Where's the Objective Scientific Evidence for the Dangers of Diacetyl and Acetyl Propionyl?

I came across a blog called vapemestoopid.co.  In particular this post stands out:

http://vapemestoopid.co/2015/06/cloud-9-removes-five-pawns-testing-results-pending-legal-advice/

Basically its a discussion about how a UK lab and company called Cloud9 tested an e-liquid called Five Pawns.

The crux of the article is a table that shows the following data:

vapemestoopid says: "Five Pawns told more than one company in the UK that their liquids were DIACETYL and AP FREE. Not to mention how many in the US? Not to mention numerous email replies to consumers found during a simple google search. Dating back to 2013 from US, Australia and Greece."

vapmestoopid supplies the following three images (copied from their blog - link above):

So here we see Five Pawns claiming no Diacetyl or acetone.  Now acetone is not Acetyl Propionyl (AP) - a miss spelling?  Perhaps, but by how - its all greek to me...

And here we see Five Pawns claiming no Diacetyl - no mention of AP.

And here is some hearsay from GrannyGrump.

So as best I can tell Five Pawns claims not to use Diacetyl - nothing about AP anywhere except in the mind of vapemestoopid...

Not surprisingly Five Pawns claims the Cloud9 results are baloney:

http://fivepawns.com/five-pawns-test-results/

Here is the summary of Five Pawn's latest test numbers:

All but "Perpetual Check" have no detectable diacetyl according to their lab.

However, they do test positive in a number of flavors for 2,3 Pentadedione (AP).

What's interesting is the AP results all seem off by about a factor of between three and five.

So the conclusion of vapemestoopid and Cloud9 is apparently that e-liquids with "high" levels are dangerous because of this study, among others.

Indeed the referenced study cites other well known studies that have appeared elsewhere here and on Facebook and various vaping sites.  However this document also says things like:

"Regarding the combination of flavorings with propylene glycol and glycerin in aerosols, specific concerns exist for lung and cardiovascular function: 1) propylene glycol or glycerin alone may elicit pathophysiological and/or pathological changes in lung function; and 2) interactions between the effects of the individual agents may heighten toxicity."

Effectively all flavors and PG and VG might be bad in some way, also nicotine, for you to inhale.

The bottom line here seems to be that, "OMG, vaping certain flavors might be bad!"

So some arbitrary flavors are picked out - diacetyl and a variant of it, AP.

Why these?  They relate to the infamous "pop corn lung" incidents.

See: http://lwgat.blogspot.com/2015/02/diacytel-real-cause-of-health-problems.html

Also: http://lwgat.blogspot.com/2014/05/diacetyl-whats-real-objective-danger.html

Please read these.  The bottom line is no one, not the FDA or the CDC, has any real idea what happened with these incidents.

So I think a couple of things:

1) Running around testing e-liquid and publishing results without documenting the process in specific detail seems stoopid.  For example, the UK lab (according to Cloud9 uses "[the] same independant UK-based lab used by Trading Standards." - whatever that might mean) and the US labs, one would hope, would express how they do their work and how they calibrate and handle their processes, samples and equipment.

In addition one would hope that multiple samples and multiple labs would be used in a double blind study to ensure that both properly calibrated test samples as well as commercial samples are effectively intermixed during testing.

(This kind of testing is what a vaping trade association should do. My suspicion is that many are duped into paying money for bogus processes and results.)

2) The problem, as stated here on this blog as well as in the Five Pawns blog is this: "Further, we feel that efforts to translate industrial exposure limits to vaping exposure limits are flawed. It is clearly not the same.  If this were true, one would expect a population of individuals becoming sick from vaping, but this is not the case (underline mine). There are no known publicly documented cases of anyone having respiratory issues related to vaping AP or diacetyl at the levels currently in e-liquids.  Many websites and blogs discuss this exact issue.  We are confident that studies and future data will show inhalation from vaping e-liquids should not be compared to industrial exposure limits." - basically there has to be a reason vaping and smoking are not killing people due to DA or AP.

Until this issue is scientifically vetted panicking and screaming "Danger Danger" about DA and AP is really scientifically bogus and very misleading for consumers.

Is there a risk? Of course.  There is risk in breathing and in smoking.  Is smoking a greater risk than vaping?  Is it in the best interest of the consumer to continue smoking until, decades from now, all this is resolved?

No.

3) Testing results for DA and PA can and do vary over the life of an e-liquid bottle (again from the Five Pawns blog): "We have funded extensive independent research, including inhalation and heat studies, and have plans to begin in-vitro research as well, looking at the effects of e-liquid vapor on lung tissue.  In our research, we have also discovered that the effects of storage conditions and time on the shelf can also affect the variability of test results (underline mine).  Therefore, we have also initiated long-term stability and degradation testing, which can take up to two years for results."

So testing not only has to be calibrated relative to amounts but it must be applied comparably across testing environments and samples relative to the "age" of the liquid, exactly how the testing is done, and so on.

4) There are many other questionable ingredients like cinnamon which no one seems concerned with yet are demonstrably and objectively "worse" than DA or AP in terms observable of impact on body tissues in humans.  Selecting a small subset of some of these flavors (like DA and AP) but not others is also very misleading for consumers.  Yet I see no hew and cry for their removal from e-liquids.

The bottom line here is really simple:

Cigarettes are known to be significantly more dangerous than virtually all forms of vaping at this time.

DA is already in cigarettes (and vaping for that matter) at comparable levels to the "panic" levels described by vapemestoopid and clould9 yet apparently neither causes OB.

Without an scientific explanation of this fact its really disingenuous to make claims DA or AP are dangerous.

One must also consider the danger of leaving people on cigarettes until the "safety" of vaping is confirmed.

This is like telling children to wait in the burning second floor room until a proper, government approved ladder is available to rescue them.

Panic mongering is not good for anyone...