July 31st, 2014

Briefing: the case for e-cigarettes

Shorter briefingIn response to my longer briefing, sometimes people say: well could you please state the case more concisely?  So here is a shorter briefing, starting with a one paragraph summary…

The case for an enlightened policy on e-cigarettes

The outline of the argument:... e-cigarettes are proving to be a very valuable market based positive public health phenomenon, that consumers like and costs the state nothing. The danger is that clumsy regulation to address minor or implausible risks will destroy large parts of the market and leave the products less appealing to adult smokers. In that event,  we will end up with more smoking, disease and death than would otherwise be the case. The UK should champion a liberal market based approach with only light touch regulation.
In more detail…
1. Strong value proposition relative to smoking is a cause for optimism. E-cigarette and related products offer a successful new value proposition to smokers that has emerged since 2008.  They meet demand for recreational nicotine but also replacing behavioural and ritual aspects of smoking, while greatly reducing the risk of diseases, improving immediate welfare, reducing social stigma and saving money.  The health risks are likely to be at least 95% lower than smoking, and likely to be considerably less than that. We know this from the basic chemistry and physics and dozens toxicology studies. It does not require a 50 year cohort study to make an educated estimate of the health risk.
2. Widespread uptake by smokers and significant health gains already. About 2.1m people are now using e-cigarettes, and 700,000 of these are now ex-smokers (there were about 10m smokers in 2010, about 20% adults). Use among never-smokers is negligible (~0.2%). Given that the health value of quitting is estimated by DH economists at £74,000, the 700,000 switchers represents a huge health dividend (£53bn), achieved with no public money, no call on the NHS and no coercive laws or punitive taxes.  It is a disruptive consumer and market based phenomenon, and is has wrong-footed many in the public health establishment. We have seen this before with ‘snus’ in Sweden – nicotine taken as smokeless tobacco is the reason why Sweden has the lowest smoking rates in Europe by far (13% rather compared to 28% EU average in 2012) and hence much lowest rates of smoking related disease. Absurdly, snus is banned in the EU outside Sweden but serves as a reminder of how arbitrary and counterproductive EU public health regulation can be.
3. Negligible unintended consequences in reality.  A number health bodies have worried about e-cigarettes being a ‘gateway’ to smoking, or that because they make the life of a smoker less intolerable, the incentives to quit completely will be reduced and quit rates will fall. There are no signs of either of these hypothetical effects. Quite the contrary – youth uptake is very low and highly concentrated in existing smokers, where it may divert from smoking and hence be beneficial. Quit rates in the UK have picked up with the rise of e-cigarettes. There have been accusations that the industry targets children – these are unfounded and extremely unlikely given there is a huge smokers’ market to go for and that is where their value proposition works. There are also claims that certain flavours ‘target children’. Again highly unlikely – and based on a confusion about what adolescents are looking for – teenagers are more likely to seek out ‘adult’ flavours, than to emphasise their own childishness. However, many adults do like frivolous fruity or candy flavours.
4. The greatest threat to these highly positive public health developments is excessive or ill-fitting regulation. The products are already subject to general consumer protection legislation, and some light touch specific regulation would be valuable in building consumers confidence, protecting health and safety, and avoiding uptake by young people.  However, excessive or arbitrary restrictions, heavy burdens and costs can have a number of malign effects – essentially degrading the value proposition of e-cigarettes and in doing so, protecting cigarettes from competition, causing lower uptake and leaving more people smoking.  The proponents of ‘tough’ regulation never acknowledge this health risk or weigh it against the supposed benefits of their proposals.
5. The emerging UK/EU regulatory regime is likely to cause significantly more harm than good.  The EU/UK regulatory regime will start to bite in 2016 and will consist of the ad hoc provisions of the EU Tobacco Products Directive just agreed this year (the ‘TPD’) and the UK’s proposal to regulate e-cigarettes as medicines. UK is to allow both pathways to market (TPD and medicines).  Internationally, WHO has expressed intent to regulate e-cigarettes as tobacco products and subject them to the same controls used to reduce tobacco consumption.
5s. Problems with Tobacco Products Directive. In brief the main problems with TPD:
– a ban on most forms of advertising – wholly disproportionate and anti-competitive measure in a ‘single market directive’
– a limit on the strength of liquids (to 2% nicotine concentration), ruling out stronger liquids used by more heavily addicted smokers and those first switching – liquids of this strength are used by 25-30% of smokers
– a limit on container sizes that is unnecessary and unjustified
– bold warnings covering 30% of the packaging – disproportionate to risk and creating unwarranted fear
– a large compliance burden and heavy notification regime that will raise costs and rule out a large number of perfectly good SMEs and products
– members states are free to regulate/ban flavours – but these are integral to the value proposition
– despite overwhelming evidence of the beneficial effect of snus in Sweden the directive reaffirmed the ban on snus outside Sweden
5b. Problems with regulating as a medicine. In brief, the main problem with medicines regulation for e-cigarettes is that it is a strict and burdensome authorisation regime, requires pharmaceutical grade manufacturing and process controls and imposes numerous requirements that make sense for medicines but not for recreational products.  MHRA has yet to show how it can deal with the massively diverse range of products and suppliers without creating a violent restructuring of the industry, closing many SMEs and tending to commoditise the products into a few varieties made by big companies. It will destroy the consumer focussed rapid innovation model in the e-cigarette industry and slow down innovation – weakening the category relative to cigarettes.  It will create a DIY and black market that will present greater risks to users than medicines regulation would avoid.
6. Poor policy-making process. This regulatory regime has been assembled with only the most meagre consultation and stakeholder engagement.  In 2010, in the UK the MHRA consulted on whether the products should be classified as medicines and banned or continue unregulated (a false choice) and gave no alternative options or detail. In the EU, the Commission consulted on whether e-cigarettes should be included in the TPD, but without saying how they would be treated. There has been no consultation at all on the actual measures now adopted or anything close to them – even though this is an EU treaty requirement. Much of the TPD  violates principles of the treaties and has suspect legal base: scientific advice was ignored, impact assessment not done (EU) or done poorly (UK), anti-red tape machinery failed, and proper Westminster scrutiny was sidestepped. 6,000 words of e-cig regulation were created from scratch behind closed doors in the European Parliament and through a ‘trilogue‘ process. The directive is vulnerable to legal challenge both for the compatibility of the substantive measures with the treaties and for the process to create them.
7. What should happen? What is needed is a light touch regulatory framework that is designed for the products in question – not something different like medicines or tobacco.  This would comprise, for example:
a. Purity standards for liquids and flavours
b. Some operational standards for devices – electrical safety, what happens when liquid runs out etc
c. Sensible labelling conveying risks and benefits
d. Tamper proof containers for liquids – there is an ISO standard
e. Verification of consumer information – e.g. nicotine content
f. Marketing restrictions similar in concept to those used for alcohol – i.e. avoiding overt targeting of young people
e. Owners and operators of public spaces should decide whether to allow vaping – not the law
f. Flavours are integral to the value proposition and a high standard of evidence of harm or risk should be required before banning or restricting them
g. Better science and understanding is essential, but this is not a reason for paralysis
8. How could this happen?
a. European Union. Ideally policy change in the light of new evidence of the benefits of e-cigs should mean revising the TPD before it is implemented – this is politically highly unlikely to happen voluntarily, but may happen through legal challenge, at which point there is opportunity for a rethink. Failing that the government should seek the maximum flexibility and minimum restriction where there is remaining discretion – and start to insist that measures agreed are scientifically grounded, compatible with legal base and do actually comply with principles of proportionality, non-discrimination etc.
b. UK/England. MHRA should be encouraged to define a truly light touch regime or be clear to policy-makers that the the requirements of Medicines Act do not allow this. Much of the UK policy support proceeded on the basis that the MHRA can offer a light touch regime. An updated impact assessment would be a good idea. UK/England should be careful not to take measure that appear to protect children but are based on little more than opinion or assertion – the danger is that they will harm adult smokers for no gain. This is especially important where UK has discretion over flavours, marketing etc.
c. WHO – the WHO Framework Convention on Tobacco Control meets in Moscow on 13-18 October. Under no circumstances should the UK compound errors already made in the design of the EU directive by agreeing that e-cigarettes should be classified as ‘tobacco products’ under this convention.  They are not tobacco products and the measures used to control and suppress demand for tobacco are completely unsuitable for products that are an alternative to smoking and deliver a large health dividend when smokers switch. WHO needs a fundamental reappraisal of its approach to ‘harm reduction’ before it gets further involved in this area.
d. The e-cigarette industry and consumers. The industry is professionalising and better organised, and is capable of producing good proposals for self-regulation or idea to build into enforceable standards.  The government should apply some open-policy-making principles and start to take the firms involved more seriously and find out more about what consumers actually want.  In neither case do they want ‘no regulation’, but it is most definitely not what is on offer.
e. Science.  The Stop Smoking Services offer terrific possibilities for policy randomised controlled trials – for example comparing success rates in services where: (1) e-cigarettes are not offered or recommended; (2) where only only licensed medical products can be offered (i.e. the NICE guidance); (3) where the service offers a range of e-cig starter packs; (4) where a voucher is provided to spend in a vape shop.  This might be a good test of the government’s policy guidance.
f. Surveillance. The UK has one of the world leading systems for understanding what is happening in smoking and quitting smoking.  This system should be upgraded to take account of increasingly complex environment and behaviours created by the emergence of vaping – taking a more nuanced view of dual use, the way behaviour evolves as people learn to vape, reasons for relapse.  A way to use e-cigarettes industry money without conflicts of interest should be found to do this.

