E-cigarettes 95% less dangerous? Myth, scientific lies, and manipulations| Tabaccologia

A tenacious myth maintains that electronic cigarettes (ENDS) are 95% less dangerous than traditional cigarettes. This myth stems from the publication of an article dating back to 2014. Subsequently, various public health organizations, including some very prestigious ones, have referred to this publication without verifying it. Still others then relayed this information (to clarify: they quoted articles that themselves quoted other articles and so on) without ever making the effort to trace its source. This myth is actually based on an erroneous and heavily biased interpretation of the opinions of a small group of people, many of whom had confirmed ties to the tobacco industry. What’s more, it has no sound scientific basis. Indeed, current data do not allow one to draw such precise conclusions on the relative risks of ENDS compared to traditional cigarettes. In addition, a majority of the criteria taken into consideration in the 2014 estimate are not related to health, whereas subsequently the figure of 95% has essentially been applied to the health hazard of the products. Despite numerous attempts to expose and dismantle this “95% myth”, this misinformation continues to circulate and the tobacco industry shamelessly exploits it (Figure 1). We are committed to shedding light here on the origin and consequences of this manipulation that is harmful to public health.

Origin of the “95% myth”

At the root of this myth is a 2014 publication that aimed to assess the relative risk associated with various nicotine-containing products. This publication highlights the results of a meeting organised in 2013, which were in reality only a series of subjective estimations by a self-appointed group of 12 experts. Several of these experts had financial links or interests with the tobacco industry [1].

The group of experts was brought together in London for a facilitated workshop in July 2013, at the instigation of the Independent Scientific Committee on Drugs [an English NGO now called DrugScience). This committee comprised “selected” experts from different countries to supposedly guarantee a diversity of viewpoints and perspectives, diversity that would therefore be “self-evident”. However, no details were provided regarding the selection criteria or the skills required. It even appears that some participants had no expertise in the field of tobacco, such as Kgosi Letpale, a South African ophthalmologist who appears to have never conducted tobacco research. Nor does he appear to have been active in this field, either before or after the London meeting; he seems to have been chosen solely on the basis of personal connections.

Furthermore, concerning the recruitment of experts, the authors specify: “There was no formal criterion for the recruitment of the experts…”. In simpler terms, this could be paraphrased as follows: “I gathered a group of friends”. Despite these significant limitations, the article was published and subsequently taken seriously.

The Independent Scientific Committee on Drugs was founded by David Nutt in 2010 [2]. Nutt is a British professor of neuropsychopharmacology whose views on the use and risks associated with certain substances are controversial. He had previously chaired the Advisory Council on the Misuse of Drugs (ACMD) from 2008, but was removed from that position by the UK government because of his views on the use and risks of cannabis, which he considers as presenting a relatively low risk of psychotic illness, and his outspoken opposition to public policies on this subject [3].

A highly questionable method

The method adopted for this study was that of a multi-criteria decision analysis (MCDA). In the case of this publication, the 12 experts themselves chose the products to be evaluated, defined the risk criteria (14 very disparate criteria of danger or harm), and ranked the products according to these criteria. Among the criteria we find a majority that are not health-related (e.g. loss of material goods, loss of relationships, injury and accidents; crimes, environmental damage, family adversities, international damages, economic costs, community impacts).

With regard to the criterion of product-related crime, we should note that in 2014 the black market for ENDS was still insignificant, whereas the black market for cigarettes had existed for a long time in many countries (often fueled by the large tobacco companies themselves). The same applies to the environmental impact criterion. In 2014, the negative impact of cigarettes was already enormous, but that of ENDS almost negligible. Today the impact of ENDS, and in particular disposable ENDS, has become a major ecological disaster [4], which alone should be enough to justify banning these products.

For the criterion of dependency, Nutt doesn’t hesitate to put forward, without much basis or critical discussion, assertions that are at least questionable, if not downright irresponsible. “There is also some evidence that cigarettes are the most dependence-forming product and products with less harm also may be less dependence-forming”, based on a single article that now appears completely outdated [5]. The evolution of electronic cigarettes, the power of their batteries, and the forms and quantities of nicotine they are able to deliver have changed a lot since the first products appeared on the market more than 10 years ago [6]. Today, it’s evident that the nicotine delivered by ENDS is just as addictive, if not even more so, than conventional cigarettes [7].

