Polosa on Metals in E Cigarettes

Metals In ECigarette Vapour: Do You Need to Worry?

Are you worried about metals in ecigarettes? With recent media headlines screaming that ecig vapour contain metals, you won’t be the only one.

But with the levels of metal seemingly very low, I thought further analysis was needed. That proved difficult, as every study into metals in vapour and cigarette smoke seems to use different variables.

Fortunately, in the latest of our Interviews with the Experts series, Riccardo Polosa, a world expert in tobacco addiction and respiratory medicine who has also carried out research into electronic cigarettes, has kindly agreed to answer our questions on metals in ecigs, as well as other concerns vapers have.


Metals in ECigarette Vapour

vapers polluted citiesJD: Recent studies have found increased levels of chromium and nickel in ecigarette vapour. Other metals such as lead and zinc were also found but at lower levels than conventional cigarettes. How concerned should vapers be about these levels?

RP: They should not. Current findings indicate that e-cigarettes are by far less harmful than tobacco cigarettes. First, levels of metals found in these studies are well below the maximum permissible daily exposure from inhalational medications according to the US Pharmacopeia.

Second, although the levels found in e-cigarettes may pose some residual risk, it is by far lower compared to tobacco cigarettes. Please keep in mind that cigarette smoke contains a cocktail of more than 7000 toxic chemicals with more than 40 recognized carcinogenic substances and focusing on trace levels of metals does not create significant health advantage, but only alarmistic headlines.

Third, considering the reports from the environmental protection agencies, vapers should be more concerned of the air they breathe in polluted cities rather than their vaping!

Finally, product innovation (new materials, cotton wicks, etc) will eventually minimize these residual risks.

Vapers should be more concerned about polluted cities than vaping – Prof. Polosa

JD: The levels of metals found in ecigarettes fall well below the US pharacopeia maximum permissable daily exposure of heavy metals from inhalation medications – for example the USP maximum permissable daily exposure to lead is 5 micrograms, whereas the ecigarette only emits 0.09616 micrograms an hour (and that is when it is continuously used). If this is so, why has there been so much concern? 

RP: Portraying trace levels of a certain chemical as harmful is a common tactic used by journalists, lobbyist groups, and even governments to incite chemophobia to the public, which is now fuelling much of the emotional debate over ecigs. Of course, simply associating hazard with the presence of a metal does not mean that this in itself is dangerous.

It is the dose that makes the poison, and so by that understanding, everything can be toxic at some level. But everything we touch, see, and smell is made up of chemicals, and anything reduced to its chemical name can sound sinister when presented to people who are unfamiliar with chemistry.

Many journalists and lobbyist groups exploit this ignorance to their advantage when they want to demonize something and perpetuate ignorance.

Readers of this blog will be all too familiar with this tactic, in the example of propylene glycol. Any article that wants to portray e-cigarettes as negative manages to neatly fit in a statement about propylene glycol being an ingredient in antifreeze.

Of course, just because propylene glycol (or any other chemical) may have anti-freezing properties does not make it dangerous, and considering how ubiquitous propylene glycol is, fears regarding it are mostly unfounded. It is safely used in theatrical fog and asthma inhalers and many other common consumer products (like lotions and toothpaste).

JD: Does this mean there could be higher levels of metals in medications?

RC: Metals in low concentrations can be used as preservatives and bactericidal in medicinals, but I do not have comparative data to comment on.

JD: Are the metals present in secondhand vapour a health threat to bystanders? 

RP: Secondhand smoke is known to contain thousands of chemicals and can cause health damage. Using an e-cigarette in indoor environments may involuntarily expose bystanders to trace levels of nicotine, but not to toxic tobacco-specific combustion products. Full stop.

JD: ROHS regulations require that hardware and cartomisers are tested for lead. How is it possible that lead, thought to originate from hardware, was present in the vapour? (I have also heard that rumours that poor quality cartomisers were used in one study – is this true?)

RP: Trace levels of lead have been found in some EC vapours, but similar amounts were also detected from the Nicorette inhalator in the same study. The source of lead in vapour can be the stainless steel in the coil made with the much cheaper ferritic stainless steels that contains lower chromium and nickel content, but can contain lead.

Clearly, correct customer information, implementation of safety and quality standards and product innovation will eventually eliminate these residual risks.

In future, specific research funding must be devoted to this objective.

Ecigarettes and Pneumonia

E Cigarettes pneumoniaJD: Following on from media coverage, some people believe ecigarettes can cause pneumonia and other lung problems. How serious is this threat?

RP: There is no such threat!

Exogenous lipoid pneumonia is a rare condition that may occur from excessive or inappropriate aspiration or inhalation of fatlike material contained in commercial products such as oil-based laxatives, lip balm and flavoured lip gloss.

In the face of millions of vapers worldwide, electronic cigarette use has been linked to lipoid pneumonia in only two cases, one in the US and the other one in Spain. After careful review of their clinical notes, I came to the conclusion that the link of electronic cigarette use to lipoid pneumonia is pure speculation:

1) there is no way that regular exposure to glycerine in e-vapour will cause accumulation of fatlike material in the lung, because glycerine is NOT a lipid but an alcohol;

2) in the Spanish case, radiological evidence for lipoid pneumonia was preceding electronic cigarette use, hence it is was not a consequence of vaping;

3) in both cases I could identify a more plausible cause for these patients’ lipoid pneumonia.

