from IVVA (Irish Vape Vendors Association) – http://www.ivva.ie/latest-news/flawed-study-and-questionable-pr-becomes-news/
It is unfortunate that ‘negative’ media stories about vaping garner a lot more clicks and shares than ones which tend to be more balanced and accurately reported. One thing most casual readers would hope however, is that what is contained in the press release which gets sent out to journalists does indeed reflect the study findings, and that the data and its implications have been communicated honestly and accurately.
So it certainly disappointing that a study which came to light on Tuesday has elicited some highly alarmist headlines. Although the research was conducted in November, its release this week seems to perfectly coincide with the exact time of year that many smokers will perhaps be thinking of looking for an alternative as part of their new resolutions.
‘Scientists warn e-cigarettes could cause cancer’
‘E-cigarettes may be ‘no better’ than smoking regular cigarettes, warn scientists’
‘E-cigarettes are not safe! They can cause cancer too’
‘E-cigarettes are ‘no better’ than traditional cigarettes, say scientists’
So what lies behind the headlines, what was the study looking at, and was the media frenzy warranted?
According to the press release,
…a lab team at the Veterans Affairs San Diego Healthcare System tested two products and found they damaged cells in ways that could lead to cancer. The damage occurred even with nicotine-free versions of the products.
“Our study strongly suggests that electronic cigarettes are not as safe as their marketing makes them appear to the public,” wrote the researchers, who published their findings in the journal Oral Oncology.
…created an extract from the vapor of two popular brands of e-cigarettes and used it to treat human cells in Petri dishes. Compared with untreated cells, the treated cells were more likely to show DNA damage and die.
Dr. Jessica Wang-Rodriquez, one of the lead researchers concludes:
“Based on the evidence to date,” she says, “I believe they are no better than smoking regular cigarettes.”
The study tells us that ”E-cigarette vapor was pulled through media using negative pressure, and the resulting extract was filter-sterilized with a 0.2µm pore-size filter before treating cell cultures.”
However, as Tom Pruen, Chief Scientific Officer for ECITA points out:
Here’s what is not described in the method:
- Hardware – No mention is made of what hardware was used to generate the vapour. No mention of what design the hardware was, its resistance, or how much power was supplied to it.
- Topography – How long were the puffs? How long between puffs? How many puffs were taken per cartomiser/tank? Was the number of puffs plausible for the design?
- Were the emissions generated in a sensible, realistic way, or was there dry burning (leading to huge emissions of carcinogens – an effect described in the literature back in 2013)? This could have been easily established by conducting an analysis of the vapour condensate for carbonyls, but this was not done.
Effectively, this leaves us with no information at all on the sampling methods, making this research incomplete and unrepeatable. That is not how science is supposed to be conducted.
As regards the fact that this particular type of cell was used, there has been some criticism of the use of cell studies to look at whether results can be directly translated into similar effects in humans. Dr Farsalinos from the Onassis Cardiac Surgery Centre in Athens said when looking at a different study that: ”In the majority of cases, the protocols and experimental procedures are irrelevant to human effects.”
So in comparing the effects of tobacco smoke and e-cigarette vapour, were the two protocols of exposure to the cell cultures comparable, so that an accurate comparison between the amount or rate of cell death observed could be made?
Not at all.
From the study itself:
“Treatment media was replaced every three days with 1% e-cigarette extract. Because of the high toxicity of cigarette smoke extract, cigarette-treated samples of each cell line could only be treated for 24 h.”
Tom Pruen looks at this more closely:
So the cells were being constantly exposed to the vapour condensate for periods of multiple days, with the solution refreshed every 3 days, but only for 24 hours to cigarette smoke condensate because it was too toxic.
Despite the massive difference in exposure, the cigarette smoke extract scored as high or higher on most of the measured outcomes:
Read full article at http://www.ivva.ie/latest-news/flawed-study-and-questionable-pr-becomes-news/