Any answer other than ,"We do not know", is speculation.
The truth is ,yes , we are exposed to chemicals and dyes on a daily basis. Studies have been done on exposure limits to most chemicals (MSDS). Food dyes are GRAS for eating . Vaping is a whole other deal.
Fact :
We may inhale paint fumes . We do not vape them . Same goes for hair spray ,perfume , body spray, car exhaust and farts (unless of course someone has a fetish).
I just feel that your justification for it being ok to vape colors because we eat food coloring is misleading to those reading the forum. We all justify our own actions in life with reasoning . Sometimes our reasoning is logical . Other times , not so much. This is just an observation , not questioning nor judging your personal reasoning capabilities or choices . Most of us are vaping some food coloring. It is a chance we take . Until further studies are done, vaping flavors and food coloring is the big unknown .
In closing , Icon , you asked in the op if food coloring is safe to add to our liquids . The answer is still --- We don't know.