Of the 3 compounds that give many foods a smooth buttery taste (diacetyl, acetyl propionyl and acetoin) the first two are known to be irritating enough on inhalation to cause irreversible lung damage at a concentration estimated to be 20-100 times higher than what e-liquids highly flavored with them might vape at. This is a dismally inadequate margin, especially since illness was seen at buttered popcorn plants with average air concentration below that. These flavorings are used very widely, including wines and ciagarette tobacco, and if one compound is flagged or banned, the others are used. Thus disclosing use of diacetyl alone is not very useful. If all 3 are eliminated the food industry will develop new ones. Having Chinese materials safety lists (as one juice-mixer promised) doesn't count as complete disclosure for me, as Chinese industry was built on lies from A to Z, only a chemist can start to untangle any if it, and nobody knows what is toxic on inhalation. A juice-mixer can disclose very little that's relevant. Even if a flavor-maker discloses everything (about as likely as Chanel disclosing their scent recipes), they buy chemicals and "accords" they do not have full disclosure on. There's a hierarchy of secrets and there is money in keeping your upstream suppliers to yourself. Oh, and by the way, Chanel designed none of their fragrances, Roudnitska did, and they in turn don't know what's in the bases they buy in bulk.
But I believe more importantly this is our canary in a coal mine, as none of these food flavorings were intended for inhalation. So I have cut use of all the cute-bottled flavorings in my DIY dramatically to a "very subtle" level, in practice under 2.5% of total volume. In the process, i found that my feeling of fullness in the lungs and slight shortness of breath have tremendously improved.
By reviewing Flavourart's list of diacetyl-containing flavors I have marked all flavors that contain more than a trace of diacetyl, and all that resemble them, and completely avoided them, regardless of who makes them, and regardless of whether they claim to be "diacetyl-free", since they are likely to contain the substitutes. I'm personally not concerned about the ones that we know contain traces, I get probably as much buttering my toast, but I'm not using any vanilla custards, or yogurts, or apple pie, or wild mixed nuts, or coconut. All we can do beyond that is guess. Disclosure of percentage of all 3 of the "buttery" compounds in all flavors on the market would be nice.
There is a possibility that the third compound, acetoin, will not show this same extent of toxicity when results of the NIH acute toxicology study are published. If acetoin at 300 ppm can be breathed by rats and mice for over 8 hours a day without sign of nasal or bronchial (or lung!) tissue necrosis or apoptosis, then acetoin might turn out to be usable as an acceptable substitute, and the alert level on the issue might de-escalate with regard to vaping as well, as long as all diacetyl AND acetyl propionyl are eliminated from flavoring.
However if acetoin is no better than the other 2, then the food industry will desperately synthesize substitutes that will not necessarily be tested for vape-like inhalation toxicity and the musical chairs will become even more dangerous.
I rather expect that many of the esters, aldehydes and ketones that give natural and artificial flavor, when tested will turn out to be highly irritating to delicate respiratory tissues at higher concentration, and simply cannot be inhaled with impunity. [I do think that] until we can identify or design molecules that are safer in this role, we should use as little flavoring as possible all around. I'm very fond of strong and sweet thick rich flavors, it's a bit of gluttony, but it seems that my lungs feel better with light flavoring, my sensing has compensated so I can now enjoy much more subtle flavoring, and it's just not worth vaping loads of additional chemicals when even unflavored glycerin & propylene glycol & nicotine taste fine, and a touch of menthol or fruity aroma turns it into a feast. I hope that answers your question, edwv30.
But I believe more importantly this is our canary in a coal mine, as none of these food flavorings were intended for inhalation. So I have cut use of all the cute-bottled flavorings in my DIY dramatically to a "very subtle" level, in practice under 2.5% of total volume. In the process, i found that my feeling of fullness in the lungs and slight shortness of breath have tremendously improved.
By reviewing Flavourart's list of diacetyl-containing flavors I have marked all flavors that contain more than a trace of diacetyl, and all that resemble them, and completely avoided them, regardless of who makes them, and regardless of whether they claim to be "diacetyl-free", since they are likely to contain the substitutes. I'm personally not concerned about the ones that we know contain traces, I get probably as much buttering my toast, but I'm not using any vanilla custards, or yogurts, or apple pie, or wild mixed nuts, or coconut. All we can do beyond that is guess. Disclosure of percentage of all 3 of the "buttery" compounds in all flavors on the market would be nice.
There is a possibility that the third compound, acetoin, will not show this same extent of toxicity when results of the NIH acute toxicology study are published. If acetoin at 300 ppm can be breathed by rats and mice for over 8 hours a day without sign of nasal or bronchial (or lung!) tissue necrosis or apoptosis, then acetoin might turn out to be usable as an acceptable substitute, and the alert level on the issue might de-escalate with regard to vaping as well, as long as all diacetyl AND acetyl propionyl are eliminated from flavoring.
However if acetoin is no better than the other 2, then the food industry will desperately synthesize substitutes that will not necessarily be tested for vape-like inhalation toxicity and the musical chairs will become even more dangerous.
I rather expect that many of the esters, aldehydes and ketones that give natural and artificial flavor, when tested will turn out to be highly irritating to delicate respiratory tissues at higher concentration, and simply cannot be inhaled with impunity. [I do think that] until we can identify or design molecules that are safer in this role, we should use as little flavoring as possible all around. I'm very fond of strong and sweet thick rich flavors, it's a bit of gluttony, but it seems that my lungs feel better with light flavoring, my sensing has compensated so I can now enjoy much more subtle flavoring, and it's just not worth vaping loads of additional chemicals when even unflavored glycerin & propylene glycol & nicotine taste fine, and a touch of menthol or fruity aroma turns it into a feast. I hope that answers your question, edwv30.
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