Jacques Le Houezec, Konstantinos Farsalinos, Jean-François Etter and Riccardo Polosa were on stage at Vapexpo 2016 to highlight current trends in e-cigarette research.

Visitors attending a scientific conference at Vapexo 2016, Paris.
Visitors attending a scientific conference at Vapexo 2016, Paris.
“The message I want to pass to vapers is that your consumption level defines the risk: the more you consume e-liquid, the more you will be exposed to toxicity, nicotine is no danger. Direct lung inhalation is pleasant but a risky pattern. At least you are aware about the risk”.Dr K. Farsalinos
Source K. Farsalinos, Vapexpo 2016.
Source K. Farsalinos, Vapexpo 2016.

Konstantinos Farsalinos comes back on the recent scientific publications published in 2016 that shacked the opinion. As always, he tries to debunk science. One of his first observations is that there is an increasing number of publications dealing with the e-cigarette compared to the previous years. And among those publications, an increasing number also report misleading information.

In his talk, he will address chemical studies (aldehydes, dry puffs, outdated devices, flavorings), toxicological studies (dose of exposure), clinical studies (focus on irrelevant animal studies) and examine the different means through which e-cigarettes can be harmful.

Chemical studies

Aldehydes: Formaldehyde and acrolein

Going back to 2013, scientists were aware that aldehydes (among which formaldehyde) were emitted by e-cigarettes. In this continuity, the same researchers demonstrated the next year that the voltage is playing an important role in the emission of aldehydes. Furthermore, the devices that were used for such studies are outdated compared to what vapers are using at the time the publication is released to public.

In the New England Journal of Medicine Letter, the authors calculated that over a lifetime, cancer risk with using e-cigarette could raise by 5-15 fold compared to the risk for regular smokers. Dr Farsalinos and his team addressed this question and identified that dry puffs were probably the cause of such high levels.

The researcher does not exclude the presence of aldehydes in e-cigarette emissions but dry puffs are peculiar conditions that generally do not happen when vaping, or at least that vapers can easily identify and can avoid.

Source K. Farsalinos, Vapexpo 2016.
Source K. Farsalinos, Vapexpo 2016.

The association between device power and aldehyde concentration was established recently by a team in Italy which confirm that the risk of developing cancer is much less than whas was initially thought. Furthermore, the relationship is not linear between the presence of aldehydes and power, which means that at the time vapers realize that something is changing in the taste of vapor, the levels are still very low.

Source K. Farsalinos, Vapexpo 2016.
Source K. Farsalinos, Vapexpo 2016.

The research team leaded by K. Farsalinos decided to replicate the original study by M. Goniewicz and to include humans in the protocol, the sole detector able to identify, with his taste, the occurence of dry puffs. They gradually increased the voltage in order to initiate dry puffs and asked the participant their impressions regarding the taste. They found that starting at 4.0 V, dry puffs may occur with the CE4 they were using, setting the limit of normal use until 4.0 V.

Source K. Farsalinos, Vapexpo 2016.
Source K. Farsalinos, Vapexpo 2016.

Liquid consumption was measured depending on the voltage and the authors found a positive correlation between the two. The observation that makes the researcher at this point is that increasing the voltage of a device drastically increases the risk by combining the non-linearity effect on aldehyde production and the exposure to more harmful compounds due to the larger volume of e-liquid consumed: they found that the levels are 7 to 8 times higher at 5.0 V compared to 4.2 V.

The danger upon exposure to formaldehyde has to be relativized, however, since the compound is found everywhere in our environment. The WHO has set the upper limit of formaldehyde in clean indoor air to 2000 μg/day, which is only three times lower than what inhales a vaper in Farsalinos’ experiment.

The orator recalls of the Harvard study about diacetyl and acetyl propionyl. He notices that the authors failed to mention that diacetyl was also present in tobacco smoke and has never posed to smokers any health safety issue at this level of exposure.

Flavors: Diacetyl

Source K. Farsalinos, Vapexpo 2016

The differences observed in emitted diacetyl is due to the nature of the e-liquid itself and, especially, the flavorings that are combined to obtain the right taste. On this point, the author believes that such harmful compounds must be removed completely from e-liquids since some substitutes exist with a lower toxicity.

Toxicological studies

Source K. Farsalinos, Vapexpo 2016
Source K. Farsalinos, Vapexpo 2016

K. Farsalinos comes back on a recent study carried out on mice models that claimed the e-cigarette, through nicotine, could cause COPD. He ironises on the difference between mice and humans, especially from a metabolic point of view. Mice are much more efficient at metabolizing nicotine compared to humans and the degradation product (cotinine) is also eliminated at a much faster rate. Hence comparing mice to humans, in this field, is not realistic.