24 comments to Briefing: the case for e-cigarettes

  • susyn

    An understated issue is key philosophical differences between medical treatment and recreational use for the FDA. Zeller has pointed out numerous times that, “Nicotine is a drug” and as a drug, it can be used for replacement / harm reduction for individual treatment of a specific disease (nicotine addiction).

    I believe the problem lies with the FDA’s inability or unwillingness to approve ANY substance for “recreational use” that has the potential (real or not) to cause harm; this would include alcohol and caffeine if either of those products were to come under FDA oversight.

    Until the FDA finds another perspective, smokers will experience “abstinence or die” only from the FDA.

  • David Bareham

    Dear Bill
    Many thanks for your understandably impassioned and detailed response to my post on the Counterfactual website recently.Initially, just to let you know, I am a Respiratory Clinician: therefore, I am obviously very interested in any efficacious methods of smoking cessation. I can, will and do consult with patients on the issues around electronic cigarettes, and do confirm to them that, if all other more efficacious attempts have failed, that there is evidence that in a genuine attempt to quit, that utilising an electronic nicotine delivery device could be a route to successful cessation. I then suggest that they gain support in this attempt through the local Smoking Cessation Service, who, as per the latest Guidelines here, are “embracing” the electronic cigarette. (“Be open to electronic cigarette use in people keen to try them; especially in those that have tried, but not succeeded, in stopping smoking with the use of licensed stop smoking medicines”, NCSCT, May 2014). As per my response above, I accept that ENDS logically must be significantly safer than tobacco. However, we do still need to identify what risks they pose, and eliminate them (“Although some health risks from electronic cigarette use may yet emerge, these are likely to be, at worst, only a small fraction of the risks of smoking” (NCSCT). The first generation of cig-a-likes did not heat the fluids as high, and there is now evidence that there is more potential to produce carbonyl substances through heating the fluids involved to higher temperatures, via the thermal decomposition of solvents. This evidence does not automatically mean they are dangerous: we need more data to demonstrate that one way or the other. But, neither does it prove they are benign. Therefore, to pre-judge their safety profile now is premature.

