Popcorn lung - what is it and why should you care?

A very common question/comment on Vejpkollen's social media is the one about vejpning and popcorn lung. Popcorn lung is another name for the lung disease bronchiolitis obliterans.
The disease causes scarring of the lungs and can be linked, among other things, to inhalation of the chemical diacetyl. The disease leads to chronic breathing difficulties, similar in many respects to COPD.
But what does this have to do with e-cigarettes and why has the myth that vejp users are at risk of popcorn lung stuck in the debate?

– This is an article created to explain and broaden the discussion about a claim that often appears on Vejkollen's social media. Do you have more questions? Don't hesitate to ask them to the editors! –

Popcorn lung. The image of a lung filled with popcorn is both comical and scary. It is an image that is widely used on social media - not least to attract attention and spread a negative message about the 'risks' of e-cigarettes and vejpning. Children and young people are often used to drive the stories. Sometimes even the mainstream media pick up on these stories, with young people 'testifying' about how their lungs are now 'ruined forever' because they have vejpat. It's a very effective way of getting a message across, isn't it?

But the doctor said that...

Unfortunately, or rather fortunately, the 'information' disseminated in these posts is directly, or largely, misleading. Popcorn lung (or the disease bronchiolitis obliterans) has to date never actually been linked to any cases where the cause is vejpning (with nicotine), not in any scientifically reviewed case studies, not in any overall summaries. And the likelihood of this ever happening is almost non-existent (read more about this below). In other words, the substance of the stories is fairly easy to check - 9 times out of 10, it's a young person who has had a problem with their lungs, gone to their doctor who has told them that vejpa is dangerous and told them they need to stop.

The fact is that it takes quite extensive research to establish bronchiolitis obliterans. It requires a so-called bronchoscopy, a tissue sample from the lung with all that this entails.

The cause of the supposed lung damage is therefore likely to be left to speculation, and is often confused with outright views that vejpning should be regulated in one way or another and that use among young people needs to be reduced.

All in all, this means that the MYTH of popcorn lung persists. It's simply too "good an image" NOT to highlight in the context of the campaigns run to discourage the use of e-cigarettes. And unfortunately, this has led to gross misconceptions about the relevant health risks associated with vejpning, particularly among smokers.

But what is it all about?

First and foremost. What is bronchiolitis obliterans (aka. popcorn lung)?
This is how the disease is generally described (according to Wikipedia):

"Bronchiolitis obliterans is an uncommon disease in the general population. However, it affects about 75 per cent of people within 10 years of a lung transplant and up to 10 % of those who have received a bone marrow transplant from another person. The disease was first clearly described in 1981, but there are reports of similar cases dating back to 1956. The term itself bronchiolitis obliterans was first used by the doctor Reynaud in 1835.

Symptom:

The condition leads to a gradual deterioration in breathing, wheezing and a dry cough. Symptoms may develop slowly, but in some cases they can be sudden and severe. This disease affects the lungs in a way that makes it difficult to breathe and cannot be relieved by standard bronchodilator medicines. This can be due to a number of factors, including

• Autoimmune diseases (where the body's immune system attacks its own lungs)
• Injuries from inhalation of harmful substances
• Immune response after a transplant
• Consequences of an infection
• Reaction to certain medicines

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What does this mean for vejpare?

As I said, no vejpare has to date diagnosed with "bronchiolitis obliterans" linked to the use of e-cigarettes and nicotine. In the case studies (they are quite few), it turns out that the causes are always something else, perhaps a previously undeveloped lung disease, genetic diseases, the use of e-liquid containing THC (cannabis) or simply smoking.

But of course, vejpa means that you are breathing in chemicals in greater quantities than if you were just breathing clean air. And although cigarette smoke also contains chemicals (nearly 7000) and vejpa vapour contains far fewer (nearly 100), this fact has led many people to assume that vejpa can be almost as harmful as smoking. Many even think "worse", considering that the smoke from tobacco is "natural" and the vapour from e-liquid is "unnatural". Even though it not true at all, popcorn lung "fits" very well into this puzzle, or rather the skewed perception of reality, fuelling concerns about a relatively "new" way of using nicotine.