The effect of nicotine on blood vessels was also reviewed by the specialist. In vitro experiments generally expose the cells to levels that should be lethal to a normal adult, he explains.

Clinical studies

A few studies addressed asthma but ignored that Ricardo Polosa carried out clinical studies that showed “collateral benefits” from vaping on human health.

In the case of aortic stiffness reported from a conference presentation by the Sun, in England, K. Farsalinos recalls that the acute conditions of the study are not compatible with relevant observation and that nicotine is no more harmful than caffeine, in fact. It is not surprising that false positive results are obtained in such bad conditions, believes the researcher. The same results are observed when nicotine gums are given to patients and also when they are given coffee.

The cardiologist recalls that he measured improvements in the heart function after four weeks of smoking cessation, which is the normal case when avoiding acute effect of nicotine exposure. He recalls that in no way this could be taken into consideration for evaluating long-term effects of vaping. The benefits of vaping on the heart function are pointed out from R. Polosa’s ECLAT survey on quitters and reducers.

The debate on nicotine is, by itself misleading

It is well-known that nicotine is not a major risk factor to any smoker. -K. Farsalinos
Vapers generally misconceive some basic aspects of nicotine consumption with e-cigarettes, declares the scientist. But the more vapers consume e-liquid, the more they are exposed to harmful or potentially harmful molecules it contains: toxins (e.g. aldehydes) and flavoring chemicals (e.g. diacetyl).

“A vaper consuming 12 ml/day is absorbing more formaldehyde than a smoker smoking one pack/day.” K. Farsalinos, Vapexpo 2016

What appears important in K. Farsalinos’ studies, is that increasing the consumption of liquid is increasing the risk. It is for example what happens with new patterns, especially direct-lung pattern of use.

Source K. Farsalinos, Vapexpo 2016

Compared to mouth-to-lung vaping, one direct-lung puff consumes 5 times more e-liquid. This pattern is generally associated to lower nicotine levels than traditional vaping style, to reduce irritation because of the higher consumption of liquid.

Jean-François Etter, Global Health Institute, Geneva, Switzerland.
Jean-François Etter, Global Health Institute, Geneva, Switzerland.

The researcher recalls Paracelsus principle of toxicity:”the amount of exposure, the dose, defines the toxicity”. Reducing the nicotine level but increasing the consumption is useless with regard to the nicotine, as demonstrated by Jean-François Etter when studying cotinine levels. J.-F. Etter qualified this effect a “compensation mechanism” for nicotine. In revenge, increasing e-liquid consumption exposes to more toxins. Hence, DL inhalation is a more risky pattern than MTL vaping, wanted to recall the clinician for the sake of clarity.

Jacques le Houezec mentions that there is currently a movement among e-liquid manufacturers and among the vapers, themselves, to reduce nicotine strength. The obvious issue is to get exposed to more toxins but the tobacco expert recalls that the risk is also to relapse into smoking.

“Vapers, don’t go too fast, don’t lower too much your nicotine strength, nicotine is not harmful in itself”Dr J. Le Houezec

Questions to K. Farsalinos

Konstantinos Farsalinos
Konstantinos Farsalinos

“What are the next steps in your research?”

The researcher reveals they have carried out a study on metals emitted from tank atomizers. In this study, they compared the emission of metals from tank atomizers and (disposable) cigalikes where the e-liquid is stored in contact with a metallic cartomizer during months before use which increases the risk of corrosion in the device.

Their results indicate that the levels of metals in emitted vapor were in the range of part per billion (ppb), meaning they are extremely small.

Aldehydes are addressed by his research team and also the comparison with the new harm reduction products proposed by tobacco companies like the IQOS. This is important, he thinks, to address the two different devices, e-cigarette and tobacco heating systems, that are “sold” as harm reduction products to smokers willing to stop smoking.

Finally, the Eurobarometer data are exploited again with a focus on daily e-cigarette users. A publication written in collaboration with Jacques Le Houezec.

“Could the fact that vapers try to reduce their nicotine level be pushed by the maximum nicotine strength defined by the TPD?”

K. Farsalinos believes that current e-cigarette models are efficient enough at delivering nicotine and may allow smokers to transition to vaping. As an illustration, the specialist says that twice as much nicotine can be delivered with ten puffs of an e-cigarette as with one tobacco cigarette .