    What I do know about the situation in the USA is thus:
    • The Kosmider et al paper that stimulated the FDA Commissioner’s response as stated also caused a Senatorial Hearing, where both the FDA and the CDC were called to account for their then current (May 2014) positions on Electronic Cigarettes.
    The correspondence contact for this paper is Maciej Goniewicz, who’s group in 2013 also published data in a paper entitled: “Levels of selected carcinogens and toxicants in vapour from electronic cigarettes” which concluded that:
    “Results We found that the e-cigarette vapours contained some toxic substances. The levels of the toxicants were 9–450 times lower than in cigarette smoke and were, in many cases, comparable with trace amounts found in the reference product.
    Conclusions Our findings are consistent with the idea that substituting tobacco cigarettes with e-cigarettes may substantially reduce exposure to selected tobacco-specific toxicants. E-cigarettes as a harm reduction strategy among smokers unwilling to quit, warrants further study.”
    This older paper is one very frequently quoted by strong advocates of the electronic cigarettes as being clear cut evidence that these devices are significantly safer than tobacco. I am convinced that they are, logically, a lot safer. But, the scientific fact remains that: in the second/third generation devices, when you heat these solvents to certain temperatures, they will produce carbonyls: carcinogens and toxins such as formaldehyde; acetaldehyde; acrolein, acetone. One of the group’s subsequent studies i.e. the Kosmider et al paper is the one that subsequently caused significantly more concern, and it is this one that we have been discussing, and it is the scientist’s conclusions that I am quoting: not politicians or public health bodies. Thus, on the Smoking and Tobacco Abstracts and News Bulletin for 3.5.14. states that: “Dr. Alan Shihadeh, project director, Virginia Commonwealth University, Center for the Study of Tobacco Products and associate professor, mechanical engineering, American University, Beirut: “If I was in a torture chamber and you said I had to puff on something, I’d choose an e-cigarette over a regular cigarette… But if you said I could choose an e-cigarette or clean air, I’d definitely choose clean air… And I definitely wouldn’t drip… Technology is way ahead of the science… We’re creating this stuff, and we don’t understand the implications.” (as attached)
    • You state that you and others have: “been urging government health agencies, NGO’s and academic researchers to conduct and fund important research and surveillance on e-cigs since 2007 with very little success . . . “ but then in the very next sentence refer to: “The growing mountain of scientific and empirical evidence . . .”. The two statements do appear to me to be at least a little incongruous and contradictory. It is my impression that ALL parties really acknowledge that there is just not enough data and new data coming out about the safety of these devices, the fluids in them and the vapours that they can produce when heated. This still begs the question of what the actual long term exposures may produce on humans i.e. all users, whether tobacco smokers or not.
    • The FDA actually currently state here:
    http://www.fda.gov/NewsEvents/PublicHealthFocus/ucm172906.htm

    that

    “E-cigarettes have not been fully studied, so consumers currently don’t know:
    • the potential risks of e-cigarettes when used as intended,
    • how much nicotine or other potentially harmful chemicals are being inhaled during use, or
    • whether there are any benefits associated with using these products.

    Additionally, it is not known whether e-cigarettes may lead young people to try other tobacco products, including conventional cigarettes, which are known to cause disease and lead to premature death”

    • I note your concern and frustration with what you interpret as the political pressures involved in this issue in the USA (“anti tobacco extremists and their left wing political allies”). I am certainly not qualified to comment on the politics in the USA, however, I am certainly happy to voice my own frustrations regarding the apparent influences that Big Tobacco have on our centre-right (Conservative Party) currently, and in the past, with: a former Philip Morris advisor, Lynton Crosby, currently paid as an Election Strategist by this Party ; apparently a previously paid BATCo employee recently being promoted to Exchequer Secretary to the Treasury (http://tobaccotactics.org/index.php/Priti_Patel); and, of course, the presence of Kenneth Clarke, a former executive at BATCo and Conservative Party Minister for Health (http://tobaccotactics.org/index.php/Kenneth_Clarke)

    • “anti tobacco extemists” . . . . . an interesting and challenging statement to say the least. When considering the following evidence:
    1) The motives behind the 1954 Tobacco Industry “Frank Statement” (http://tobaccotactics.org/index.php/Tobacco_Industry_Research_Committee)
    2) That Philip Morris knew about the cancerous nature of tobacco in 1961, as per this from the Legacy Tobacco Documents Library
    http://legacy.library.ucsf.edu/tid/kgp22d00
    3) Brown and Williamson knew about the addictive nature of nicotine in 1963:

    http://legacy.library.ucsf.edu/tid/xrc72d00

    4) What the evidenced philosophy of the Industry (or at least BATCo) states:

    http://legacy.library.ucsf.edu/tid/msu40a99

    5) The 7 CEOs of Big Tobacco’s Senatorial Testimony under oath in 1994, that they believed nicotine not be addictive, and one CEO even claiming that tobacco was no more harmful than “Twinkies”
    6) Their treatment of executive “whistleblower” Dr J.S. Wigand and family (the film, The Insider, was only on British T.V. this last week)

    7) The evidence regarding the Industry’s involvement in cigarette racketeering since the MSA
    8) The evidence involving their current involvement in unethical business in Uganda (http://tobaccotactics.org/index.php/British_American_Tobacco_Uganda_
    9) There really are countless other examples . . .
    10) I suggest, when I consider all the available evidence, that I logically and ethically become an “anti-tobacco extremist”. Considering all the evidence, it is surely indefensible to trust this Industry.
    • Unfortunately, I am not at all surprised by anything that Philip Morris do, as evidenced above, as they and others deliberately buried the evidence they had with regard to the harms of tobacco for decades. They predictably see electronic cigarettes as a challenge to their business, and will seek to distinguish or utilise that threat to their advantage. They sue to delay any form of legislation (e.g. plain packaging) or buy out any threat that may put a bridle on their practices. All of this was predictable, I would argue. The vast majority of the ENDS market in the UK since 2013 and especially since May 2014, is now owned by Big Tobacco http://www.tobaccotactics.org/index.php/E-cigarettes:_Marketing and there is already evidence that they are marketing to youth as in the past, for example, as per the Advert for Vype appearing on a children’s online game, October 2013, as per this link.