Thus, on the assumption that cigarettes present a 100% risk, the experts concluded that water pipes (shishas) presented a 14% risk and ENDS only a 4% risk. Based on these figures, it would therefore be necessary to say that ENDS would, according to these experts, be 96% less dangerous than cigarettes, and not 95% as was finally reported later.

However, MCDA oversimplifies complex real-world scenarios, bases its reasoning on subjective assumptions, and ignores interdependencies among criteria. It is important to critically assess the limitations of MCDA and to recognize that results are derived solely from qualitative factors and the opinions of participants. The use of MCDA, in particular in Health Technology Assessments (HTA), has also been widely criticized [8].

The article itself mentions certain limitations. The authors recognized in particular that they lacked tangible evidence concerning the dangers of most of the products according to the majority of the criteria used (“lack of hard evidence for the harms of most products on most of the criteria”).

Who is hiding behind this article?

At the end of the article, the authors thank EuroSwiss Health (Switzerland) for its funding and the LIAF (Lega Italiana Anti Fumo) for its support, without specifying what “support” is in question.

EuroSwiss Health is in fact a single person, Delon Human, a South African doctor living near Geneva. He has a long history as a consultant entirely paid by the tobacco industry [9]. Human regularly creates new “organisations” of which he seems to be the sole manager and collaborator. EuroSwiss Health was founded in 2003, never had a website, and apart from funding this 2013 research, never seems to have had any other activity. We then also find Delon Human as co-founder in 2015 of the African Harm Reduction Alliance, with the South African ophthalmologist Kgosi Letpale. Apart from lending his name and image, the latter does not seem to have any expertise in the field of smoking. The most recent of Human’s creations appears to be Health Diplomats [10], apparently launched in 2020, which is nothing more than a website in which industry-funded reports have been published to support the tobacco industry’s vision of harm reduction, and thus promote alternative products [11].

The Lega Italiana Anti Fumo (LIAF) is an NGO founded in 2003 by Riccardo Polosa, another of the authors of this article. Mr. Polosa is a doctor from Catania in Sicily, whose direct and indirect links with the tobacco industry have been amply demonstrated. Mr. Polosa has received funding from the tobacco industry on several occasions, as for example from Philip Morris International, or from the Foundation for a Smoke-Free World an organisation itself founded by PMI [12]. We also find links between Human and Polosa in 2019, because since then Polosa has been a member of the Medical and Scientific Advisory Board (MSAB), headed by Human, of PharmaCielo, a Canadian company that produces and sells cannabis products [13].

EuroSwiss Health seems to be rather an empty shell, and LIAF an NGO with no real resources of its own, but with definite links to the tobacco industry; it therefore seems to us legitimate to question the real source of funding for the London meeting.

Public Health England’s adoption of “95%” and the birth of the myth

The first to cite Nutt’s article was Public Health England (PHE) (England’s former national public health agency) in a 2015 report [14]. But PHE in 2015 went even further than simply repeating the argument, making it the focal point of a press release at that time by putting it directly in the headline [15]. This form of communication certainly contributed a great deal to the propagation of the “95% myth”, as Professor Glantz pointed out in his 2015 commentary, which also heavily criticized Nutt’s article [16].

The PHE report, from its introductory page, chose to give a lot of prominence to the “95%”: “In a nutshell, best estimates show ENDS are 95% less harmful to your health than normal cigarettes […]” [14]. It is important to focus on the language chosen: why underline so markedly in the introduction to this report the ‘value of 95%, based on the best estimates?’ In 2015, Nutt’s article was not the ‘best estimate,’ but the only published estimate. This was not a sufficient reason to consider it valid or good.

Further on, among its eight key messages, the report again highlighted this figure: “There has been an overall shift towards the inaccurate perception of EC [electronic cigarettes] being as harmful as cigarettes over the last year in contrast to the current expert estimate that using EC is around 95% safer than smoking” [14].

