Verified: formaldehyde levels found in the NEJM study were associated with dry puff conditions. An update

By Dr Farsalinos

As mentioned in my previous comment about the formaldehyde study published in NEJM, it is very important to identify which vape atomizer was used and what energy levels (watts) were applied to the atomizer in order to understand whether the findings were associated with overheating. As I calculated, based on the consumption reported by the authors, I considered 3.3 volts as being about 7 watts and 5 volts being 14-16 watts. It seems that I was pretty close.

According to a post on Reddit, the authors used a top-coil CE4 atomizer and an Innokin VV V3.0 battery. The Reddit user has forwarded the email response of the study author to me, so I have verified the content of the response and the equipment used (I have also sent an email myself to the authors, and I am expecting their response). My predictions in the previous comment about the overheating possibility have been completely verified, while I was quite close in my calculations about the wattage levels applied to the atomizer.

I should first mention that i have personal research experience with the use of top-coil atomizers. I tried to use a very similar top-coil atomizer in my study evaluating plasma nicotine levels from e-cigarette use. In that study, we used an EVIC e cigarette battery set at 9watts. Unfortunately it was impossible for most vapers to use the top-coil vape atomizer and puff at their preferred conditions, due to dry puff taste which they could not withstand. Only a small minority who were taking very short puffs were able to use this atomizer at 9 watts. So, I had to change the atomizer to a bottom-coil EVOD, which worked quite well at 9 watts. In fact, the average puff duration of the participants in that study was 3.5seconds. So, the top-coil atomizer used at 9 watts became overheated at puff duration less than the 4 seconds used in the NEJM study. This is not the first time that an atomizer was proven to be insufficient and resulted in dry puff phenomenon which was immediately detected by the vapers; in our vaping topography study I specifically mentioned: “Originally our intention was to test another atomiser (“eGo-C”, Joyetech); however, some EC users experienced overheating of the atomizer and a phenomenon known as “dry-puff” (unpleasant, burning taste caused by insufficient supply of liquid to the resistance so that evaporation rate is higher than liquid supply-see the Discussion section for more details). They had to lower the puff duration and increase the inter-puff interval in order to avoid this phenomenon. In response to that, the eGo-C was substituted with “Epsilon” and participants were asked to come back for recordings with the new atomizer. All recordings with the eGo-C atomizer were discarded”. The authors of the NEJM study should have read our study and should have known about the existence of this phenomenon.

According to the Reddit post and author’s email, the vape atomizer had a resistance of 2.1 Ohms. This means that at 3.3 volts, the energy delivery was about 5.5 watts and at 5 volts it was 12 watts. It is more than obvious that the findings of very high levels of formaldehyde are a result of overheating. Lack of experience on e-cigarettes and no contact with vapers can result in such erroneous and unrealistic results, which can create confusion and misinformation both in the scientific community and among users and potential users of e cigarette. Finally, it is extremely important that every study evaluating vapor chemistry from e cigarette should mention in detail the equipment used.


E cigarette facilitate smoking cessation, new evidence shows

Do e cigarette help smokers to quit? Yes, but there is more to the story.

New Cochrane review finds emerging evidence that smokers who use electronic cigarettes can stop or reduce their smoking.

The first Cochrane review on this subject published today in the Cochrane Library gives some early insights in to vape as an aid to stopping smoking and reducing consumption. The review draws on two randomised trials and found that while nicotine containing e cigarette were more effective than electronic cigarettes without nicotine (placebo) in helping smokers kick the habit, the results need to be confirmed by more studies. Smoking is a major global health problem, is costly and is highly addictive. Despite many smokers wanting to stop, few succeed in the long-term. One of the most widely used strategies to help combat the cravings associated with nicotine addiction is to deliver nicotine by patches and chewing gum.

E cigarette have been around in some form for a number of years but recently their popularity has increased substantially. Unlike chewing gum and patches, they mimic the experience of cigarette smoking because they are hand-held and generate a smoke-like vapour when used. They provide smokers with a nicotine ‘hit’ and help to recreate similar sensations of smoking without exposing them or others to the smoke from conventional cigarettes. They are used by many smokers but little has been known about how effective they are at helping people to stop, nor their long term effects.

The team of researchers from the UK and New Zealand found two randomised trials that had analysed data from 662 current smokers. The researchers looked at the effects of e cigarette on quit rates and the number of people who were able to reduce the number of cigarettes they smoked by at least 50%. They also looked at any adverse effects reported by electronic cigarette users. The team also considered evidence from 11 observational studies.

The results show beneficial effects of electronic cigarettes, but are limited by the small number of trials and limited sample of people who were analysed in the studies. About 9% of smokers who used vape were able to stop smoking at up to one year. This compared with around 4% of smokers who used the nicotine-free electronic cigarettes. When the researchers looked at the data on reducing cigarettes in people who had not quit, they found that 36% of electronic cigarette users halved the number of conventional cigarettes. This compared with 28% of users who were given the placebos. Only one of the trials looked at the effects of electronic cigarettes compared with patches and this suggests similar efficacy of the two treatments. No serious adverse effects occurred over short to mid-term electronic cigarette use.

Author, and Professor of Clinical Psychology Peter Hajek, commented ‘Although our confidence in the effects of e cigarette as smoking cessation interventions is limited because of the small number of trials, the results are encouraging. Both trials used vape with low nicotine delivery and it is likely that more recent products are more effective as previous research suggests that higher and faster nicotine delivery facilitates treatment effects. Several ongoing studies will help to answer the question more fully.”

Author, Jamie Hartmann-Boyce said, “electronic cigarettes have become popular with smokers who want to reduce the risk of smoking. None of the studies in this review found that smokers who used vape short-term (2 years or less) had an increased health risk compared to smokers who did not use electronic cigarettes. We did not find any evidence from observational studies that people who used electronic cigarettes at the same time as using regular cigarettes were less likely to quit smoking. Findings suggest electronic cigarettes with nicotine help people stop or reduce smoking when compared to electronic cigarettes without nicotine, but more studies are needed.”

Cochrane’s Editor in Chief, David Tovey said this is an important study. “This review provides a timely reminder of the challenges faced by smokers who find it hard to stop smoking. The results so far need to be strengthened with further comparisons between electronic cigarettes and other traditional ways of stopping smoking such as chewing gum and patches, and evidence on long term safety.”