In return, K. Farsalinos ask the public to remember when they started vaping, how much they consumed of e-liquid and to compare the numbers with their actual consumption. From his observations, the volume is likely three times, now. And this increase is driven by the new trends impulsed by the vaping industry. New vaping patterns like DL inhalation add other satisfaction levels to vapers after their transition from smoking with MTL, but this DL inhalation pattern is not needed to stay off cigarettes, it’s pure pleasure.

That’s not right, that’s what they tell us! -R. Polosa
Many consumers have been “educated” by tobacco control and media to think that nicotine is the enemy of the smoker and it could be the same for vapers, adds Riccardo Polosa. The cultural issue of trying to reduce nicotine at all cost has become a motivational tool, for vapers, a challenge to gain more in health. .

K. Farsalinos observe that the strength he vapes, 18 mg/ml, could no longer be found in the stands of the Vapexpo event. And this is the strength he has been vaping since he started with e-cigarettes.

The Vaping Post already identified the overall decrease of the offer in nicotine strength as a potential public health issue if this tendency is maintained by harsh regulations that make it expensive and burdensome to notify and register a full range of nicotine strengths for each flavor.

To go further on the marketing of nicotine with new vaping patterns:

Popularity of subohm kits drags juice sales to low nicotine strength


Book your ad here


    • I Think Yes ! If you consume 12 at 15ml per Day this equivalent to 20 or more cigaret about the Diacethyl and Formaldehyde Harmfull Toxin for Healt to be good vaping just go an Bridge to stop Smoking and Quit Vaping if necessary just vape a little…for don’t return to real cigaret… Long term of Vaping with up 10ml consumption or more in Direct to lung… Just Done Bad result for the Human body after long Years of Vaping…it’s potentially Risky

    • Hi Rok, it depends on which parameter you consider.
      It should be roughly the case for aldehydes like formaldehyde.
      But compared to cigarettes, you don’t inhale as much carbon monoxide or tar, nitrosamines and other toxic and carcinogenic molecules when vaping.
      In turn, depending on which e-liquid you consume, you may inhale some of the toxics that come from the flavorings, which science is trying to identify and eliminate.

  1. Reducing the nic level encourages vapers to consume more ml’s of liquid. That works for juice companies but may not be the best tradeoff for health. May be it’s better to keep nic levels higher so there is lower daily ml’s.

    • Yes, for sure, and leave your body do the rest.
      For that, the human body is awesome, it is able to regulate the level of nicotine it needs. If your body is in demand, you will feel the need to vape more. It it is starved with nicotine, you won’t feel the craving effect and delay the next puff until your body warns you that it becomes an emergency.
      Of course, it works better if you’re alone than if you are surrounded by many vapers or smokers who are tempting you…

  2. So he’s saying that nicotine is fairly harmless, but the flavoursome liquid that it’s in is the bit that could harm you.
    That’s why I vape 36mg unflavoured VG. To minimise harm to my lungs, after 50 years of smoking.

  3. Ok, so I need some help understanding this.
    These graphs have me and my husband debating and we need someone to help
    explain this to us.

    If a person vapes at 4V, according to graph 4 “Aldehydes According To
    Power” they are getting very little Aldehydes (around 100 molecules of
    toxins total). But then when you look at the graph 7 “Formaldehyde
    Emissions According to Liquid Consumption” and are consuming 3ML you are
    taking in around 600 molecules of toxins. So, graph 4 is showing less than 100
    molecules of toxins and graph seven is 600 molecules of toxins. How can this

    I understand the power and e-liquid are two different studies, but why didn’t
    K. Farsalinos combine the two on one graph? Maybe I am overlooking
    something and there is a simple answer…

    Also, my husband is saying the full PG should have very little aldehyde
    emissions due to its purity. I am not sure of this…I thought heating any
    chemical would change its makeup and cause the toxins whether you are using PG
    or VG e-liquid. Can someone shed some light on these questions?

    I am a full time vaper by the way!

    • Hi Lindsey, I will try to help you see clearer.

      There are two aspects of the problem, a power aspect and a volume aspect.
      The graph “Aledhydes according to power” indicates the non-linearity of the emission with intensity (or power) with a slow regime of emission under 4 V and a higher regime above this value. By the way the units that are displayed on the graph “Aledhydes according to power” are nanograms of the given molecule over 50 puffs (relative consumption).

