From October 1, it is prohibited to buy e-liquids containing nicotine without a doctor’s prescription anywhere in Australia except South Australia.
But vaping with nicotine-free e-liquids is not illegal in Australia (although e-cigarettes themselves are illegal in some jurisdictions).
Vaping is becoming more and more popular in Australia, especially among young people.
I was one of the leaders of a research group looking to find out what is in the nicotine-free e-liquids that vapers inhale and their potential health effects.
Our research, published this week in The Medical Journal of Australia, found that most e-liquids contain chemicals known to cause breathing problems and lung damage when inhaled. Most of them contained ingredients that have since been banned by the Australian drug regulator, Therapeutic Goods Administration (TGA).
We also found that all e-liquids contain substances with no known health effects if inhaled.
It is understood that vaping is unsafe and e-cigarettes have not been approved as a smoking cessation device.
Read more: Vaping: As an imaging specialist, I fear lethal effects on the lungs of people.
What did we study?
A few years ago, we did a small study that included chemical analysis of ten e-liquids purchased in Australia. All of them were marked as “nicotine-free”.
Our study, published in The Medical Journal of Australia in 2019, was unexpected and unsettling. We found that 60% of liquids contain nicotine. In some cases, it was at a high enough level not to be considered a trace pollution.
We also found that all ten e-liquids contain a chemical called 2-chlorophenol, which is often used in pesticides and disinfectants and is a known skin and lung irritant.
Most e-liquids also contain “2-amino-octanoic acid,” which is an amino acid found in mammalian biological products, including feces, urine, and blood. Its presence was potentially the result of contamination by one of these substances during manufacturing or packaging processes.
Our results prompted us to expand on our previous research.
This time, we analyzed 65 Australian e-liquids, including a method aimed at better understanding how heating e-liquids can change their chemical constituents.
This was the most extensive analysis of Australian e-liquids to date by Curtin University and the Valliana Respiratory Research Center in conjunction with the Lung Foundation Australia, Minderoo Foundation and Cancer Council Western Australia.
All of the e-liquids we studied were purchased online or from brick-and-mortar stores across Australia. They were all advertised as “bestsellers”, Australian and nicotine free, so it is likely that they represent something that many Australian vapers might use.
None of the e-liquids came with a detailed ingredient list, so users cannot know what chemicals they are inhaling. This also means that all e-liquids we tested will not comply with European Union labeling regulations.
Read More: Vaping is fascinated on social media, endangering youth
What else have we found?
Many of the flavors we find are “generally considered safe” by the FDA for use in foods and beverages. But there is a big difference between a chemical that is safe to swallow and one that is safe to inhale for a long time.
We also found nicotine in some e-liquids, but it was found much less frequently and in much lower concentrations than in our previous study. This may indicate a cleaner manufacturing process.
We tested only the “free base” nicotine, which is commonly used in both conventional cigarettes and nicotine replacement therapy. Thus, e-liquids may have contained a different type of nicotine called nicotine salts, which are much more commonly used today than they were a few years ago.
We also rediscovered 2-chlorophenol, although it was only found in half of the e-liquids we tested. However, contamination of e-liquids with this known toxic chemical with no compelling reason to be present remains a major concern.
A number of other chemicals of concern have commonly been found, including benzaldehyde, trans-cinnamaldehyde and menthol. These chemicals are added to give them almond, cinnamon and mint flavors, respectively.
Benzaldehyde has been found in all but four e-liquids, while menthol and trans-cinnamaldehyde have been found in about three-quarters of e-liquids. The presence of these chemical flavors has been a concern for a number of reasons.
First, they are all known to alter the effect of nicotine. Menthol is addictive to nicotine.
Benzaldehyde and trans-cinnamaldehyde are known to inhibit an enzyme called “CYP2A6”. CYP2A6 is responsible for the metabolism and detoxification of many drugs that humans are exposed to, including nicotine.
When these flavoring chemicals interfere with its function, it means that a vaper using e-liquids containing nicotine will have nicotine in the body for a longer period of time before it is processed by the body.
Benzaldehyde is also an irritant to the respiratory tract and can reduce a person’s ability to fight lung infections. Trans-cinnamaldehyde has an even more severe effect on the immune cells of the lungs.
Both of these chemicals are now on the TGA e-liquid ingredient list, which means they are banned in Australian e-liquids. Menthol is not banned by the TGA, but in some countries it is banned in tobacco cigarettes. In this study, e-liquids were analyzed before the ban came into effect.
This study clearly shows that Australian e-cigarette liquids contain a number of chemicals known to adversely affect health, or for which potential health effects from inhalation exposure are unknown.
Much more research is needed in this area before we can make informed decisions about using e-cigarettes without nicotine and nicotine, and better understand how vaping affects our health.
The author would like to thank Prof. Ben Mullins and Dr. Sebastian Allard of Curtin University who co-led this research project.