Self-proclaimed experts who offer up claims of the risk from bronchiolitis obliterans (the official name for popcorn lung) are like Doctor Michelle Peace. Peace appeared on New Zealand television to give her opinion on the subject.
Despite holding a BA in Chemistry and Biology, an MSc in Forensic Toxicology and a PhD in Forensic Toxicology, the best she could muster was: “I am familiar with popcorn lung. So when you think about popcorn lung. Umm. What generates it is, err, you’re inhaling chemicals that’s going to cause some kind of damage to the interior of the lung tissue. Err, and when you damage the interior of the lung tissue, your ability to, err, you know, inhale and process oxygen is going to be compromised.”
Such eloquence leads The Sun journalist to believe vaping juices containing diacetyl, “causes inflammation, scarring and constriction of the bronchioles”.
There are a number of problems with this misinformation.
In 2014, Dr Konstantinos Farsalinos did discover the presence of diacetyl in eliquids – but the study prompted a wholesale change in the juice manufacturing industry. Canada removed stocks from shelves and vendors began to test their liquids. The consumer-led demand led to flavour houses releasing diacetyl-free flavourings.
Despite this, Farsalinos pointed out that the risk was small in smokers: “Popcorn lung is very rare even in those exposed to high levels. 1 in 1000 chance of developing an chronic obstructed lung disease, 15% of smokers develop this, so it is likely diketones are operating in conjunction with other chemicals.”
He concluded that the risk posed to vapers was negligible in comparison.
Public Health England’s Tobacco Control Programme Lead Martin Dockrell pointed out a couple of month’s ago that such talk of popcorn lung risk contributed to the “inaccuracies and misconceptions about e-cigarettes and vaping”.
Most claims of risk date back to a debunked study https://ehp.niehs.nih.gov/wp-content/uploads/advpub/2015/12/ehp.1510185.acco.pdf - that has since been removed from the website. Farsalinos said: “the authors failed to mention the presence of these compounds in tobacco cigarette smoke. This omission creates the impression that e-cigarettes are exposing users to a new chemical hazard, while in reality their exposure will be much lower compared to smoking.”
Dockrell went on to highlight: “Diacetyl is banned as an ingredient from e-cigarettes and e-liquids in the UK. It had been detected in some e-liquid flavourings in the past, but at levels hundreds of times lower than in cigarette smoke. Even at these levels, smoking is not a major risk factor for this rare disease.”
The dose makes the poison, but the poison isn’t even present in eliquid these days.
The Public Health England report Evidence review of e-cigarettes and heated tobacco products 2018 reaffirms Dockrell’s point: “One of the most commonly heard safety concerns about flavourings used in e-liquids is that flavours that contain diacetyl might cause bronchiolitis obliterans (also referred to as 'popcorn lung)', a serious disease that has been linked to the exposure to high levels of this chemical in popcorn plant workers. Diacetyl has been detected in some EC flavourings, but at hundreds of times lower levels than observed in cigarette smoke. Given that even at these levels, smoking is not a major risk factor for this rare disease, the diacetyl content in EC flavourings is unlikely to pose much risk.”
Vaping isn’t safe, it’s safer than smoking (estimated at 95% by PHE), but there is no risk of contracting bronchiolitis obliterans (popcorn lung) from vaping diacetyl-free eliquids.