    • One last point on evidence: this pre-clinical abstract is certainly not evidence that electronic cigarette vapours cause lung cancer, but it is certainly not evidence that they do not. There have been many cell studies that have indicated that nicotine causes cancer, but to date we have no clinical studies to substantiate this. We do not yet scientifically and logically know if this will be the same with electronic cigarette vapours.
    Abstract B16: The effect of e-cigarette exposure on airway epithelial cell gene expression and transformation.
    1. Stacy J. Park1,
    2. Tonya C. Walser1,
    3. Catalina Perdomo2,
    4. Teresa Wang2,
    5. Paul C. Pagano1,
    6. Elvira L. Liclican1,
    7. Kostyantyn Krysan1,
    8. Jill E. Larsen3,
    9. John D. Minna3,
    10. Marc E. Lenburg2,
    11. Avrum Spira2, and
    12. Steven M. Dubinett1
    + Author Affiliations
    1. 1UCLA, Los Angeles, CA, 2Boston University, Boston, MA, 3Univ of Texas Southwestern Medical Center, Dallas, TX.
    Abstract
    Lung cancer is the leading cause of cancer-related mortality in the United States. Despite a strong correlation between cigarette smoking and the onset of lung cancer, the prevalence of smoking still remains high. Strategies to eliminate cigarette smoking have led to the emergence of new tobacco-related products as alternatives for cigarette smoking or tools for smoking cessation. The electronic cigarette (ECIG) is a battery-powered electronic nicotine delivery system (ENDS) designed to deliver nicotine without combusting tobacco. Since nicotine is widely considered the addictive component in tobacco with limited ability to initiate cancer, ECIGs have been advertised to be a safer alternative to tobacco cigarettes (TCIGs). However, the toxicity and potential carcinogenicity of ECIGs have not previously been evaluated. In this study, we assess the impact of ECIG exposure on the carcinogenic potential of immortalized human bronchial epithelial cells on a background of silenced p53 and activated KRAS (H3mut-P53/KRAS). This model is utilized because p53 and KRAS mutations are often observed in the airway of current and former smokers at risk for lung cancer. The epithelial cells were exposed to both a low and high concentration of nicotine in the ECIG vapor- or TCIG smoke-conditioned media. The lower nicotine concentration was selected to mimic the average plasma nicotine levels in ENDS users and did not demonstrate toxic or anti-proliferative effects on the cells. The higher concentration was chosen to represent the anticipated nicotine levels to which the epithelial cells of smokers are actually exposed. In anchorage independent growth assays, the in vitro correlate of malignant transformation, we found enhanced colony growth in the H3mut-P53/KRAS cells following a 10-day treatment with the high nicotine ECIG- and TCIG-conditioned media compared to the untreated and low nicotine treatment groups. We next assessed the effect of ECIG and TCIG exposure on cell invasion using a three-dimensional air-liquid interface (ALI) model. At baseline, H3mut-P53/KRAS cells exhibit invasive behavior in the ALI model, due to the downstream effects of P53 silencing and KRAS activation. Treatment of H3mut-P53/KRAS cells with low nicotine ECIG- and TCIG-conditioned media did not further enhance the degree of invasion observed in the untreated group. We will next examine the effects of high nicotine conditioned media on cell invasion. Finally, gene expression studies show 263 differentially expressed genes following in vitro exposure to ECIG-conditioned media for 96hrs. The high nicotine ECIG-conditioned media induced a gene expression pattern similar to TCIG- conditioned media and whole cigarette smoke exposure in the H3mut-P53/KRAS cells. Preliminary analyses indicate the observed ECIG-specific gene expression changes were concordantly changed following TCIG-conditioned media exposure. We will next compare the ECIG-induced gene expression signature to carcinogenicity-related gene signatures established in previous and ongoing clinical investigations and test ECIG-altered candidate genes for their ability to drive the malignant transformation of airway epithelial cells. These studies will determine the impact of ECIG exposure on lung carcinogenicity and provide needed scientific guidance to the FDA regarding the physiologic effects of ECIGs.
    Yours sincerely
    David Bareham

    • john

      David Thanks.

      The narrative about e-cigs seems to depend on view point (as do many conflicts about interpretation history) – looked at from the point of view of somebody who smoked for 30 years and who found not smoking very depressing, e-cigs are a good idea, looked at from the view point of a 18 year old who has never smoked e-cigs are perhaps not such a good idea. Unfortunately conflicts of ‘view point/ interpretation’ tend to be much more intractable and vicious than conflicts over facts(think of ‘climate change’ for a extreme example).

      In Australia smoking among those under twenty has become very rare-I travel a lot and have only seen two young smokers in the past 4 weeks. Find the idea that many non,tobacco, smoking 18 year old australians will become e-cig nicotine users a bit implausible.

      The only ‘non’ smoker that I know to be using e-cigs is a 58 year old pot smoker-( It apparently works better and is more economical).
      I gather from him that use of e-cigs for marihuana is growing like Topsy.

    • M Dolphin

      RE: The vast majority of the ENDS market in the UK since 2013 and especially since May 2014, is now owned by Big Tobacco

      A maximum of 25% is “the vast majority”? 50% of the current UK market is in second and third generation devices, and BigT only has about half of the remaining market (cig-a-likes). This gives a final figure of 25%, hardly a vast majority!

  • David Bareham

    Hi

    The response from Maciej Goniewicz, the correspondence contact for the Kosmider et al paper, on the A6 fluid is:

    “There are data in our paper on ingredients in fluid A6. Please see Table 1. It contained PEG. There is also a note under the Table 2, showing that this sample was different, since it contained PEG. Unfortunately, I don’t think we have any sample left as we used it for the study.”

    Moreover, as above, if it helps, re acrolein, the authors state:

    “in current study, we measured carbonyls only in two series of15 puffs, whereas in previous report, we used much larger samples (150 puffs). Thus, this inconsistency might be attributed to differences in detection limits. The other explanation would be that generation of acrolein increases with the duration of EC use. Extensive puff-by-puff analysis would facilitate verification of this hypothesis.”

    Does this help?

    David.

  • john

    David , William
    David
    The data sheet for the study actually gives what, on a closer look, seems to be two separate manufacturers for “A6” – in two very different countries- the Chinese manufacturer has been responsive and clear, the other, EC based manufacturer has not so far responded to my enquiries. A bit frustrating.

    However:
    •According to the study :Formaldehyde and acetaldehyde were found in 8 of 13 samples. Therefore formaldehyde and acetaldehyde were not found in 5 of the liquids tested.

    •Apart from A6 all of the liquids tested were, provably, based on VG and/or PG, and nicotine -dissolved in a solvent- is the solvent for pharmaceutical nicotine , a constant?

    •The results for A6 show only butanal detected : 104±96.

    •The results for the control VG/PG mix- C2 were: below quantifiable for m-Methylbenzaldehyde, and :222±85 for butanal.

    •On the other hand two of the worst performing liquids were also provably a VG/PG mix. However there is a problem : “A4” and “A5” are, according to the data sheet, the same liquid.

    •VG is stable to about 250C and PEG is stable to about 300C. The absence of detectable quantities of acrolein suggests that the temperature reached was provably well below about 250C, no ? On the other hand if PG is exposed to temperatures much above 130-150C, for a long enough time, it starts breaking down( into mainly lactic acid.)

    •Yet the results for the control PG liquid C3” were reasonably OK and are much better than the results for the other PG liquids tested. In fact the results for C3 are not that different to the results for C1,yes?

    Have a feeling that while it is quite plausible that A6 had some special quality; overall the results, at high energy levels, point more to the flavorings and other unknown/variable additives as the culprit.

    William

    PG ‘vapes’ at about 100C and VG (with %10 water) vapes at about 136C, at those temperatures non linear results are not likely. Any practical ideas as to how to stay at below about 140C?

  • David Bareham

    Hi William

    That is such a better explanation than i can give, that’s for sure! I am a Respiratory Clinician, not a physical scientist! I guess Dr Farsalinos could have gone into signifciantly more detail also. Thank you.

