- Saturday, 14 September 2013 06:01
Basic science principles 60 Millions de consommateurs should know before making claims
By Dr Farsalinos
Unlike my comments, which are always based on science and research principles and are always supported by data published in peer-reviewed publications (I always provide links for every information given), the French magazine continues to distort science and make claims that cannot be supported by the evidence and the data they provide.
In an update of their article, they provide an answer to my previous comment by “clarifying” that their conclusion was that certain e-cigarettes may be more toxic that certain tobacco cigarettes. This conclusion, as I have already mentioned in my previous analysis, can be made only if you select the best result from a tobacco cigarette with the worst result from an electronic cigarette. However, they still fail to understand that this is incompatible with basic principles of science and research.
Imagine that I am testing the effects of tobacco cigarettes in one patient. And I find that heart function or coronary circulation improves after smoking one cigarette (it can happen and it is a chance finding). However, the study included 40 more patients, in the majority of which heart function and coronary circulation deteriorated after smoking. The mean values have clearly shown that there is deterioration in the measured parameters post-smoking. Is it legitimate to use the single patient with improvement and state that tobacco cigarettes are beneficial? Of course not. Is it legitimate to say that this patient will benefit from smoking? Of course not! Take another example. We know that 90% of lung cancer cases are smokers. However, out of the whole smokers population, only 1 in 7 will develop cancer. Should we just take the example of 6 who will not get cancer and say that smoking does not cause lung cancer? This is not how science works, and if you don't know such basic principles you should ask for advice before making claims about the results of research.
Focusing on e-cigarette experiments, I have previously explained the unpredictable and chaotic nature of the evaporation process (it is similar to the burning process of tobacco cigarettes). That is why it is impossible to get any valid conclusions by testing a single device once. Goniewicz and coworkers tested 12 different devices; each device was tested 3 times. In the table of the results from each device (available in the full-text version of their published paper) you can see that the variability in measurements from 3 repetitions was 10-45%. This means that the same device when tested 3 times shows a huge difference in results. Therefore, repeated and multiple testing is an absolute necessity. But you do not choose the one result that suits your predisposed opinion. In their final conclusion, the authors provided the range of findings from all measurements and compared it with the range of findings of tobacco cigarettes. This is how proper science works. It would have been even better if they had tested 3-5 cigarettes at the same experiment and provide mean values. Then, the mean of the measurements would be directly compared. In any case, it is scientifically unsound to choose one sample (e-cigarette) and compare it with another single sample from another product (tobacco). Extreme findings (lowest or highest) are considered chance findings.
The French study provided us with a table with the results of each sample tested. You can see that when testing the same liquids with a nicotine-free liquid results are different. You may say that nicotine has an effect on the levels of chemical produced, however the differences have absolutely no pattern. In two cases, levels of chemicals were lower; in another case it was higher. This is not due to the presence of nicotine but due to the variability expected from repeated measurements. Even if they tested the same device with the same amount of nicotine twice, they would still find significant differences in results. This is how science works. I explained that the procedure of evaporation, liquid supply to the wick and re-supply during activation of the device can never be reproduced in an identical way. Each puff will be different; each experimental session will produce different results. You need to make multiple measurements and report the mean values.
I understand that the journalists of a consumer magazine may not know these principles. However, this is not an excuse. They assigned the study to a specialized laboratory. They should have been informed by the laboratory that the way they report the results is invalid and scientifically unsound. Did they ask for advice from any other scientist about the findings and how they should be interpreted? I am sure a lot of people would be willing to properly inform them about the fundamental mistakes in their approach. I would be happy to do that (without asking for any kind of compensation of course). The journalists should have known that it is a paradox to say that their findings are similar to Goniewicz but their conclusions are exactly the opposite. It is really strange that, after all this publicity, they still insist on their original statement that some e-cigarettes may be more toxic than some tobacco cigarettes. Their results simply DO NOT SUPPORT THAT. This is absolutely clear for anyone understanding basic principles of science. However, the problem is that smokers and e-cigarette users (who have no idea about how research should be done and reported), have certainly been intimidated by reading such statements. And this is why the behavior of the French magazine is inexcusable, irresponsible and dangerous (hard words, but this is the truth). They have to realize that several e-cigarette users have already thrown away their e-cigarettes and have relapsed to smoking after reading their articles. Moreover, several smokers who were ready to quit by using the e-cigarette have postponed (or, most probably, cancelled) their decision. Who will bear the ethical responsibility for this?
Dr Farsalinos is a researcher at Onassis Cardiac Surgery Center in Athens-Greece and at Medical Imaging Research Center, University Hospital Gathuisberg in Leuven-Belgium. He is actively involved in research on e-cigarettes’ safety and risk profile.