In the body of the report, we find mention of the “95%” figure: “It had previously been estimated that EC are around 95% safer than smoking. This appears to remain a reasonable estimate” [14]. To substantiate this claim, the English report cites Nutt’s article as well as an article by Polosa, who in turn states that ENDS are less risky but only cites Nutt’s article. At no point does the English report take a critical look or even attempt to examine the foundations of Nutt’s article.

Finally, the report concludes that it is necessary “to publicise the current best estimate that using EC is around 95% safer than smoking” among its “policy implications”.

On the basis of an article with particularly dubious methodologies, thus having no scientific validity, and without any critical discussion, PHE gave free credibility to a figure that is now easy to communicate, then undertook to disseminate it proactively. The “95% myth” was well and truly born.

Immediately, tobacco and nicotine companies rushed to take up and exploit this figure in their communications. We thus find on many pages of websites selling electronic cigarettes very prominent mention of the “95%” figure.

Despite the many criticisms [17], the English public health agency has continued to support and propagate the “95% myth” [18] without providing more solid scientific evidence and even admitting that it is a “good” way of communicating [19]. An admission which, in our view, amounts to a tacit confession of misuse (Figure 2).

Prior to its dissolution in 2021 and the transfer of its functions to other agencies, the independence of PHE had been in question. Doctors had criticized the organisation responsible for health protection for its work with a vaping lobby group that is itself linked to the world’s largest multinational tobacco company [20]. These links cast a troublesome shadow over PHE’s positions regarding the use of electronic cigarettes.

In England, the “95% myth” has been fully embraced by ASH UK, while other organisations, including ASH Scotland, oppose it. ASH UK in no way represents all tobacco control organisations in the UK. Even today, the ASH UK website promotes the “95% myth” [21].

In Switzerland too, unfortunately, public health experts and organisations have taken up the “95% myth” and continue to spread it today, even claiming that there is “expert consensus” [22]. This to the delight of the tobacco industry lobby, which opposes any increase in taxes on cigarettes or any other product. A UDC member of the National Council, for example, recently argued against taxing ENDS, saying: “The health risk of e-cigarettes is 95% lower than that of traditional cigarettes,” and that “We should take this into account to set taxation, i.e. 11 centimes per milliliters instead of 20”. A tax of 20 centimes is insufficient, but this elected official would have liked to reduce it by half [23]. Like many other parliamentarians, the elected official had received a document produced by a public health organisation that continues to peddle the “95% myth” with no discernment and without realising that they have fallen into the tobacco industry’s trap.

Naturally, the Swiss Vape Trade Association (SVTA), which represents traders and manufacturers of ENDS, liquids, and accessories, has enthusiastically taken up this myth and invokes it at every turn (Figure 3). The “95%” is omnipresent both on the website of this association, which never cites the original sources, and in its statements opposing ENDS taxation [24].

Criticism of the Nutt study

In August 2015, a week after the publication of the PHE report, The Lancet published an editorial entitled “E-cigarettes: Public Health England’s Evidence-based Confusion”, denouncing Nutt’s publication and demonstrating that the claim of “95%” taken up by the PHE had no scientific basis and was totally arbitrary. The Lancet also denounced the fact that the majority of the authors of this publication had obvious links with the tobacco industry [25]. The Lancet’s criticisms were quickly taken up by the English press, notably in The Guardian, which also highlighted the conflicts of interest of the authors of the article and the methodological weaknesses [26]. Immediately after The Lancet, another prestigious scientific journal, the British Medical Journal (BMJ), also criticized Nutt’s pseudo-study [27].

On 19 March 2016, The Lancet agreed to publish a letter from Nutt and his co-authors in response to its editorial [28]. This letter did not provide valid arguments to counter The Lancet’s criticisms. The letter went so far as to claim that the paucity of evidence of serious harm to ENDS users since they were first marketed in 2006, with millions sold, was proof in itself [28]. We are here obliged to recall the aphorism, often attributed to astrophysicists Martin Rees or Carl Sagan, that “absence of evidence is not evidence of absence”.