    Dave

    John: Just sending email now about fluid!

    Dave.

  • William

    ““The discussion about voltage is misleading and provides no useful information. Temperature depends on wattage, which is associated with both voltage and resistance! Thus, the discussion should be about watts only.”

    This is more correct than the original statement, but still imprecise. The temperature depends on multiple factors. Several are: wattage, configuration of the coil(s), airflow over/through coil(s), degree of wick saturation, degree of contact of wick with coil(s), ease of vaporizing the juice, surface area of the coil(s) coated with juice, how much of the coil is juice free, configuration of the vaporization chamber and heat radiated away without heating the juice and initial temperature of the juice. There are other factors, but these should suffice to show that analysis is NOT a simple matter.

    To illustrate how these factors can make a big difference – compare the heating element in a 750 watt electric oven to a 750 watt light bulb. They both use the same power (wattage) but the temperatures achieved are vastly different. The heating of the coil in the oven only produces a bright red color – while the filament in the lamp reaches a whitish color. The lamp coil is many times hotter than the oven coil. This difference is primarily due to the configurations of the coils and the surface areas of those coils.

    • Clive Bates

      Dear William – very helpful thanks for that…

      Instead of trying to control for thermal breakdown products by endless measurements of vapour under many permutations of operating conditions, wouldn’t it make more sense to specify a few operating parameters for devices – e.g. some sort of thermal control or what happens if it runs dry?

    • john

      William Hi
      have been having a look around , some of the next generation- the Mk4?- of batteries allow control of voltage and voltage and also offer a’Check atomizer/cartomizer resistance’ feature, could this be the way to go? (there are also devices made to simply check the resistance of any atomizer)

      • john

        Bugger :-)
        should read : “batteries allow control of voltage and Wattage and also offer a’Check atomizer/cartomizer resistance’ feature”

  • David Bareham

    Dear John

    Very interesting new tech option – many thanks. On face value at least, further harm reduction, if users will try and then utilise it? I will ask the correspendence researcher for the Kosmider et al paper about the liquid issue, and get back. The paper was published May 15th, but was reviewed in the six months previous. They should clearly still have those records, though, one supposes?

    Thank you.

    David.

    • John

      David re the liquid, it seems at least possible that a6 could be PEG should have a better idea by tomorrow.
      As for trying ultrasound or anything that fences out emergent results ,personally I would buy it.
      My first response to the study was concern about non linear effects and then obviously ‘where do you get A6’.

  • john

    Sorry to go on :-)
    My mate the chemical engineer has been OS. Intend to pick his brains about the study when he is ready.

    In particular I wonder if a different approach to making the vapor could be possible ? The power requirements for this approach do not look that onerous – http://www.piezoproducts.com/fileadmin/user_upload/pdf/jm_piezoproducts_funktionsweise_ultraschallzerstaeuber_en_02_03_2009.pdf
    No idea as to cost and durability.

    Not heating the liquid should cut out the room for nonlinear effects, no?

    • john

      Interestingly there seems to have been some breakthrough research in the area of small low power ultrasound vaporizers –

      http://www.worldscientific.com/doi/abs/10.1142/S233954781450006X?journalCode=technology

      We report here the technology and the underlying science of a new device for inhalation (pulmonary) drug delivery which is capable of fulfilling needs unmet by current commercial devices. The core of the new device is a centimeter-size clog-free silicon-based ultrasonic nozzle with multiple Fourier horns in resonance at megahertz (MHz) frequency. The dramatic resonance effect among the multiple horns and high growth rate of the MHz Faraday waves excited on a medicinal liquid layer together facilitate ejection of monodisperse droplets of desirable size range (2–5 μm) at low electrical drive power (<1.0 W). The small nozzle requiring low drive power has enabled realization of a pocket-size (8.6 × 5.6 × 1.5 cm3) ultrasonic nebulizer. A variety of common pulmonary drugs have been nebulized using the pocket-size unit with desirable aerosol sizes and output rate. These results clearly provide proof-of-principle for the new device and confirm its potential for commercialization."

  • john

    David
    On the subject of quality control- it is quite normal for manufacturers of things like over the counter pharma to be required to keep careful records of their inputs of certified grade ingredients that match their outputs of end products.

  • john

    David
    Do you know if the researchers kept the liquid ‘A6″? it would be good to get a analysis of what was in it (or perhaps more importantly what was ‘not’ in it). The spokesperson for manufacturer of the liquid (and they seems genuine and genuinely bemused by the questions) would like to see a pic of the label, is there one?

    Electrics is not my area but surely some sort of governor-‘fuse’ that cuts out when too much power flows is possible?

    Another possible factor in the mix is that apparently there is a very active community of Pot users that have been modifying/ramping up e-cigs so that they are powerful enough to heat marihuana leaf to the point that the THC is released.

  • john

    “An interesting finding of our study is that no toxic carbonyls were detected in a single sample with reduced content of VG and PG. In this product (A6), the primary solvent was polyethylene glycol (PEG). It would suggest that PEG-based e-liquids might have reduced toxicity from decomposition products.” This finding from the Kosmider et al paper has not escaped the attention of Dr Farsalinos, who has noted the potential significance of this finding, but sensibly he concludes that further studies need to be carried out.”

    There is no actual evidence that the liquid A6 contained any PEG at all. The manufacturer is clear that they do not use PEG . The study simply assumed that the lablel on the bottle was correct. In fact the results profile for A6 is not that dissimilar to the results for the PG/VG control liquid.

  • […] In response to my longer briefing, sometimes people say: well could you please state the case more concisely? So here is a shorter briefing, starting with a one paragraph summary… The case for a…  […]

  • Bill Godshall

    Another excellent post Clive, as was the longer version.

    In response to the lengthy post by David Bareham, it is critically important to see the forest through the trees, and to not let the tail wag the dog.

    All tobacco harm reduction advocates support more research on e-cigs, and some of us have been urging government health agencies, NGO’s and academic researchers to conduct and fund important research and surveillance on e-cigs since 2007 (with very little success, primarily because those same entities have been lobbying to ban e-cigs by intentionally misrepresenting the scientific and empirical evidence, and by repeating false and misleading fear mongering claims to confuse and scare the public.

