Just a note: There is full disclosure on the Flavor express line that it is made in China (it is on the flavor description page). [...]
Just to be clear, ECX's flavor line for tobacco flavors at least, is called Tobacco Express, not Flavor Express (just in case a "Flavor Express" line exists somewhere). And one more point of clarification... as far as Tobacco Express goes, the flavors are from all over, not just China. Some are made in USA. But as it states in the OP, ECX has no idea if ANY of their flavors contain these chems and in fact they assume some if not many do.
And yes, that was MY mistake that I didn't scroll down the page far enough to see the DJ RUM flavor was made in China, as that was another bad assumption on my part, that *respected* US vendors (as I felt ECX was), would not use China, and I had viewed some of their other flavors that happened to be USA-made.
As to FlavourtArt not revealing acetonin, do you have a link? I find that significant.
IAC I have been vaping 3+ years and have always used TFA for all of these reasons. (Just don't like their tobacco flavors, which is why I ventured out to ECX.) TFA isn't perfect but they have tried to stay current and be forthcoming about diacetyl, acetonin and A/P as info comes to light about these chems. Some things can be confusing... like their dicacetyl-free formulas are prefixed by a "DX" e.g. "DX Banana Cream" .... but after they made those, the concerns about acetonin and AP came to light... so while DX flavors are ALL dicetyl-free, some have acetonin or AP (others don't) but where acetonin or AP are present, TFA notes it for customers. And for that they have kept my business over the years. Even if I decide to use flavors with these chems, I want to know which flavors don't have them. Buyers can then make an informed decision rather than the vendor making it for them.
To this end TFA has also revealed that the chem used for buttery notes, when not diacetyl's replacements of acetonin or AP, is butyric acid. And this was posted on their site in July 2014 about that:
"There is another custard note that has not had as much attention as the others, and that ingredient is Butyric Acid. Butyric acid is found naturally in butter and milk, as well as certain cheeses, and it is sometimes used at low levels to accentuate a butter note. It is not as commonly used at as high levels as Acetoin and Acetyl Propionyl, because if overdone it can lend a rather unpleasant aftertaste to a flavor. There are companies who are now using it more in place of Acetoin and Acetyl Propionyl, but in reality Butyric Acid can also be irritating when inhaled." (
http://shop.perfumersapprentice.com/flavorsworkshop/custard.html)
Reading this [last year] DID make me wonder if just vaping diacetyl isn't better than the stuff used to replace it... which might surprise mgmrick to hear me say. In the meantime though, until more research is done that ends the controversy once and for all, I do maintain vendors have an obligation to the public to provide information on these chems so that the buyer can make an informed decision. There is no 'right' or 'wrong' answer when it comes to freedom of choice. But without info, there is no choice available.