They are flavoured, colourful and popular with teenagers, but new Australian research is discovering mounting evidence that vapes are also unsafe to use.
Curtin University respiratory physiologist Alexander Larcombe studied 65 common liquids used in vapes from local suppliers that are available in Australia.
Dr Larcombe said the results showed that many vapes contained carcinogenic and other harmful ingredients.
The study is the extension of a 2019 study published by the same researchers that looked at 10 vape ingredients. It is the most comprehensive study of products available in Australia to date.
It is estimated that more than 200,000 Australians use vapes, however, those using them with nicotine must have a prescription from a doctor.
Until recently, nicotine-free flavours were far more easily available online and from tobacconists.
The Therapeutic Goods Administration has recently cracked down on imports but can only regulate those with nicotine and imports of officially banned flavours, and there are far fewer regulations around the manufacture and supply of flavours alone within Australia.
In the latest study, the researchers looked at the “nicotine-free” products when they were fresh and after they had been repeatedly heated and cooled in a vape.
Dr Larcombe said his research, published in the Medical Journal of Australia on Monday, should counter common beliefs among vapers.
“A lot of the people who are using these things aren’t trying to quit, they’re teenagers who are trying them out at school.”
‘A dirty manufacturing process’
Researchers found evidence of a group of chemicals called polycyclic aromatic hydrocarbons (PAHs), which has been linked to lung, bladder and gastrointestinal cancers.
Dr Larcombe said the researchers found PAHs at a range of levels.
“There’s not really any safe level of exposure to PAH that’s accepted,” he said.
The researchers also found “dangerously high levels” of lung irritant benzaldehyde, which is added to vapes to give them an almond flavour, in 61 of the 65 samples.
“It changes how some of the cells in your lungs work,” Dr Larcombe said. “It impairs your lungs that are normally responsible for cleaning up pathogens.”
The study also found high levels of a cinnamon flavouring known as trans-cinnamaldehyde in up to 48 of the liquids.
Its potential health effects are so concerning the substance has been added by the TGA to an Australian list of banned flavours.
Six of the flavoured vapes promoted as nicotine-free still had traces of nicotine.
Dr Larcombe said that was against Australian law.
“It’s indicative of a dirty manufacturing process or Australian companies getting [the liquids] from overseas,” he said.
Pesticides, hospital cleaning agents found
Researchers also detected a chemical called 2-chlorophenol in up to 30 samples, which is commonly used in disinfectants and pesticides.
Dr Larcombe said the researchers suspected it was residue from pesticides sprayed on the crops used to generate glycerol, one of the main ingredients in the liquids.
“It was surprising and concerning that such a harmful chemical could be in there and people are breathing it in.”
One of the main flavour enhancers in many vapes is benzyl alcohol. It was found in 42 of the liquids and, in some cases, at very high levels.
“What it does to the respiratory tract or what it does to your lungs from heating and breathing [it in] is unknown at this stage,” Dr Larcombe said.
This was also a trace of a vanilla flavour called ethyl vanillin, which was in up to 59 of the liquids at reasonably high levels.
Vapes also have a metal heating coil that heats the liquid, which degrades over time with use.
Dr Larcombe said it was made up of chromium, nickel and iron and that researchers had found “low levels” of those heavy metals.
He said the plastic container that held the liquid also broke down over time.
“You’re probably breathing in microplastics and other stuff as well,” he said.
Dr Larcombe said most Australians would not know there was a difference between eating a flavour and inhaling it.
That was because when a chemical was heated — like what happened in the vaping process — it changed its chemical structure.
“Lower temperature heating can be just as bad, if not worse, in generating nasty output,” he said.
Calls for stricter manufacturing rules
The findings have prompted Andrew Forrest’s Minderoo Foundation to call for sweeping reforms to production of the liquids in Australia.
Minderoo Foundation — a Perth-based philanthropic organisation — said it funded the research in the area as part of its Collaborate Against Cancer initiative.
“We now have the evidence to support consistent tobacco licensing in all states,” Minderoo Foundation Collaborate Against Cancer initiative chief executive Steve Burnell said.
“[As well as] restrictions on non-nicotine vaping products, changes to the Tobacco Advertising Prohibition Act and much stricter monitoring and compliance — all are required to protect our young people from these toxic products.”
University of Adelaide research scientist Dr Miranda Ween — who is considered a world leader in e-cigarette research — backed the findings.
She said it highlighted the need to regulate flavoured vapes, not just those that contained nicotine.
“These people don’t necessarily need to have good manufacturing practice qualifications.”
Dr Ween said some of the advice and information about vapes from suppliers was not accurate nor based on the latest research.
In a statement, a spokesperson for the regulator, the TGA, said it would be reviewing its standards for nicotine-based vapes next year, but did not indicate if it would include those that just contained flavours.
The spokesperson said it tested products intercepted at the border for nicotine and banned ingredients.
“This testing is part of a broader compliance program to monitor and address unlawful importation, advertising and supply.”