    The growing mountain of scientific and empirical evidence indicates that e-cigs:
    – are 99% (+/-1%) less hazardous than cigarettes,
    – are consumed almost exclusively (i.e. >99%) by smokers and exsmokers who quit by switching to e-cigs,
    – have helped several million smokers quit and/or sharply reduce cigarette consumption,
    – have replaced more than 2 Billion packs of cigarettes in the past five years,
    – are as or more effective than FDA/MHRA approved nicotine gums, lozenges, patches and inhalers for smoking cessation and reducing cigarette consumption,
    – pose fewer risks than FDA/MHRA approved Verenicline (Chantix/Champix),
    – pose no risks to nonusers,
    – have never been found to create nicotine dependence in any nonsmoker,
    – have never been found to precede cigarette smoking in any daily smoker, and
    – have never been found to cause any disease.

    But in April 2009, Obama’s FDA revealed its unscientific, unethical and inhumane policy to deceive Americans about e-cigs and defend the FDA’s e-cig ban and nearly 1,000 product seizures by US Customs agents: “We don’t want the public to perceive them as a safer alternative to cigarettes.”
    http://www.webmd.com/smoking-cessation/features/ecigarettes-under-fire

    In July 2009, Obama appointee (and former Waxman staffer) FDA Deputy Commissioner Josh Sharfstein held a press conference (defending the agency’s unlawful and unwarranted e-cig ban from lawsuits by two companies whose products were seized) where FDA’s e-cig lab findings were misrepresented to scare the public to believe e-cigs are carcinogenic and toxic, where e-cig companies were falsely accused of target marketing to youth, and where it was alleged (without any evidence) that e-cigs are addicting children, can be gateways to cigarettes, can renormalize smoking, and don’t help smokers quit.
    http://www.fda.gov/NewsEvents/PublicHealthFocus/ucm173175.htm
    http://www.fda.gov/downloads/NewsEvents/Newsroom/MediaTranscripts/UCM173405.pdf

    Thankfully for the rule of law, public health, civil liberties, market competition and common sense, all 12 federal appeals court judges upheld Judge Richard Leon’s Janaury 15, 2010 ruling striking down FDA’s e-cig ban as unlawful.
    https://ecf.dcd.uscourts.gov/cgi-bin/show_public_doc?2009cv0771-54
    https://ecf.dcd.uscourts.gov/cgi-bin/show_public_doc?2009cv0771-55

    But since that court ruling, the FDA has never corrected or clarified any of the agency’s many false and misleading fear mongering claims about e-cigs, and instead has made many more false and misleading claims (as has the CDC, US SG and other DHHS agencies, Big Pharma financed health/medical groups, and their Democrat political allies) to lobby for FDA’s recently proposed e-cig regulations, which would (similar to UK MHRA):
    – protect cigarette markets from competition by e-cig products,
    – ban >99% of e-cigs and all tanks/e-liquid (the most effective for quitting smoking),
    – approve several ineffective cigalike products marketed by Big Tobacco, and
    – give the entire e-cig industry to Big Tobacco companies.

    At its Investor Day a month ago, Philip Morris International (which has been lobbying for FDA and UK MHRA regulations for e-cigs) stated that it was relying upon restrictive government regulations to turn PMI’s $2 Billion investment in new THR products (including hiring “300 world-class scientists and engineers”) into profits.
    http://investors.pmi.com/phoenix.zhtml?c=146476&p=irol-newsArticle&ID=1942860&highlight=
    http://www.media-server.com/m/s/get6yg4o/lan/en
    https://www.media-server.com/m/instances/8hjnb6wm/items/29n825fv/assets/75ngrwuk/0/file.pdf
    “Regulation is the second pillar supporting our RRPs business model.”
    “PMI has been seeking RRPs regulation because we see several benefits to rigorous regulatory standards for this new product category. Regulation provides assurance to regulators that RRPs claims are supported by rigorous scientific substantiation. Regulation gives consumers confidence that product information is reliable, and regulation establishes clarity in the marketplace for the industry.”

    While it is understandable that PMI and Altria (and recently BAT) would selfishly lobby for government regulations that ban >99% of e-cig companies (that cannot afford to comply with unwarranted regulatory burdens), it is absurd that Big Pharma front groups, anti tobacco extremists and their left wing political allies want to impose these same regulations that will make all tanks and e-liquid black market products.

    If/when that occurs, there won’t be any more research on tanks and e-liquid products, and their black marketeers will have no incentive to ensure their products pose no unnecessary or preventable risks.

    Unless/until government health agencies stop demonizing e-cigs, correct and clarify their many false claims, and change their prohibitionist policies on e-cigs, the entire discussion about (and research on) unknown or potential risks of different e-cig products (especially tanks and e-liquid) will be rendered useless.

    Bill Godshall
    Executive Director
    Smokefree Pennsylvania
    1926 Monongahela Avenue
    Pittsburgh, PA 15218
    412-351-5880
    [email protected]

