Chemicals used to produce vapes could be acutely toxic when heated and inhaled, according to research.
Vaping devices heat the liquid flavouring to high temperatures to form an aerosol that is then inhaled. They contain chemicals including vegetable glycerin, propylene glycol, nicotine and flavourings, blended in various amounts.
Previous experiments have shown that some fruit-flavoured vapes – such as strawberry, melon and blueberry – produce dangerous compounds called volatile carbonyls due to this heating process.
These compounds are known to have health implications for chronic obstructive pulmonary disease (COPD), cardiovascular disease and cancers.
With so many chemicals used in tens of thousands of different vape products, conducting experiments to test every brand and flavour for toxicity could take decades of research.
Instead, the study used AI to analyse the chemical composition of 180 vape flavours and simulate how they decompose when heated. The research, published in Scientific Reports, predicted that vapes produce 127 “acutely toxic” chemicals, 153 “health hazards” and 225 “irritants”.
Nearly every flavour put through the AI predictor showed at least one product that was classified as a health hazard, with many predicting several. The toxins were associated with vapes containing no nicotine, as well as those with.
The research team at RCSI University of Medicine and Health Sciences, Dublin, conclude there is a “potential public health threat facing the 4.5 million vapers in the UK” and an urgent need for “enhanced restrictions” on flavours and regulations that are reflective of the health risks of vaping, especially for young people.
In January, the government announced that it would ban disposable vapes and restrict sweet and fruity flavours. Lead author Donal O’Shea, professor of chemistry at RCSI, said that the UK government should go further and remove all flavours from vapes.
It is crucial to understand the impact of flavoured vapes on health “before it’s too late”, he added.
“It is plausible that we are on the cusp of a new wave of chronic diseases that will emerge 15 to 20 years from now due to these exposures.”
Given the popularity of flavoured vapes among non-smoking teenagers and young adults, understanding the long-term effects of these products on public health, morbidity and mortality is crucial, the study concludes.
“Without comprehensive regulation, as we try to treat the nicotine addictions of older tobacco smokers, there is a substantial risk of transferring new health issues to younger generations.”
Responding to the findings, a Department of Health and Social Care spokesperson said: “The health advice is clear – if you don’t smoke, don’t vape and children should never vape.
“That’s why we are banning disposable vapes and our tobacco and vapes bill includes powers to limit flavours, packaging and displays of vapes to reduce the appeal to children.
“It is clear that flavours like cotton candy and cherry cola are deliberately being targeted at children, not adult smokers trying to quit, which is completely unacceptable. That is why we are taking decisive action and will be restricting vape flavours.”
Prof Sanjay Agrawal, the Royal College of Physicians’ special adviser on tobacco, said that while vaping can be a very effective way to break the addiction to tobacco, it should only be used for this purpose.
“Vaping is not risk-free, so those who don’t smoke, including children and young people, should not vape either,” he said.
John Dunne, director general at the trade body the UK Vaping Industry Association, said: “The science on vaping is very clear, it is the most effective way for smokers to quit and is at least 95% less harmful than smoking. Every chemical used in vaping e-liquid in the UK is stringently tested, including analysing chemicals when heated, and is only approved for use by the UK government if it is deemed safe.”