Nonetheless, I am aware of some users intentionally mixing up vegetable oils in their e-liquids, but I would recommend against this practice.

The link of electronic cigarette use to lipoid pneumonia is pure speculation – Prof. Polosa

The Media and Ecigs

E Cigarettes effect on asthmaJD. Vapers insist their health has improved since switching and some studies have shown a reduction in asthmatic symptoms. Doesn’t this seem to contradict what is currently being publicised on the media?

RP: We have recently shown that asthmatic smokers who switched to regular e-cig use experience objective and subjective improvements in asthma outcomes. This is a positive development for asthmatic patients who do not intend or cannot quit smoking and similar benefits are now being proven in patients with significant cardiovascular risks.

Unfortunately, creating alarmistic headlines around the electronic cigarette is more fashionable than praising their beneficial health effects. I think that the media, organs par excellence of the correct information, should judiciously fulfill their mission, that is to inform and not simply create a scoop. I fear I am just daydreaming.

Flavourings and Colours Used in Eliquid

Food colouring in e cigarettesJD: There is seems to be confusion on the effect of flavours when inhaled, could you clarify the concerns? Ecigarettedirect and other ECITA members restrain from adding food colouring to their eliquids, however other manufacturers have been known to do so. Is the use of food colouring a concern?

RP: Whilst flavours are clearly an essential element of e-liquids in order for e-cigarettes to be an attractive alternative to conventional cigarettes, it is also important to have sensible rules on the quality of flavours used as unchecked use of flavourings could increase the risk profile of the product.

As a general rule, flavourings, whether natural or artificial, should be of food grade under local legislation. Where natural or naturally extracted flavourings are used, these should be subjected to an additional toxicological risk assessment.

Of course food grade flavourings rules do not take into account inhalation, but nevertheless they set a suitable minimum purity and safety standard when considered alongside the requirement for toxicological risk assessment of the vapour.

Of note, it may not be necessary to repeat the quantitative consideration for the same flavouring compound over and over again, so large elements of toxicological risk assessments can be reused across a wide range of e-liquid products using the same ingredients.

Given that food colouring is not an vital element for the e-liquids appeal and that we know nothing about their impact on the risk profile of the product when inhaled, it would make sense to avoid using them. Alternatively, these must be subjected to additional toxicological risk assessments.

Advice for Smokers

vaping or smoking health comparison JD: Given the various studies that have been released about ecigarettes (not limited to metals in ecigarette vapour), what would you advise a cigarette smoker who was considering switching to ecigarettes, but was worried by potential health risks associated with ecigs?

RP: An international expert panel convened by the Independent Scientific Committee on Drugs has recently provided an estimate of the relative importance of different types of harm related to the use of 12 nicotine-containing products, including e-cigs.

Tobacco cigarettes were found to be by far the most harmful and the e-cigs among the least harmful. Hence, to a cigarette smoker considering switching to e-cigs, but worried by potential health risks I would simply say

“if the health risk associated with tobacco smoking is equal to 100, vaping health risk is 4. The choice is yours”.

Health risk with tobacco smoking = 100, vaping = 4. The choice is yours – Prof. Polosa

relative nicotine harms e cigs

Ecig Regulation

E Cigarette Regulation Product PolosaJD: Both the anti-vaping lobby and the ecigarette industry agree there is need for regulation. However, the anti-vaping lobby want licensing enforced by MHRA, whilst the ecigarette industry would prefer trading standards to continue regulating and no licensing be implemented, as this would allow for continued innovation and choice whilst also maintaining the quality and safety. Do you think there could be a compromise reached?

RP:  As always “in medio stat virtus” – virtue stands in the middle.

Regulation for e-cig quality and safety standards do not necessarily imply medical licensing. Standards of products and e- cig industry practices have been raised substantially in the last 2 years in the absence of any mandatory regulation. This was mainly driven by the need to increase consumer confidence and to provide appropriate protection of the health and safety of users.

Of course, this can be further improved. But the next level of improvement requires intelligent risk-based trade-offs so that the appeal of e-cigs relative to tobacco cigarettes is enhanced and the innovation, diversity and competition in low risk alternatives to smoking is promoted.

Governments should simply regulate the e-cig as a consumer product, subject to a legislation that ensure adequate protection of the health and safety of users.

Ecig Industry Challenges

JD. I know you have been meeting with the ecigarette industry recently. In your opinion, what other challenges does the industry face, and what steps can the industry take to eliminate avoidable risks such as metal in vapour?

RP: In my opinion, the key challenge that the industry has to face in improving e-cig quality and safety standards in the near future is that of minimizing generation of potential thermal degradants of the diluents and of trace levels of metals from the atomiser.

Product innovation will bring solution to these challenges. Real-time temperature control of the heating element and non-metal alternatives to current atomiser metal alloys are now a reality and will be available to the consumer very soon.