Since then, faced with the spread of the “95% myth” and its exploitation by the industry, many other voices have regularly risen to denounce this figure as manipulation.

Some criticisms have also focused on the fact that it is not possible to establish relative risks. Comparative safety predictions not based on fact, such as the quantification of ‘95% less dangerous,’ are not useful for estimating the risk of ENDS and should not be used when discussing or promoting ENDS [29].

Subsequent scientific panels convened by other governments have directly and indirectly rejected Public Health England’s position. Neither the Nutt article nor the Public Health England conclusions were referenced in the 775-page report prepared for the FDA by the National Academies of Science, Engineering, and Medicine [30], although the 5% relative harm estimate was identified as supported by many scientists (p. 634). The 122-page report of the European Commission’s Scientific Committee on Health, Environmental, and Emerging Risks (SCHEER) [31], published in 2021, also made no reference to either Nutt or PHE. A report commissioned by the Spanish government and first published in 2020 concluded that “the claim that the risk of e-cigarette use is reduced by 95% compared to traditional cigarettes is not supported by current evidence” [32].

In February 2020, an article published in the American Journal of Public Health returned to the question by qualifying the “95% myth” as a factoid, i.e. unreliable information repeated so often that it ends up being accepted as a true fact. If this factoid was unreliable and lacking in foundation in 2013, it is certainly even less reliable today, given the emergence in recent years of conclusive evidence documenting the substantial harms associated with ENDS use. What’s more, the electronic cigarettes available today are vastly different from those available in 2013. It would be irresponsible to claim that the devices currently on the market are safer than tobacco cigarettes [33]. These criticisms have been echoed by other strong public health institutions [34].

Philip Morris continues to manipulate the evidence and play with numbers

The tobacco industry, with its long tradition of scientific manipulation and lies (it denied until the 1990s that cigarettes were addictive) [35], couldn’t miss such a great opportunity to fund studies aimed at exploiting this myth in order to promote themselves and sell more products.

A recent pseudo-study repeats the relative risk approach of Nutt’s 2014 article, which has benefited the industry so well [36]. Employees of Biochromex [37], which presents itself on its site as a company that provides “life science expertise and strategic consulting services to the pharmaceutical, healthcare, and consumer goods sectors”, have signed off on a supposedly systematic literature review. Based on Nutt’s highly controversial article, they have developed a new, equally questionable scale of relative product risks (Figure 4). According to this scale, ENDS would only present a risk of 2.7%, and heated tobacco products (HTPs) – such as PMI’s IQOS – only 4.5%. We won’t dwell here on the numerous methodological weaknesses of this new “study”.

This article appeared on the online platform F1000, which claims to offer a transparent peer-review process guaranteeing the scientific quality of its publications. However, this platform seems to be easily manipulated. The article by Biochromex (which, it must be emphasised, is a consulting firm) is funded by the Foundation for a Smoke-Free World (founded entirely and solely by PMI), but the exact amount of this funding is not mentioned anywhere [38]. This is not the only funding from the PMI foundation to Biochromex. Despite its highly scientific language, this publication raises many questions, both about methodology and independence.

Reading the peer reviews of this article is fascinating and even stunning. One of the two reviews is conducted by none other than David Nutt himself. The latter, unsurprisingly, approves the article with a comment unrelated to the scientific method of peer review. On the other hand, he takes great care to denounce the “powerful anti-vaping lobby” [39]. The second positive evaluation is even more surprising, because it is signed by four employees of Altria, PMI’s parent company [40]. Representatives of the same industry that commissioned the publication are therefore the ones who evaluate and approve it. What a magnificent example of scientific independence.

Looking at PMI’s advertising and marketing of its IQOS product, the company’s interests become apparent. According to PMI, IQOS are also 95% less toxic than traditional cigarettes (Figure 5). The “95% myth” works perfectly well in communication and is easily understood even by a general audience. Naturally, ultra-liberal political circles defending the interests of the tobacco industry and advertisers argue that such advertising is necessary to “properly inform” consumers.