  • David Bareham

    Hi Clive, John, Chris and Mark
    Very many thanks for all your responses previously to my post on 17.07.14. with regard to various papers. Apologies, firstly, for the delay in this response and, secondly, for misspelling Professor Hajek’s name in my post.
    • In fairness, Dr Farsalinos’ full response to the Kosmider et al paper is indeed very similar to the response he made to me with regard to it. However, what he clearly points out is that: due to the thermal decomposition of solvents, the higher the wattage, the more production of carbonyls e.g. formaldehyde we should expect to see. The experiment was carried out, perhaps on an inappropriate coil, at approximately 11 watts. He confirms that there are devices available that go up to 30 watts. He stated to me that:
    “The discussion about voltage is misleading and provides no useful information. Temperature depends on wattage, which is associated with both voltage and resistance! Thus, the discussion should be about watts only. There are devices going up to 30 watts now. I consider these extreme, but a lot of people use energy levels up to 10 watts. We have to realize that most successful users (in terms of smoking cessation) are not using cigarette-like e-cigarettes. They use at least 2nd generation (eGOs) and in most cases 3rd generation variable wattage devices. These are the future, because they provide the most pleasure as smoking substitutes. They may give to the user somewhat higher risk (maybe some more formaldehyde), but they are still much preferable compared to smoking.” (My emphasis). He continued:
    “Hello David,
    I don’t think that any of the studies till now are a reason for concern, in terms of the relative safety of e-cigarettes compared to tobacco. The coumarin issue is not deliberately introduced but is a contaminant for flavours. In this field there is the need for huge improvements. I have submitted a study to Nicotine and Tobacco Research (i hope it will be accepted and published soon) in which we assessed 159 e-liquids for the presence of diacetyl (an inhalation toxin, but approved for use in food). The results are quite worrying in terms of prevalence of this substance in the liquids tested, however, the levels were 100 times lower compared to cigarettes. Thus, there are many areas that need to be improved, but i think even now there is no doubt that e-cigarettes are significantly less harmful that tobacco. They sure can become even better though.”
    There appears no doubt in this scientist’s mind, therefore, that:
    1. Electronic cigarettes are significantly safer than tobacco, which I do agree with.
    2. There are greater exposures to carbonyls likely to found at higher temperatures (which he confirms currently to be in the range of 100-150oC in the most powerful devices).
    3. Are all users and potential users aware of this fact?
    4. I believe not. A Daily Mail headline report even yesterday with regard to a “new” piece of research by Professor Hajek et al (whose literature trawl ended in February this year, so inadvertently his team have missed some really interesting stuff) states that there are no carcinogens in these devices.
    5. I would strongly argue that all potential buyers of these, and any other products, have a protected right to know what the potential risks are. This was for decades not the case for smokers of tobacco.
    6. If we go with your upper estimate, Clive, of 5%, or Professor West’s recent upper estimate of 10%: what then is the predicted result if we compare electronic cigarettes with the catastrophic carnage inflicted by tobacco? Is it not incongruous to describe this as “negligible magnitude” as you have done, to the non-smoker of either e- or tobacco cigarettes, in a market where both are freely available to all? The market in the UK, especially since the publication of Professor West et al paper in May this year, is now predominantly controlled by tobacco manufacturers, as since the paper: Lorillard, JTI and PMI have all entered the e-cigarette market here. What is your opinion on the previous behaviour we have seen on how they market/ed cigarettes to children/adolescents? Do you believe their behaviour has changed, if you consider current behaviours, such as those seen in Africa and the Far East? Do you believe that they adhere to the same “harm reduction” theory that you do?
    7. I note that none of you commented on the Hutzler et al paper in your responses. This is interesting. With regard to this, Dr Farsalinos has stated to me:

    “For the study “Chemical hazards present in liquids and vapors of electronic cigarette” i was the reviewer assigned by Archives of Toxicology to assess this paper. I was also shocked to see the presence of ethylene glycol in many samples. It is a disgrace for these manufacturers to use this chemical, which is not supposed to be used for human consumption. For formaldehyde, i don;t think they found something new, in reality they overused the devices (used them until there is no vapor coming out). This is not the way a real user is using the e-cigarette.”
    8. Maciej Goniewicz, as the correspondence contact for the Kosmider et al paper, has stated to me that, with regard to a comparison between the findings of both the Kosmider et al paper and the Hutzler et al paper that:
    “I am very happy that the findings from our study were confirmed by other scientists. It looks like their finding are similar to what we reported previously. There are some chemicals in vapors, not only nicotine and nicotine solvents. It looks to me like carbonyl compounds (like formaldehyde, acetaldehyde, acrolein, aceton, etc.) are important toxicant in vapors. They found that levels of formaldehyde increased significantly when vapor was heated (to 150C). This is consistent with our report, where we found that increasing battery output voltage (which leads to increased vaporization temperature inside the device) led to higher levels of formaldehyde in vapor.

    Both studies pointed at importance of studying not only chemical composition of e-liquids but also generated vapor since some chemical can be generated during vaping. These chemical are inhaled by users and may exposed them to health risk. However, we need human subjects studies to look at long-term effects of inhaling these chemicals from e-cigarettes.”
    9. Dr Farsalinos notes that Kosmider et al found no acrolein. The researchers themselves comment on this as unexpected finding, and state on the paper:

    “in current study, we measured carbonyls only in two series of15 puffs, whereas in previous report, we used much larger samples (150 puffs). Thus, this inconsistency might be attributed to differences in detection limits. The other explanation would be that generation of acrolein increases with the duration of EC use. Extensive puff-by-puff analysis would facilitate verification of this hypothesis.”

    John: what I believe you are rightly getting at here is what Tianrong Cheng at the FDA has stated with regard to the chemical evaluation of electronic cigarette vapours:

    “Additional studies based on knowledge of e-cigarette user behaviours and scientifically validated aerosol generation and chemical analysis methods would be helpful in generating reliable measures of chemical quantities. This would allow comparisons of e-cigarette aerosol and traditional smoke constituent levels and would inform an evaluation of the toxicity potential of e-cigarettes.”

    Until this ideal becomes a reality, many of the current conclusions on both sides of this “debate” are, arguably, premature.

    10. Clive: you stated that: “A final point on this: it is not just the present of a harmful substance, but the exposure and the toxicity that matters. So we would have to assess how risky this exposure actually is, including how much time the user is likely to be exposed to the relatively high levels found under certain operating conditions.” This is erroneous: the other crucial determinant of potential harm here is HOW the substance is “consumed” by the user. This is an excellent description of what I mean:
    “Biodetoxification Systems: The Body vs. The Lungs

    Foods and cosmetics are “filtered” by the body’s detoxification systems, whereas the lungs lack any detoxification system. Therefore, a chemical may be “safe” if applied or ingested because the body’s detoxification systems disarm the potential harm that it may cause. But the very same chemical may be dangerous if inhaled through the lungs, since the lungs lack the capacity to disarm the potential of this chemical to do harm. The fact that the substances that appear on the GRAS list are designated to be used in foods and cosmetics/toiletries is important because ingredients that are ingested have a unique and different effect on the body than ingredients that are pyrolyzed and then inhaled. The biochemical digestion process of the approved additives has multiple opportunities to be detoxified in the body’s
    biochemical systems through biotransformation and biodetoxification. In the lungs, on the other hand, these same chemical reactions do not occur. This is because unlike the lungs, the body, through its biochemical systems, is able to distinguish different types of toxic substances based on their “functional groups” (i.e., the complex molecular structure that is characteristic of each chemical). For example, the body will metabolize a molecular structure known as an “aliphatic chain” more efficiently than it will metabolize a more complex structure known as an “aromatic ring.” This is because the former structure comprises a straight chain of saturated chemical bonds, whereas the latter structure is a cyclical chain of unsaturated chemical bonds. The lungs, however, not only lack the discriminatory capacity possessed by the body’s detoxification system, even worse, the lungs lack any capacity to identify the molecular structure of a toxic substance. Whereas the body has a variety of detoxification processes that correspond to the various molecular structures found in toxic substances, the lungs have none.” (May and Wigand, 2005).

