Bud Mullen 9 mins · . PUT THIS IN YOUR PIPE AND VAPE IT! Hidden Formaldehyde in E-cigarette Aerosols – some questions and concerns 21 January 2015 Dear Dr Peyton, Dr Pankow I write with reference to the forthcoming letter “Hidden Formaldehyde in E-cigarette Aerosols” to be published in the New England Journal of Medicine, under a 5pm EST 21 January 2015 embargo. Given the great potential for these findings and the related cancer-risk calculations to cause damaging confusion and fear among smokers and vapers, I would be grateful if you could clarify the following: 1. What care was taken to ensure that the puff regime used was a reasonable proxy for human use and exposure? The letter does not detail any attempt to calibrate the puffing regime used in the experiment to match real-world vaping behaviour. The levels of formaldehyde detected suggest it was a highly unrealistic regime. 2. What, if any, precautions were taken to avoid measuring and reporting on ‘dry puff’ conditions – i.e. through use of such high voltage and high intensity puffing that the coil becomes so hot that it creates vapour of such acrid taste and harshness that human users would not use it in that way? It is under these conditions that high levels of formaldehyde and related compounds would be expected to form – but no human would ever be exposed to them. Humans have control over the sensory experience that puffing machines do not. 3. In making your newsworthy claims about cancer risk, what confidence do have that the puffing regime used appropriately represents human vaping behaviour, and therefore human cancer risk? There is a danger that naive reporting of your findings will characterise these risks as integral to vaping products, whereas they are a feature of the operating regime, which appears to be extreme in this case. These findings are only appropriate as cancer risk communication if the operating regime is realistic. However, the letter does not detail how you have assured this is the case – and no caveat has been provided to highlight that serious and probably fatal weakness in this work. 4. In the calculations of cancer risk, it is assumed that “inhaling formaldehyde-releasing agents carries the same risk per unit of formaldehyde as the risk associated with inhaling gaseous formaldehyde“. Can you provide a citation to support this assumption, given that the attention-grabbing findings in the letter rest entirely on it? As you will be aware, formaldehyde-releasing preservatives are used as an alternative to formaldehyde in many preparations for safety reasons. 5. The letter claims that the incremental lifetime cancer risk associated with long term vaping “is 5 times as high … or even 15 times as high … as the risk associated with long-term smoking“. Can you clarify that this comparison refers to only that part of the smoking cancer risk that arises from formaldehyde exposure? In order not to confuse readers with the idea that long term vaping may carry 5-15 times the risk of smoking, would it be possible to provide an appropriate context: for example, what proportion of the smoking cancer risk is attributable to formaldehyde? I think it is a small fraction of the total, and it would have been prudent to state this. Formaldehyde is not the most important carcinogen in cigarette smoke by some distance and just one of many. The Surgeon General’s 2010 report Chapter 5 provides a useful guide, but does not go as far as your letter does in attributing cancer risk to individual carcinogens. The Surgeon General also reminds us that: Aldehydes such as formaldehyde and acetaldehyde occur widely in the human environment and are endogenous metabolites found in human blood It is possible therefore that the estimation of cancer risk from formaldehyde is more complicated than your simple model allows for. To be more direct, I am concerned that: •This study uses a completely unrealistic puffing regime to create the conditions in which formaldehyde forms with no attempt to calibrate the machine to reflect realistic human use. •That it presents results from extreme and unrealistic operating conditions which are then built into a ‘back of the envelope’ calculation of cancer risk. •That this contrived and artificial cancer risk is misleadingly compared to real human cancer risks associated with smoking. •That the statements about vaping having 5-15 times the incremental cancer risk associated with smoking are provided without context and could easily be misread as implying that vaping is more dangerous than smoking. It would not be the first time that misreporting of formaldehyde findings have created this impression. •This study may repeat the harm done through mischaracterisation of ‘light’ cigarettes by use of unrealistic puffing regimes that did not reflect real human behaviour. The same is likely to apply here, but instead of understating risk of a harmful product, the effect will be to grossly overstate the risk of a relatively benign product – with equally damaging results. Many smokers have a great opportunity to switch from smoking to vaping, and to reduce their incremental risk of disease by 95-99%. However, studies like this and the reporting that has followed, are gradually persuading smokers that e-cigarettes are much more risky than they are, and that they might as well continue to smoke. A study published in 2014 found the following: In 2010, 84.7% of smokers surveyed believed e-cigarettes were less harmful than traditional cigarettes, but according to this new study in 2013, that number dropped to just 65% [link]. This is a trend that should shame the public health community and the academics that are fuelling consumers’ misunderstanding with misleading studies that misrepresent risk. I am sure it is not your aim to protect the cigarette trade and prolong the epidemic of smoking related disease, but it may well be the effect. I hope you will take great care to ensure your findings are described in context and with appropriate caveats about whether these results are realistic for human exposure and that the calculations of cancer risk are remotely meaningful.. Yours sincerely Clive Bates Counterfactual London / Harare
Posted on: Fri, 23 Jan 2015 22:29:11 +0000
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