27 April 2017
A new study found no evidence that vapour from a commercially available e-cigarette promotes the development of cancer in laboratory cells. In contrast, smoke from a reference cigarette was positive for cancer-promoting activity, even at very low concentrations.
‘These results add to growing weight of evidence that e-cigarettes are likely to be significantly safer than conventional cigarettes,’ explains Damian Breheny lead author and Adverse Outcome Pathway Manager at British American Tobacco.
Scientists at British America Tobacco used a test called the Bhas 42 assay to compare tobacco and nicotine products for the first time. The Bhas 42 cell transformation assay assesses the carcinogenic potential of chemicals by looking for changes in a line of cells that are characteristic of tumour development.
Bhas 42 was used to compare the tumour promoter activity of vapour from Vype ePen, a commercially available e-cigarette, and smoke from a reference cigarette (3R4F), by exposing cells to the total particulate matter collected from the vapour or smoke. Results show that cigarette smoke is positive for cancer-promoting activity at concentrations as low as 6μg/mL, whereas the test e-cigarette vapour was not observed to have any in vitro cancer promoter activity at concentrations up to 120μg/mL.
The results are published today in the journal Environmental & Molecular Mutagenesis .
The Bhas 42 assay is part of a suite of in vitro tests being developed by British American Tobacco to compare the relative biological effects of e-cigarettes and tobacco-heating products with traditional cigarettes. ‘This is the first study to use the Bhas assay to compare tobacco and nicotine products, and it demonstrates the potential for its future application as part of a product assessment framework,’ says Breheny.
Assessment of tobacco and nicotine products has traditionally involved genotoxicity tests, which evaluate initial DNA damage that can lead to cancer. Such tests indicate that e-cigarette vapour, in contrast to cigarette smoke, does not cause mutations and DNA damage. Using the Bhas 42 assay allows for increased understanding of potential carcinogenic risk.
Previous research conducted by British American Tobacco has shown that Vype ePen vapour contains around 95% less toxicants - in terms of the 9 harmful components the World Health Organisation recommends to reduce in cigarette smoke (Chem. Res. Toxicol, DOI: 10.1021/acs.chemrestox.6b00188) compared to cigarette smoke from a reference cigarette.
Many in the public health community believe e-cigarettes offer great potential for reducing the projected public health impact of smoking. Public Health England, an executive body of the UK Department of Health, published a report saying that the current expert estimate is that using e-cigarettes is around 95% safer than smoking cigarettes. The Royal College of Physicians have said that the public can be reassured that e-cigarettes are much safer than smoking and that they should be widely promoted as an alternative to cigarettes.
Notes to Editors