a lot of evidence that inhaling PG and VG is regarded as mildly irritant to generally harmless, the flavours are, in the majority, the unknown quantity.
Of course, Flavour Art have a big ongoing project regarding the safety of their flavourings (or at least I think it is FA), but as many flavourings are primarily used as food flavours, there seems to be very little conclusive evidence for and against their use as vaping ingredients - aside from anecdotal evidence that very few people seem to be experiencing issues, but it is early days.
My personal view is that if they contain oil, and are known to contain oil, I won't touch them. Lipid pneumonia is something I don't want to experience - aside from that, I am largely relying on the experience of others to guide me. Of course, that, and my own personal experience of a massive increase in health since packing in the fags and picking up a vaping device. Very few flavours have caused me issues personally.
The only other thing I would say that if it is artificially coloured or gives me a headache on first vape, I avoid that too.
I think that asking suppliers of food flavourings to confirm that their products are safe for inhalation needs to be handled with a lot of caution, as discussions could easily be picked up, manipulated and ultimately used to reinforce the anti-vaping argument for why vaping must be regulated. But I may be Friday-afternoon paranoid!
I am not posting any of this to be confrontational, I promise.
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