      In revenge, on the graph “Formaldehyde emissions according to liquid consumption”, the Y-axis shows absolute consumption in micrograms of formaldehyde, with micrograms x1000 than nanograms. The volume effect makes that the rule of three applies with the aldehydes emitted: You inhale twice as much aldehydes if you multiply your consumption by two. Here, 423.8×4=1695.2 when your consumption increases from 3 to 12 ml.
      The point that is made by K. Farsalinos, here, is that vaping 3 ml per day (what a regular MTL vaper does, on average) puts you in safer conditions compared to smoking a pack a day with respect to formaldehyde. In contrast, multiplying your consumption of e-liquid by 4 increases your risk with respect to aldehydes and exposes you to a higher risk than smoking a pack a day.

      Vaping is like driving: If you drive 25 mph in daylight on a straight road, sober, that you wear your seatbelt, it is relatively safe for yourself. Now driving 100 mph in the fog on a narrow road with turns, drunk, without your seatbelt is just more dangerous although you are using the same car.

      It is a question of behavior!

      It is exactly the message that K. Farsalinos delivers. Using your e-cigarette with 18 mg/ml nicotine and vaping 3-4 ml of e-liquid per day is a normal behavior and much safer than decreasing your nicotine strength and increasing your e-liquid consumption. It is also much safer than increasing the power to produce bigger clouds that you inhale Direct-Lung for the fun of it.

      Now, I am afraid that your husband misunderstood what drives aldehyde production in vaping.
      Aldehydes are simple organic molecules produced when the bigger organic PG or VG are oxidized (organic, here, is the chemical origine, as opposed to mineral, and has nothing to do with the biological origin).
      This oxidation occurs when PG/VG are heated in presence of oxygen.

      There are basically two ways to concur to lower aldehyde emission, and they have nothing to do with purity.
      First of all, temperature: Increasing the temperature also increases the risk of producing more aldehydes (as shown by K. Farsalinos on graph 4 with its non-linear behaviour).
      Second: The presence of combustion residues. Keep your setup as clean as possible. The risk of producing aldehydes also increases when “caramel” is formed around your coil and burnt again and again when you fire up your e-cigarette.

      I hope it helps.

      • Jerome, thank you so much for taking your time to provide this information! This is a huge help to me. I had to read it twice, but the car comparison did it for me. Many thanks!

  4. In South East Asia where vaping is heavily suppressed, but smoking is encouraged, there are still vaping hobbyist stores about. They rarely sell any liquids above 6mg nicotine, and supplement the low nicotine with incredibly powerful, high tech devices. Naturally the amount of liquid consumed is so high that vaping is much more expensive than smoking. It’s quite crazy.

  5. So I usually vape at around 105 watts on a .2 ohm dual clapton coil which reads out to about 5.20 volts. I vape 6mg nicotine and I vape alot….so your telling me I would be better off just going back to smoking a pack of cigarettes a day?

    • Not at all.
      By vaping, you considerably reduced exposure to CO and Tar (and also dependence to Big Tobacco products). But your vaping behavior apparently sets your level of exposure to aldehydes at a higher level, probably very close to smoking a pack a day.
      One has to differentiate the recreational use of an e-cigarette to its use to fight craving for combustible tobacco.
      To fight craving for cigarettes, experts like Konstantinos Farsalinos or Jacques Le Houezec recommend vaping 18 mg/ml e-liquid at a reasonable power to avoid extra-emission of potentially harmful molecules and not to exceed 4 ml/day e-liquid consumption… Their experience demonstrate that it may be enough and, if not, they recommend to combine vaping with the use of nicotine patches or gums. The body is able to self-adjust vaping patterns to adapt nicotine level in the bloodstream. Nicotine is not more harmful than caffeine and, if your body is used to a certain dose, no need to starve it.
      Now, everybody is free to make use of an e-cigarette in a recreational way. We just warn you that recreational behaviors like power-vaping or vape-tricks do not represent the same risk levels as simply vaping.
      The message, here, is that the dogma that says a vaper should reduce his/her daily nicotine intake at all costs is nonsense and dangerous. Increasing e-juice consumption because of reducing nicotine strength is unfortunate because it’s loosing part of the benefit of vaping, but it is a collateral damage of the recreational use of an e-cigarette.

  6. There is little doubt that vaping at high power levels is hazardous and that high power vaping has become far more common since the NEJM letter was published two years ago. Since the majority use of the devices is now harmful it could lead to a ban of ALL the devices even the ones used a low power. Big Vaping has done everything it can to get vaping banned. A pox on them and all the power-vaping lunatics that helped increase the risk.

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