It is a bit of a stretch to say there are no oils involved whatsoever. Glycerol/glycerin is almost always produced from triglycerides such as vegetable oil. (Ed

It is a bit of a stretch to say there are no oils involved whatsoever. Glycerol/glycerin is almost always produced from triglycerides such as vegetable oil. (Edit: as the article states, the potential for left over oil from this process being present in the glycerol is one of the causes being explored) Additionally, I believe the flashpoint for glycerol is lower than most vegetable oils so your argument doesn't make sense.