Since you are the one making the claim that dust is causing B.O., the burden of proof is on you to show documentation stating this. I am not making the distinction, you are ! I showed you an article that clearly stated "liquid" is used, and you came back with some nonsense about coffee grinding ! Now show me one study that implicated "dust" as the cause for B.O or that makes a distinction between different forms of diacetyl ( powder or liquid ) as far as potential causes of lung disease.
Thanks
@crxess for the info.
I have read most if not all the government literature concerning their studies about what happened
in the plants. Nowhere do they specifically state what form of diacetyl was used nor when any
specific form was used more than any other. Many of the studies just referred to diacetyl leaving
the reader to speculate what form was used. From personal experience I know dry bulk raw material
is cheaper to package and ship and a likely first choice unless other factors come into play.
Further the studies are none to clear about the processes going on and when they are occurring.
Generally and oil (primarily soy bean) is heated in a vat where the flavorings and all other necessary
ingredients are mixed together. When ready this is added to the kernels.
When the government did simulated testing of all three forms they placed them in sealed test tubes
and heated them quickly to 50C (122F). They found the highest ppm of diacetyl in air from the liquid form,
then the paste,the powdered being the lowest. This makes sense in a test tube. However they fail to
explain which process occurring at the plants these where simulating and or what plants these had occurred.
The only hint one can find is the reference about the powder becoming a dust born contaminant during
the mixing process. Note the government never tested the three forms of diacetyl after already being
blended into the final product. So where was the exposure coming from? Liquids in ambient air disperse and
dissipate very quickly generally. Dust not so much. Dust also will collect. It gets tracked all over the production
area.
Considering the links from two Universities with distinguished medical facilities I posted consider popcorn lung
an airborne dust related disease I will consider it dust related until proven otherwise. Dust will stick to your
lungs. Liquids unless causing an immediate chemical reaction that is causing harm should in most cases flush
out of your system. The dust makes sense.
There are ZERO studies that say with certainty that vaping is 100% safe , is vaping better than smoking i don't think anyone can deny that but completely safe , don't think so .
As to your second comment , you know very well that cannot be proven , so your saying it's a fact that diketones (without question) have absolutely nothing to do and are not a contributor in any way to any disease where smoking is to blame , OK man , hopeless, truly hopeless.
There are studies that say vaping is 100% safe. These primarily are for the PG and nicotine.
There are many other studies indicating that overall vaping is anywhere from 95% to 99.9 %
safer than smoking. When the studies are averaged out it comes to around 98.7% safer.
What you fail to realize is in the real world where nothing can be said to be 100% safe
there comes a point where the chances for harm are so low that no harm may occur at all
and if in fact it did it would be impossible to prove what actually caused the harm.
The sample rate would be to low. So for real world scenario's one could say,yes its safe
as anything could be. You can use the word safe! You do not have to allude to the possibility
of harm when that possibility has no quantifiable meaning.
Regards
Mike
at this point 