    Thus, there is a significant amount of material surrounding the safety profile of PG/glycerol around the media all the time, and a significant amount concludes that, because PG for example is “GRAS” in foods, cometics, inhalers etc that it must be safe in e-cigarettes. This is clearly erroneous. PG utilised in my patient’s inhalers, for example, is not heated to 100-150oC prior to inhalation: the PG in the inhaler is not exposed to the risk of the consequences of the thermal decomposition of solvents. On this topic, Dr Farsalinos has stated to me:

    “I agree and i have repeatedly mentioned in my presentations and lectures that GRAS for food use does not mean that they are necessarily safe for inhalation.”

    Considering the above biology, this is a very important warning, that all users have a right to know about, when considering the potential effects of vapourisers.
    11. John: “An interesting finding of our study is that no toxic carbonyls were detected in a single sample with reduced content of VG and PG. In this product (A6), the primary solvent was polyethylene glycol (PEG). It would suggest that PEG-based e-liquids might have reduced toxicity from decomposition products.” This finding from the Kosmider et al paper has not escaped the attention of Dr Farsalinos, who has noted the potential significance of this finding, but sensibly he concludes that further studies need to be carried out.
    12. Clive: you state that:
    “We have to be careful not to be overprotective of children if it means we are careless with the health of adults for no real reason.”
    Dr Farsalinos has stated to me related to this issue that:
    “The ban on sales to youngsters (<18) is rational, however we should not forget a very important fact: most of smokers start smoking (and become addicted to it) before the age of 18. These people become the most addicted smokers in the future. Thus, banning sales at this age group will deprive us from a golden opportunity to reduce the nr of new smokers. However, i am not sure there is another way to control marketing of e-cigarettes in this age group.”
    This is logical and ethical, considering:
    1. The Industry’s Track Record on Marketing to youth for decades, and their continued behaviours
    2. The continuing uncertainties as to the exact potential harm posed by these devices: even if they do represent significantly reduced harm from tobacco, they may prove to the non-smoker in an “open market” far from benign, considering the physics and biology discussed above
    3. As much as adults DO love many flavours, as Lorillard have stated:
    "Kids may be particularly vulnerable to trying e-cigarettes due to an abundance of fun flavors such as cherry, vanilla, pina-colada and berry."
    4. As Professor Gilmore has stated:
    “If e-cigarettes are to work for public health by reducing smoking of tobacco, then they need to compete with cigarettes – impossible to achieve if the same companies are selling both products. Tobacco companies do not want e-cigarettes to cannibalise their existing cigarette market. Instead, they want dual use of cigarettes and e-cigarettes, which has no public health benefit.”

    5. Again, as Dr Farsalinos has stated to me:

    “I agree that dual use will not have the same benefits as complete smoking cessation, thus we should focus our efforts into convincing smokers to completely switch from tobacco to e-cigarette use.
    6. This is proving to be very difficult indeed, with high levels of dual use being observed in the cross-sectional population studies we currently have.

    NB. I note that Dr Farsalinos makes reference to the New York Times report on the Kosmider et al research. This is the official comment on this topic, by the Commissioner of the FDA. She is clearly taking the report very seriously:
    To the Editor:
    The emerging technology of electronic cigarettes poses important questions for public health officials. Much remains to be learned about the risks of e-cigarettes to health, as well as their possible benefits, particularly for those smokers who have not been able to quit using deadly conventional cigarettes. All of us in public health are concerned about any use of e-cigarettes by children and adolescents.
    “Some E-Cigarettes Deliver a Puff of Carcinogens” (“The New Smoke” series, front page, May 4) refers to the Food and Drug Administration’s recent proposed rule to extend the agency’s authority to include e-cigarettes. However, I’d like to clarify the assertion in the article that the F.D.A.’s focus is largely on what gets added to these products rather than the emissions in the product vapor.
    The proposed rule is a critical first step to bring an end to the completely unregulated e-cigarette marketplace. When it is finalized, e-cigarette companies will be required to report the levels of harmful and potentially harmful chemicals or chemical compounds delivered by their products. But we cannot enact a rule on reporting or restricting e-cigarette emissions until this foundational rule-making is completed, which is one of our highest priorities.
    The F.D.A. is committed to the science-based regulation of these products to better protect public health. Where the science does not exist, we are able to finance the research to answer key questions related to e-cigarette safety and consumer behavior, including four studies that will focus on the contents of e-cigarette vapor.
    MARGARET A. HAMBURG
    Commissioner
    Food and Drug Administration
    Silver Spring, Md., May 6, 2014

    • As a user I can directly answer at least one of your questions.

      First of all, we don’t really need to know the physical and chemical details. Applying too much power to a vaporizer results in a phenomenon called “dry puff” or “dry hit”. This is a very harsh, unpleasent taste. Worse than tobacco smoke. Even an inexperienced user will notice it and stop vaping.

      at what power the atomizer works best (“sweet spot”) depends largly on the design of the coils(s), wicking, and airflow.

      Vaporizing is a dynamic process. When you apply to much power, the liquid flow is to slow and the coil starts to run dry. Then the cooling effects of the flowing liquid itself and the evaporation process are increasingly diminished and the tmperature at the coil quickly rises out of the optimal operating range.

      When you apply insufficient power for the design, there continuously is too much liquid at the coil, preventing it to reach the optimum temperature. Then insufficent vapor is produced.

      Most of the mass produced atomizers are designed to operate best at 3.7V (nominal voltage of an unregulated standard battery) or at 3.3V (contant voltage by simple control circuit). They simply can’t handle the required liquid flow if you apply more than 4.2V (maximum of a lithium battery). Standard batteries are also limited to the current they produce and simply stop operating when the drain is too high.

      In contrast, an atomizer designed to handle more power will require either a higher voltage or a more current (low resistance). It won’t work satisfactory with standard batteries, if at all.

      Of course, more power means more vapor. But only if the atomizer is designed to deliver it.

      One basically erroneous assumption in the referenced study is, that vapers simply increase the voltage to get more nicotine.

      The voltage/power contraol of these controllable batteries is used to find the “sweet spot” of the atomizer, Where it operates best. the possible voltage boost is used only with high performance atomziers that require it to operate best.

      And contrary to the assumption, these high performance atomizers aren’t used to deliver more nicotine. Most people who use them drastically reduce the nitotine content of their liquids, because too much nicotine simply is unpleasent.

      When you want more nicotine you simply use stronger liquids or puff more often. Users who like to puff a lot are also known to reduce the nicotine content of their liquids.

      It would be quite simple to ask people who know the basics instead of just making unfounded assumptions and drawing invalid conclusions from valid data.

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