Does vaping cause popcorn lung?
No. There’s no good evidence that e-cigarettes could cause the lung condition called popcorn lung. There’s been no cases of popcorn lung reported in people who use e-cigarettes.
What is popcorn lung?
Popcorn lung (bronchiolitis obliterans) is a type of lung disease, but it is not cancer. Although popcorn lung is very rare, some e-cigarette users may worry about it.
A link between breathing in a chemical called diacetyl was made when a cluster of popcorn factory workers were all found to have the rare lung condition. It was not related to use of e-cigarettes. And more research is needed on the apparent link between diacetyl and popcorn lung. This includes the amount of the chemical at which any damage might occur.
What does the evidence really say about diacetyl and e-cigarettes?
A few studies, published around 2015, looked at whether e-cigarette liquids available at the time contained diacetyl. They found that a large proportion of e-liquid flavours tested did contain some level of diacetyl. The idea that e-cigarettes could cause popcorn lung came from these studies.
However, this study didn’t look at whether there was a link between e-cigarette use and popcorn lung in people. So far, there’s no good evidence that e-cigarettes could cause popcorn lung.
In the UK, diacetyl was banned in e-cigarette liquid under the EU Tobacco Products Directive (TPD) in 2016. So, e-liquids sold in the UK shouldn’t contain diacetyl. Current research finds that e-cigarettes are far less harmful than smoking and there’s growing evidence they may help some people to quit.
Allen, J. G. et al. Flavoring Chemicals in E-Cigarettes: Diacetyl, 2,3-Pentanedione, and Acetoin in a Sample of 51 Products, Including Fruit-, Candy-, and Cocktail-Flavored E-Cigarettes. Environ. Health. Persp. 124, 733–739 (2016).
Centres for Disease Control and Prevention. Fixed obstructive lung disease in workers at a microwave popcorn factory--Missouri, 2000-2002. Morb. Moral. Wkly. Rep. 51, 345-347 (2002).
NHS UK. Flavourings found in e-cigarettes linked to ‘popcorn lung’ (2017). https://www.nhs.uk/news/heart-and-lungs/flavouring-found-in-e-cigarettes-linked-to-popcorn-lung/