Conclusion: the “95% myth” is nothing more than a manipulation and a lie used by the tobacco industry

Today’s ENDS are highly differentiated and heterogeneous products. We find a wide variety of products: open or closed systems, and multi-use or single-use and disposable ENDS. Batteries have become much more powerful. Liquids contain nicotine salts and a huge variety of chemical substances (flavours and additives). What’s more, most of these devices and the chemical liquids they contain are produced in China, and are not subject to any health controls, quality standards, or guarantees. It is therefore impossible to speak of a single or uniform product. Most experts agree that ENDS generally contain fewer harmful chemicals than traditional cigarettes. However, no one is able to go beyond this very general assumption and the consumer of these products can never be sure of what they actually contain.

The real question is to what extent electronic cigarettes are dangerous for health. It is essential here to remember that any substance containing nicotine can be dangerous to health if its distribution is not controlled by health professionals, as is the case with nicotine substitutes used in withdrawal and approved by a medical authority. The dangers are particularly great when inhaled with other chemical substances. Recent research shows that ENDS present significant respiratory and cardiovascular health risks. We do not yet have the necessary hindsight to assess the long-term risks.

Continuing to repeat that ENDS are 95% less dangerous (or “safer”) than cigarettes is false. Basing public health positions on this assertion today, knowing full well how this figure was invented, is irresponsible and either aligns with the scientific lies propagated by the tobacco industry, or is a mix of naivety, incompetence, and/or vested interests.

In the age of digital information and social media, false information and the most absurd claims can circulate rapidly and reach millions of people, misleading even the most attentive. Among the most worrying types of misinformation is pseudo-true or false but plausible scientific information. The “95% myth” is a striking example that illustrates how powerful economic interests exploit public ignorance and gullibility to make profits.

A scientifically based debate on the risks and possible benefits of ENDS is needed

While in general it is admissible to affirm that the liquids of electronic cigarettes contain fewer toxic substances than the tobacco used in smoked or heated products, it’s not possible to scientifically quantify how much lower the risk of consuming these products is. A debate is needed on the relative danger of ENDS and the potential for risk compared to other forms of tobacco and nicotine consumption. But this debate must imperatively avoid oversimplifications – useful only for communication and the interests of certain parties – and must take place within a serious scientific framework, totally independent of powerful commercial and financial interests marketing these products.

It’s essential to understand that when it comes to communicating the risks of ENDS, it is not enough to simply describe the problem. We must develop measures that ensure that public health is not further compromised, especially among young people. As public health professionals, we need to communicate that we are aware that there is still a knowledge gap. Not only do we lack up-to-date surveillance and usage data on new products, especially in Switzerland, but because the market for new products is evolving so rapidly, conducting longitudinal clinical studies on these products is difficult. The heterogeneity of the products being placed constantly on the market is in itself a sufficient argument to show that it’s not possible to put a figure on even the least of the dangers of these products.

To overcome this problem, some authors suggest that we now focus on high-level scientific evidence concerning ENDS-associated toxicity, nicotine addiction, asthma, and specific ENDS-related damage (explosion, poisoning). An important target group for communicating these ENDS risks are those using several tobacco and nicotine products (dual or multiple use) [41]. A growing body of evidence suggests that, compared to the exclusive use of tobacco cigarettes, dual use carries additional rather than reduced risks, particularly among high-risk populations (children, pregnant women, et al).

To preserve the credibility of public health experts, it is essential to convey evidence transparently, without establishing causation based solely on association. Particular attention should be paid to the communication of accurate statements. In addition, avoiding direct comparison between the harms of traditional cigarettes and ENDS is recommended due to existing uncertainties, in particular those related to the high prevalence of dual or multiple product use, the variability of types/generations of ENDS and in their levels of nicotine content, and to a lack of rigorous and standardised comparative studies.

Figures and tables

Figure 1.Even sites selling disposable electronic cigarettes recently put forth the “95% myth” to promote their product (consulted on 15 August 2023).

Figure 2.Exploitation of the “95%” figure by websites selling electronic cigarettes.

Figure 3.Swiss Vape Trade Association page (consulted on 16 August 2023).

Figure 4.Relative risk scale according to Murkett et al. [36].

Figure 5.Various examples of advertising for IQOS exploiting the “95% myth”.

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