An expert has warned against vaping as it could cause an irreversible condition known as "popcorn lung".
Vaping might look like safer alternative to smoking, but according to a leading health expert, it can leave you with a condition so severe it’s been dubbed “popcorn lung” — and once it hits, there’s no coming back.
Professor Donal O'Shea, a chemistry expert from RCSI University of Medicine and Health Sciences, has sounded the alarm on the dangers of flavoured vapes, especially after a 17-year-old was recently diagnosed with bronchiolitis obliterans — the irreversible condition behind the nickname.
In an eye-opening article for The Conversation, O’Shea explains why prevention is the only real option when it comes to avoiding this debilitating illness — and it all comes down to what you’re inhaling.
Why “Popcorn Lung” Isn’t Just a Scary Name
The name “popcorn lung” isn’t some TikTok exaggeration.
As Professor O'Shea explains, the term dates back to when workers at a microwave popcorn factory started developing lung issues from inhaling a chemical called diacetyl.
“Similarly to the popcorn factory, flavoured vapes contain the chemical diacetyl – which, when aerosolised, becomes a 'toxic inhalant',” he says.
And it doesn’t take much to do serious damage.
“It causes inflammation and scarring in the bronchioles (the smallest branches of the lungs), making it increasingly difficult for air to move through,” O’Shea warns.
“There’s no cure for popcorn lung. Once the lungs are damaged, treatment is limited to managing symptoms. This can include bronchodilators, steroids, and in extreme cases, lung transplantation. For this reason, prevention – not treatment – is the best and only defence.”
Why Your Favourite Vape Flavour Might Be More Dangerous Than You Think
It’s not just about the diacetyl either. Vaping, especially with flavoured products, involves inhaling a chemical cocktail — many of which haven’t been properly studied for long-term inhalation safety.
“Including volatile carbonyls like formaldehyde and acetaldehyde – both of which have also been detected in e-cigarette vapours,” O'Shea adds.
And the scale of chemical exposure is massive.
“Experts have estimated there being 'over 180 different flavouring agents used in e-cigarette products today' which, 'when heated' break down into 'new compounds' that haven't all been 'tested for inhalation safety',” he explains.
So even if diacetyl isn’t the only threat, it’s far from the only one.
“Because vapers’ lungs are exposed to so many chemicals, it’s not possible to directly prove that diacetyl is the cause of the disease in any specific case. But that doesn’t negate the proven risks of inhaling it,” he continues.
“Even if diacetyl isn’t the sole culprit, cumulative exposure to multiple chemicals and their byproducts could increase the risk of popcorn lung and other respiratory conditions.”
Banned in Some Places — But Not Everywhere
While diacetyl is banned in vapes across the EU and UK, it still shows up in illegal products — and it’s completely legal in many other countries, including the US.
That means even if you think you're vaping “safely,” the chemicals you’re inhaling could still be causing irreversible harm to your lungs.
And once you’ve got it, it’s for life.