What Is Popcorn Lung
Popcorn lung is the informal name for a rare lung condition known as bronchiolitis obliterans. It causes scarring and inflammation in the small airways of the lungs, leading to symptoms such as coughing, wheezing and shortness of breath. The term originated in the early 2000s after workers at a popcorn factory developed the condition due to long-term exposure to diacetyl, a chemical used to create buttery flavouring in microwave popcorn. Since then, the name has become commonly associated with concerns about chemical inhalation, including from e-cigarette vapour.

Where the Concern About Vaping Began
The connection between vaping and popcorn lung comes from reports that some e-liquids, especially those with sweet or buttery flavours, once contained diacetyl. When inhaled over time in large quantities, diacetyl has been linked to lung damage. This raised understandable concerns about whether vaping products could pose a similar risk. While early studies found traces of diacetyl in some flavoured e-liquids, the levels were generally far lower than those found in tobacco smoke, which also contains the chemical. However, the issue sparked further investigation into the ingredients used in e-cigarettes and how they are regulated in the UK.

Current UK Regulations on Diacetyl in Vapes
In the UK, vaping products are regulated under the Tobacco and Related Products Regulations (TRPR), which are based on the European Union's Tobacco Products Directive. These rules require e-liquids to be tested and approved before being sold. One key requirement is that e-liquids must not contain ingredients that pose a risk to human health in heated or inhaled form. Diacetyl is not permitted in legally sold e-liquids in the UK. As a result, any reputable brand or retailer should not be offering products containing this chemical. This significantly reduces the risk of developing popcorn lung from vaping regulated e-liquids in the UK.

How Common Is Popcorn Lung and Is It Linked to Vaping
Popcorn lung remains a very rare condition, and to date, there have been no confirmed cases of it being caused by e-cigarette use in the UK. While the concern was based on a real chemical hazard, the levels of exposure needed to cause bronchiolitis obliterans were much higher than those found in e-liquids, even in unregulated markets. In contrast, cigarette smoke contains far more diacetyl than early e-liquids ever did, yet smoking has not been strongly associated with popcorn lung. This suggests that while the risk cannot be entirely dismissed in theory, it is extremely low in practice when using legal vape products.

The Role of Responsible Vaping and Product Choice
Choosing regulated products from trusted UK retailers is essential for ensuring safety. E-liquids sold under TRPR regulations must meet strict manufacturing and labelling standards, and ingredients like diacetyl are banned. Unregulated or imported products bought online or from informal sources may not follow these safety rules and could contain prohibited chemicals. It is always wise to check that a product is registered with the Medicines and Healthcare products Regulatory Agency (MHRA) and comes from a recognised brand. Using a regulated vape product significantly reduces the risk of inhaling anything harmful.

Separating Myths from Evidence
Despite public concern and sensational headlines, there is currently no evidence that vaping causes popcorn lung when using regulated UK products. The myth has persisted due to early concerns about flavourings and the name itself, which sounds dramatic and alarming. This has led to some confusion, especially among new or potential vapers trying to weigh up the risks. In truth, vaping does not involve the same exposure to diacetyl that led to popcorn lung cases in factories. For people using e-cigarettes to quit smoking, the benefits of switching to vaping far outweigh the very low theoretical risk of this condition.

Final Thought on Vaping and Popcorn Lung
Vaping does not cause popcorn lung when using properly regulated products available in the UK. While the condition is real and serious, it was linked to high levels of exposure to a specific chemical that is now banned in UK e-liquids. The idea that vaping causes popcorn lung has become a persistent myth, but there are no documented cases to support it. As always, choosing legal, tested vape products and avoiding unregulated e-liquids is the best way to stay safe. For those switching from smoking, vaping remains a far less harmful alternative and is not associated with this rare lung condition.