E-cig vapor does not induce genetic mutations associated with cigarette smoke exposure

November 4, 2016

E-cigarette vapour does not induce DNA mutations commonly observed with tobacco smoke exposures in lab-based tests.

Scientists at British American Tobacco used a method called the Ames test to compare the mutagenic potential of with that of vapour from Vype ePen, a commercially available e-cigarette. DNA mutations result in , which may be involved in the development of cancer.

The Ames test is widely used method that uses bacteria to test whether a given chemical or drug causes mutations in the bacteria's DNA. The standard test involves five . In this study, two of these bacteria were used Salmonella typhimurium strains TA98 and TA100, both of which are effective at screening 90-95% of potential mutagens. TA98 and TA100 have been used widely to assess tobacco smoke, but never for the assessment of freshly generated e-cigarette aerosols, until now.

Traditionally, the particulate matter in smoke is assessed, but this is only a small fraction of the tobacco smoke. To more accurately reflect real-life exposure, whole smoke was also tested. In all, the researchers tested both the particulate matter and whole aerosol of smoke from a reference cigarette 3R4F and vapour from Vype ePen.

To do this, they trapped particulate matter from smoke or vapour on a filter pad and then washed the pad with a solvent to produce a stock solution that could be diluted into various concentrations. They then exposed the test bacteria to the same concentrations of either smoke or vapour extract. They also exposed test bacteria to freshly generated smoke or e-cigarette vapour.

Exposure to smoke was seen to cause mutations in both bacterial strains in a dose-dependent manner - the higher the dose, the higher the mutation rate. Whole smoke took just 24 minutes to cause mutations. E-cigarette vapour extracts, gave no response, and whole vapour did not cause the bacteria to mutate, even after three hours of continuous exposure, which was comparable to the results obtained from air and untreated controls.

'These findings suggest that Vype ePen vapour does not induce the mutations observed on exposure to smoke,' said Dr James Murphy, Head of Reduced Risk Substantiation at British American Tobacco. 'This study adds data to support the growing evidence base that e-cigarettes have the potential to be significantly less harmful compared to cigarette smoke, though more research is needed' he said.

Many in the public health community believe e-cigarettes offer great potential for reducing the public health impact of smoking. Public Health England, an executive body of the UK Department of Health, recently published a report saying that e-cigarettes are 95% safer than cigarettes. The Royal College of Physicians have said that the public can be reassured that e-cigarettes are much safer then smoking and that they should be widely promoted as an alternative to cigarettes, but called for more research to be done on the potential long term effects of using e-cigarettes.

The results are published in Mutation Research/Genetic Toxicology and Environmental Mutagenesis.

Explore further: Human heart cells respond less to e-cig vapour than tobacco smoke

More information: D. Thorne et al, The mutagenic assessment of an electronic-cigarette and reference cigarette smoke using the Ames assay in strains TA98 and TA100, Mutation Research/Genetic Toxicology and Environmental Mutagenesis (2016). DOI: 10.1016/j.mrgentox.2016.10.005

Related Stories

Human heart cells respond less to e-cig vapour than tobacco smoke

May 4, 2016
New research has showed substantial differences in the way human heart cells respond to e-cigarette smoke and conventional cigarette smoke.

New scientific test delivers greater insight to inform future scientific studies on e-cigs

October 10, 2016
If you are a vaper, scientists want to know how you vape because understanding this is an essential first step to understanding how vaping products are used and the potential they may have to reduce harm caused by smoking.

Ames test adapted successfully to screen complex aerosols

August 26, 2014
The Ames test, a widely used method to determine whether a chemical has the potential to cause cancer, has been successfully adapted for use with cigarette smoke and other complex aerosols.

Nearly two-thirds of smokers also use E-cigarettes: CDC

October 31, 2016
(HealthDay)—Many American adults who use electronic cigarettes also smoke tobacco cigarettes, a U.S. Centers for Disease Control and Prevention survey reveals.

Study finds a new way that tobacco smoke can cause cancer

October 17, 2016
A recent study led by University of Kentucky researchers illuminates a new way that tobacco smoke may promote the development of lung cancer: inhibiting a DNA repair process called nucleotide excision repair (NER). The results ...

More evidence found on potential harmful effects of e-cigarettes

February 11, 2016
While e-cigarette use is increasing worldwide, little is known about the health effects e-cigarettes pose for users. A University of Louisville researcher is working to change that status.

Recommended for you

Gulf spill oil dispersants associated with health symptoms in cleanup workers

September 19, 2017
Workers who were likely exposed to dispersants while cleaning up the 2010 Deepwater Horizon oil spill experienced a range of health symptoms including cough and wheeze, and skin and eye irritation, according to scientists ...

India has avoided 1 million child deaths since 2005, new study concludes

September 19, 2017
India has avoided about 1 million deaths of children under age five since 2005, driven by significant reductions in mortality from pneumonia, diarrhea, tetanus and measles, according to new research published today.

Study suggests link between youth football and later-life emotional, behavioral impairment

September 19, 2017
A new study has found an association between participation in youth tackle football before age 12 and impaired mood and behavior later in life. The study appears in Nature's Translational Psychiatry.

Self-confidence affected by teammates, study finds

September 19, 2017
A person's confidence in their own ability varies significantly depending on who is in their team, according to new research from the University of Stirling.

Video game boosts sex health IQ and attitudes in minority teens

September 18, 2017
A videogame designed by Yale researchers to promote health and reduce risky behavior in teens improves sexual health knowledge and attitudes among minority youth, according to a new study. The findings validate the value ...

Two Americas: Seniors are getting healthier but most gains go to high-income whites

September 18, 2017
Older Americans report feeling dramatically healthier than they did 14 years ago but that good health isn't evenly distributed, with much of the gain going to the wealthiest, most highly educated and whites.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.