Confused about diacetyl? You should be

Toxic tort attorney Tom Burcham shares insight into diacetyl, popcorn lung, vaping, inhalation in factories, and how this creates major lung damage.

Below is an article discussing diacetyl and acetyl propionyl. While the focus of the article is on vaping, the discussion on factory workers is who inhale diacetyl daily is key.  Depending on an individual you may have symptoms within months while others develop them after years of exposure. Inhaling this toxic chemical is dangerous.  If you have worked in a factory with this chemical and have inhaled it you need to contact Tom Burcham today, you may be eligible for monetary compensation.  Call Tom at 573-756-5014 or email him via the online form.

Two prominent Vapestore businesses have recently removed from sale e-liquids they have found to contain “unacceptable levels” of diacetyl and or acetyl propionyl (DA/AP).

This really is the e-cig industry’s zombie issue. It keeps coming back year after year, but never resolved. And it’s a complex one which divides opinion. In this piece, I’m not looking to hash out the rights or wrongs of the companies involved in the latest sagas or to talk about the particulars of these cases, but to draw out some of the perspectives that mean this issue may never be fully resolved.

What are Diacetyl and Acetyl Propionyl?

DA/AP are compounds of the diketone class. DA, in particular, exists widely in nature, and is responsible for the buttery taste of many foods and beverages. It’s absolutely safe to eat or drink, but inhalation is known to be problematic. A number of cases of “Bronchiolitis Obliterans” in popcorn factory workers exposed to DA led authorities to create very strict limits to the amount of DA that workers may be exposed to. It has since been discovered in workers in other manufacturing plants. Bronchiolitis Obliterans is a condition in which irreversible scarring to the lungs is produced, in serious cases requiring lung-transplants. Ironically, the only other known causes of Bronchiolitis Obliterans is lung transplants themselves.

Acetyl Propionyl has a very similar taste profile to DA, and it appears many manufacturers may have chosen to use it in e-liquid as a replacement for Diacetyl in the mistaken belief that AP is safe or safer. There’s ample reason to assume that AP has almost exactly the same safety profile as DA.

Why are DA/AP in e-liquids?Short answer, because they taste great. In addition to being a buttery flavor, DA/AP can give fruit flavors a “ripe” characteristic and are, in a sense, the “monosodium glutamate” flavor-enhancer of vaping.
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The longer answer is a bit more interesting. In 2010, the vaping community became aware that DA was present in e-liquids and that this was a problem, and the few e-liquid manufacturers who were around back then took it seriously enough to make efforts to remove it from their e-liquids. Those manufacturers requested of their flavor suppliers that the flavoring compounds they supply did not contain DA, and most thought that this was the end of the story.

Skip forward to 2014, and Dr. Konstantinos Farsalinos was conducting some tests on e-liquids from a German supplier, and he made a discovery: the e-liquid contained DA in concentrations far higher than the NIOSH occupational hazard levels, and yet the manufacturer was absolutely unaware that there was any DA, despite having previously tested for it. So what had happened?

Quite simply, there is not a one-size fits all testing approach that is appropriate to shoehorn e-liquids into (although see this document by Nicoventures/BAT). The laboratory must know what they are looking for, and they must set the correct “limits of detection” in their equipment. Standard GC/MS wasn’t picking up DA because the limit of detection was set at around 1%, which is way above the NIOSH DA limits.

Dr Farsalinos was shocked. He assumed that if this e-liquid contained DA, and the manufacturers were unaware of this, then others would have the same issue. He went to the vaping community and crowdsourced funding for a large test of popular e-liquid brands which he purchased anonymously. Again, what came back shocked him – the vast majority (74%) of the sweet flavored liquids he tested came back with DA/AP, and 47.3% of DA and 41.5% of AP-containing samples exposed consumers to levels higher than the safety limits.. Rather than publish the names of these companies, he wrote to them directly telling them the issue and urging them to remove DA/AP from their future stocks.

Clearly, with some companies at least, this has not happened.

So, are these chemicals dangerous to vapers?

This is the $64k question. Those cases in which diacetyl was seen directly to cause broncholitis obliterans were cases in which workers were exposed to an actual vapor from heated flavorings. Despite the name, vaping itself is actually not, in the main, the inhalation of a vapor, but of an aerosol. In an aerosol, the particles from the gaseous phase have condensed into larger droplets. It’s unclear whether these droplets are capable of depositing DA/AP deep within the lung.

However, there is a vapor component to the output of e-cigarettes, and this likely varies according to the composition of e-liquid. For example, greater water content in e-liquid may result in a greater vapor component, and it’s possible a greater vapor component would lead to DA/AP being delivered deep into the lung tissue. The fact is we simply do not know at this stage what the dynamics are.
Fine, but where are all the dead vapers?

​Many vapers make the following points in defence of DA/AP: Firstly, that in over 7 years of popular usage of e-cigarettes no-one has suffered Broncholitis Obliterans, and secondly that smoked tobacco typically contains more diacetyl than those e-liquids in which it is found.

However, this line of reasoning falls down. While it is true that DA has not caused fatal Bronchiolitis Obliterans in vapers, there is great uncertainty about its contribution to disease amongst smokers. Firstly, COPD and emphysema are conditions whose causes are not fully understood; it’s likely that DA has at least some contributing factor to both (As stated by Farsalinos at GFN). Secondly, it’s likely that Bronchiolitis Obliterans is actually underdiagnosed. A positive diagnosis requires invasive biopsies, and so most smoking related respiratory conditions are diagnosed as COPD or emphysema.

Regardless, DA/AP do not need to be in e-liquid, and so their inclusion can be thought of as an “avoidable risk”. After all, you can vape e-liquid with no flavors at all.

More on this blog can be found at:
https://vaping.com/blog/comment/confused-about-diacetyl-you-should-be/

Finally, a video – Dr. Anne Hubbs discussing DA/AP inhalation, the history of popcorn lung, and DA/AP in e-cigarettes