Popcorn lung and diacetyl

But no smoke without fire, right? Bronchiolitis obliterans was found in 2000 in a number of cases where workers in a microwave popcorn factory inhaled large amounts of the substance over a long period of time diacetyl, a chemical with a butter-like flavour that was used in its production. This was the first time diacetyl was linked to bronchiolitis obliterans. It was also here that the name "popcorn lung" was coined.

Almost ten years later drew the attention of a group of vejpare that even some e-liquids contained small amounts of diacetyl. An advocacy campaign was then launched via various forums. The aim was to get e-juice manufacturers, which were not very numerous at the time, to stop using diacetyl to make certain e-juices (these are juices with creamy flavours - milkshakes, pastries, custards). Not surprisingly, this media attention. And in order to keep their customers, the major flavour manufacturers (The Flavour Apprentice, Flavour Art, Capella and others) chose to replace the diacetyl in their essences with other equivalent substances.

More diacetyl in cigarette smoke

In this context, however, it is noteworthy that even cigarette smoke contains the substance diacetyl - but in much higher concentrations than have been measured in 1TP8 vapour. Ever. Despite this, to date, no cases of bronchiolitis obliterans documented among smokers, despite decades of studies of various lung diseases affecting smokers. This is of course also true for vejpare - no cases have been documented - even though the technology has been around for more than 20 years.

Lipids in cannabis juice?

In the cases that are often referred to, and they are very few, the development of something similar to bronchiolitis obliterans rather linked to the use of e-liquid containing cannabisor the case studies have not declared what the persons in question actually has vejpat. Cannabis juice is basically a lipid product, which means that it is basically not water soluble (unlike regular e-liquid). This in turn can lead manufacturers to use various chemicals to make the juice vejpable (a non-water-soluble juice easily burns the heating element or, in the worst case, causes chemical pneumonias).

One of these substances is e-acetate (vitamin E oil). It is likely that these additives in cannabis juice have affected the lungs of many users in a way that produces symptoms similar to bronchiolitis obliterans. However, the use of a vejp to cultivate cannabis is very common in countries like the US, where THC has become a legal drug in many states.

Why this confusion?

Misunderstandings about what vejpning is and the risks associated with vejpning are quite widespread. Information is often characterised by the intensive campaign work which aims to prevention, that is, to reduce the use of nicotine products among young people. Scientists who speak out in the media are often involved in such campaigns, and similarly their research presented in a way that favours that purpose. Popcorn lung is just one example of various myths which ultimately leads to contradictory reasoning among users, doctors, researchers and opinion leaders on the issue.

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What does science actually say?

To avoid some hassle and risk editorial cherry-picking, we ran the question through our AI friend: ChatGPT.

ChatGPT is, like any other AI-based search engine, not an oracle or an "unproblematic source". The results therefore need to be read with a critical eye. But an advanced AI search can be quite instructive, especially to shed light on different aspects on contentious and infected scientific issues. What follows is a somewhat unconventional, but nonetheless interesting, summary of what the scientific community actually says about popcorn lung. The analysis also addresses why the disease is so misunderstood, in particular as regards the link to vejpning.

We put the question to ChatGPT like this:

Why does the myth of vapers getting popcorn lung persist?

In translation: Why is the myth that vejpare gets popcorn lung so persistent?

So here was the answer (we deliberately leave the word to vejpa as "vaping" because that's how ChatGPT wants it ;-):

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The myth that vaping causes popcorn lung (bronchiolitis obliterans) persists for several reasons:

1. Historical link to diacetyl
   Popcorn lung was first identified in workers in a microwave popcorn factory who inhaled large amounts of diacetyl, a chemical with a butter-like flavour. Some early e-liquids (especially those with buttery flavours) contained diacetyl, raising concerns that vaping could cause similar lung damage.
   
