The Facts About Diacetyl: What Vapers Need to Know

The Facts About Diacetyl: What Vapers Need to Know

A real worry or unwarranted concern.

14 August 2023 | Hannah Rubery

The Facts About Diacetyl: What Vapers Need to Know (Image)

In the landscape of modern health debates, few topics have generated as much heat and controversy as vaping. The emergence of electronic cigarettes and vape devices, touted as a safer alternative to traditional cigarettes, has spurred numerous discussions and investigations. Even after the buzz surrounding some topics has died down, the questions still linger in the air.

One such ingredient that has sparked significant concern and media uproar is diacetyl, a chemical compound potentially linked to a condition known as 'popcorn lung'. Despite its small presence in E-Liquids, the implications of diacetyl in vaping has led to widespread scrutiny, heated debates, and regulatory changes in countries like the UK.

What is diacetyl?

Diacetyl, scientifically known as 2,3-butanedione, is an organic compound that is yellow or green in colour and has a distinctly buttery flavour. As a result of its appealing taste, it's widely used in the food industry as a flavouring agent, particularly in dairy products, candies, and baked goods. In addition to being synthetically produced, diacetyl is a natural by-product of fermentation processes such as brewing beer and making cultured butter.

The compound is generally deemed safe for ingestion; however, its inhalation in large amounts has raised concerns in certain occupational environments. The potential risk associated with diacetyl in vaping, despite being present in far smaller amounts than in cigarettes, has prompted an ongoing debate about its safety. A little something you've undoubtedly heard before called 'popcorn lung'.

What caused the 'popcorn lung' panic?

'Popcorn lung', or bronchiolitis obliterans, is a severe and irreversible lung disease characterized by the narrowing of the bronchioles, the tiny airways in your lungs. This condition earned its colloquial name following a significant incident in the early 2000s at a microwave popcorn manufacturing facility.

Workers in the factory were exposed to very high levels of diacetyl used to give the product its buttery flavour. This prolonged exposure led to several employees developing serious lung conditions, thus triggering the association between diacetyl and 'popcorn lung'. The occurrence of this incident has drawn attention to the risks of inhaling diacetyl, including in contexts such as vaping where the compound is present in much smaller concentrations.

Is diacetyl dangerous?

The level of diacetyl found in vape liquids is significantly lower in comparison to traditional cigarettes and far less than the high concentration that caused the 'popcorn lung' incident in the popcorn factory. Research suggests that, on average, the diacetyl content in e-liquids is hundreds of times lower than that in cigarettes. Yet, the 'popcorn lung' incident involved workers inhaling diacetyl in concentrations far exceeding the levels found in either vapes or cigarettes.

Despite the lower concentration in vape liquids, it is important to note that any level of inhalation may still present potential risks, leading to ongoing concern and debate about the safety of diacetyl in vaping.

Diacetyl Banned in the UK

In the wake of these debates and with the intention to safeguard public health, the United Kingdom chose to err on the side of caution and instituted a ban on the use of diacetyl in vaping products. Even though the concentrations of diacetyl found in E-Liquids were significantly lower than those present in traditional cigarettes, and far less than the levels that led to 'popcorn lung' in the popcorn factory workers, the UK regulatory authorities decided that any potential risk was too much.

As a result, any E-Liquids that are legally sold in the UK today do not contain diacetyl, ensuring that vapers can enjoy their experience without the fear of inhaling this controversial compound. Though this does mean that vapers should be cautious when buying potentially illegal/illicit vapes - check out our previous article on spotting fake vapes for more information.


In conclusion, the worry surrounding diacetyl in vaping is not entirely unfounded given its potential association with 'popcorn lung' from occupational exposure. However, it's critical to note that the diacetyl content in vape liquids is significantly lower than what's found in traditional cigarettes and is minuscule compared to the levels that caused 'popcorn lung' in popcorn factory workers.

Crucially, for vapers in the UK, there's the reassurance of stringent regulations. The UK has taken a proactive stance and banned the use of diacetyl in vaping products altogether, as one of the many measures to protect public health. This means any E-Liquid that is legally sold in the UK does not contain this compound.

So, as long as UK vapers are using legal vaping products, they can confidently enjoy their experience without the worry of diacetyl exposure. This highlights the importance of buying only legal vaping products from reputable sources, ensuring not only a safer vaping experience but also peace of mind.