I hope you’ll join me in saying thank you to Riccardo Polosa for once again giving up his time to explode vaping myths.

As with all our interviewees, Riccardo hasn’t been paid for his time or his expertise, and is one of a number of scientists that have given substantial amounts of time and, in some cases, risked their careers in the cause of tobacco harm reduction.

These scientists, in my opinion, are the true public health heroes.

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12 thoughts on “Metals In ECigarette Vapour: Do You Need to Worry?

  1. This I’d exactly what needs to be presented to the fda in the united states and related regulatory bodies world wide. I feel more studies that show this information needs to given to the general public to counteract the fear mongering that’s been done so far. Thank you for the post James it give me hope for the future.

  2. I have wondered if any one would ever want to look at my lungs for the following reasons.

    A long time asthma sufferer and childhood bronchitis sufferer, I had what doctors used to call “a weak chest” as it didn’t take much to cause an infection and I ended up in hospital many times as a young child because of it.

    I smoked for 42 years, strangely, in my younger years, smoking depressed the asthma but when the asthma fought back, it would floor me and I still suffered from often chest infections.

    When I started vaping, I was on two inhalers a day PRN 4 times, terrible barking cough all the time, constant infections that would persist for months.

    Within a month of ceasing smoking and using 36mg e-cigs instead, I went my first day of not needing my asthma inhalers AT ALL! And whilst its still there, I occasionally, say once a month need a puff off me blue one.

    Now it doesn’t take a genius to work this out, that a chronic asthma sufferer that suddenly improves with giving up cigarettes is a bit of a no brainer but my GP believes that e-cigs helped the transition and she said that other studies are finding beneficial results for our lungs and bronchial systems and she admitted there was a fierce war going on in medicine between the big pharma who are ripping our government off for billions with useless NRT and the emerging e-cig lobby who still has no real corporate support or government support which would enable them to stand up against the relentless attack by the nay sayers.

    This constant drip drip of “metal” dangers is annoying, the claims along the lines of brass inhalation equates to metal fume fatigue is one such instance, for a person to develop MFF, they have to inhale molten droplets of brass, copper and steels every day, many hours of a day to develop this illness, the little coil wire inside the ecig is designed to glow at about 200 degrees which isn’t enough even to make lead sweat and nowhere near the 600 degrees needed to make it liable to lose particles freely, lead in brass needs to be nearer the 800 degree mark and nickel, chromiums are metals designed to have a high melting point as well, its why they glow without melting.

    So as you can see, and this in a country where our water is fed through a copper and brass system in all but few houses, we have more to fear from our tap than our e-cig in my opinion.

  3. Dear Ian,

    Your personal story should provide inspiration to pharmaceutical industry to start investigating these products as a mean to improve control of airways diseases.

    Please keep in mind that ironically many people experience transient (days/weeks) worsening of respiratory symptoms (cough, wheezing, chest tightness) after quittin. Cough and breathlessness have been reported when switching to e-cigs, but progressive improvement in respiratory symptoms is usually observed with regular use of these products.

    If you are interested to learn more about the effect of regular vaping in asthma, please have a look at this recent study:


    1. Thank you, I will read that with interest as even the doctors had to admit that what they were told and what they saw were two different things.

      My GP suggested I should start a local vaping support group for those that choose the path, I might just do that 🙂

  4. So basically, if we assume that the “hour’s worth of continuous vaping” is roughly equal to a day’s worth of normal intermittent vaping, we’re saying that you’d have to vape for roughly 40,000 days, i.e. for over a CENTURY just in order to get the PERMISSIBLE DAILY LIMIT of exposure for heavy metals. Note that that’s not a HARMFUL amount… it’s specifically the “not harmful,” permissible amount.

    – MJM

  5. Brilliant interview. Damn but the media folks are good at fear creation aren’t they. Remember reading one article years ago about this metal-particles-in-vapour complaint and actually got a bit worried. This was well after all the anti-freeze nonsense so I should have known better, haha. Have shared and bookmarked this page – it’s definitely the most well researched and comprehensive rebuttal of the trace metals argument. Thanks James and Dr. Polosa!

  6. I have not had time to go further with my metals research, but I *DID* just run across a very interesting story that’s popped up in the last few days about FORMALDEHYDE! Formaldehyde is one of the nasties that some of the studies have tried to pin to e-cigs, and they haven’t had a whole lot of success.

    BUT… if you go to Google and enter:

    formaldehyde air gyms

    just like that you’ll see a bunch of new news stories about how formaldehyde is not only PRESENT in the air of your local health club, but it is likely to register significantly ABOVE SAFE LEVELS as all those selfish athletic types pump their respiratory and perspiratory waste products into the air that other patrons and the poor folks who are forced to work in such places must breathe.

    Obviously indoor gyms must be closed down. There is nothing inherent nor necessary about indoor facilities for exercise, and there is, as we all know, “no safe level” of exposure to such airborne carcinogens as formaldehyde — thus mere ventilation or air-filtration is ineffective as a solution and likely only to be pushed by Big Sweat and its minions.

    – MJM

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