2. Media sensationalism
   When the link between diacetyl and lung disease became known, media outlets published scare headlines linking vaping to popcorn lung - despite studies showing that diacetyl levels in vape products were much lower than in cigarettes (which also contain diacetyl but do not cause popcorn lung).
   
3. Anti-vaping campaigns
   Some public health organisations and anti-vaping groups have exaggerated or misrepresented the risk, sometimes by confusing EVALI (a separate vaping-related lung disease linked to black market THC cartridges) with popcorn lung. This has helped perpetuate the myth.
   
4. Lack of clear explanations
   Although many experts have debunked the myth, disinformation spreads faster than corrections. The idea that vaping causes a serious lung disease is simple and scary, making it easy to believe and spread.
   
5. Debt by association
   As vaping has been linked to certain respiratory problems (e.g. irritation and inflammation), many assume that popcorn lung must be one of them, although no confirmed cases have been linked to vaping.
   

Reality check (Reality Check)
No studies have found a single case of popcorn lung caused by vaping. In addition, most reputable vape brands have removed diacetyl from their products. If cigarettes, which contain significantly more diacetyl, do not cause popcorn lung, then vejpning is unlikely to do so.

Vejpkollen asks:
What scientific sources did you use to come to this conclusion?

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A scientific review of the link between vaping and popcorn lung (bronchiolitis obliterans):

Diacetyl and Popcorn Lung

• Occupational exposure: The link between diacetyl and bronchiolitis obliterans was first identified in workers in factories producing butter-flavoured popcorn. Inhalation of large amounts of diacetyl led to severe lung damage.
• Presence in e-cigarettes: A Harvard study found that 39 out of 51 e-cigarette brands examined contained diacetyl. However, it is important to note that the levels of diacetyl in e-cigarettes are generally much lower than in traditional cigarettes.

Regulations and Measures

• Prohibitions and restrictions: Due to health risks, regions such as the UK have banned diacetyl in e-cigarettes and e-liquids under the EU Tobacco Products Directive since 2016. As a result, legal e-liquids in these areas cannot contain diacetyl.

Current Scientific Evidence

• No confirmed cases: So far, there have been no confirmed cases of popcorn lung directly linked to e-cigarette use.
• Comparative risk: As traditional cigarettes contain higher levels of diacetyl and have not been linked to popcorn lung, the risk from vaping-especially with products that follow safety regulations-appears to be low.

Conclusion

Although the presence of diacetyl in some e-liquids initially raised concerns about a possible link to popcorn lung, current scientific evidence does not support this hypothesis. Regulatory measures have further reduced the risk by restricting or banning diacetyl in e-cigarette products.

So far ChatGPT.

Vejpkollen's comment

Our AI search engine used a total of 9 sources to build their argument. Many of them are direct scientific publications. But there are also more opinion-forming hits - particularly from various university websites. This is interesting - as it often deals with the aspect of myth-making that the AI engine addresses. That "public health organisations and anti-vaping groups" uses misunderstanding and ignorance to build a kind of narrative around "risks of vejpning".

It is when the AI engine compares these texts to purely scientific sources (studies) and picks out what is considered proven (shall we call it evidence?) that it becomes more and more clear that this procedure leads to the perpetuation of the popcorn lung myth - despite the fact that there is no evidence to support it.
Below are the sources referred to by ChatGPT.

Main sources:

Wikipedia: Bronchiolitis obliterans

Popcorn Lung: A Dangerous Risk of Flavoured E-Cigarettes

Cancer Research UK: Does vaping cause popcorn lung?

Other sources:

Does vaping cause lung cancer?

Popcorn lung: What is it, and who is at risk?

Can vaping damage your lungs? What we do (and don't) know

RE: Vape related "Popcorn Lung" debunked years ago

Vaping-associated lung illnesses highlight risks to all users of electronic cigarettes

What Does Vaping Do to Your Lungs?