Up in steam: ESR scientists reveal what's really in vape liquid

A groundbreaking vaping study indicates harmful bacteria, substances and chemicals are lurking in some vape products and are not being accurately reported on packaging.

Led by ESR’s Pharmaceutical Programme Team Leader Jared Doncliff and Senior Scientist Dr Robyn Somerville, the team analysed more than 150 vaping products sold in New Zealand in what is the largest local study of its kind to date.

While experts agree that vaping has a role in supporting smoking cessation and that vaping products are less harmful than smoking tobacco, they are not considered completely harmless. There is also a lot of anecdotal information emerging of people, especially teenagers, who are picking up vaping but yet who have never smoked cigarettes. It is important to provide this group with more information about the safety of vape products to enable them to make informed decisions. The team says this research fills a significant knowledge gap.

The team looked for a range of potential constituents in vape liquids including flavours, controlled substances, bacterial endotoxins, colours, ethanol (alcohol), and nicotine.

The nicotine levels of over half (58 per cent) of samples were more than 10 per cent higher or lower than the nicotine content labelled on packaging. In one sample, the nicotine content was 63 per cent higher than indicated on packaging.

Of most surprise was the presence in one sample the presence of Streptococcus salivarius and Granulicatella: bacteria generally associated with the mouth. This despite the product in question supposedly being manufactured and bottled in a ‘class 7 clean room’, at least according to its packaging.

Legislation covering vaping is in the process of being strengthened, with additional regulations having come into effect on 11 August 2021 banning most retailers from selling non-menthol, mint or tobacco flavoured vape liquid. Despite this, specialty vaping stores like those from which samples for this research were sourced, are still permitted to sell a range of flavours – making this study all the more necessary for supporting consumers to understand what’s in the products they vape.

The research team is planning future studies in this space.

Ethanol detection

Among the 106 products analysed, 95% contained ethanol:

  • 83% were equal to/less than 1% ethanol v/v (volume for volume)
  • 8% were between 1 and 2% ethanol v/v
  • 6% were between 2 and 3% ethanol v/v
  • 3% were 3% or more ehtanol v/v
  • No ingredient or warning labels noted the presence of ethanol.

Nicotine label claims

Of 92 products analysed for nicotine:

  • 51% had more than 10% lower nictoine content than the label claimed (between 11 - 67% lower)
  • 42% of samples had within ± 10% of the labelled nicotine content
  • 7% had more than 10% above label claim (between 12 - 63% higher)

One product with a label claim of zero nicotine contained 0.46 mg/mL nicotine.