I'm sorry Seabrook, I really don't remember where I read that about coconut. It may have been something someone posted on ECF or elsewhere. It was not an article or study AFAIK - Just one or two sentences giving caution. I'm not even sure how credible it was, but figured I would ask Linda while I was asking about the other more obvious candidates. As I said, I could see some flavorist wanting to give a more creamy taste to it by adding some - so it's possible.
Yes I read about various fruits containing diacetyl. AFAIK, it is in much smaller amounts than in dairy flavorings. The questions are how much, if any, actually makes it through to the flavoring from the extraction or distillation process? What exactly is the threshold concentration which leads to health problems? Is it a necessary ingredient for giving a true taste of the fruit since it is present in very small amounts (compared to dairy flavors)?
I don't know that any of these questions have been definitively answered yet. I ask the last question because I'm pretty sure that when extracting butter flavor they make sure that as much diacetyl as possible is retained to give it the desired flavor. I'm not sure that this is the case for fruit flavors so it's possible that only negligible amounts or even none makes it through to the flavoring depending on the process used.
Thanks for the info on peanuts. I didn't know that. Again, those aflatoxins may or may not make through to the flavoring, and even if present, we don't know if vaping them has the same effect.
I'm not going to worry too much about the unknowns. The worry might be more deleterious than the effect of the unknown. But as I sit here typing this I am vaping unflavored juice with a few drops of Lung Tonic tincture from Herbs ETC mixed in (which I use in all my liquids).

I vape unflavored at times as a break in between flavors. I also think it helps make my attys and cartos last longer before needing a cleaning as the flavorings are the primary culprit for gunking the coils.