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E-Cigarettes the Good, the Bad and the Ugly

Electronic cigarettes (e-cigarettes) have taken the world by storm, and vape shops are everywhere to be found. There are over 500 brands of e-cigarettes and 7700 flavours e-juice readily available on the market today. Their use has increased substantially, conspicuously in teenagers. Needless to say, many questions have been raised regarding the safety and health implications of these newer nicotine alternatives. Although Nicotine Replacement Therapy (NRT) medicines, which help people quit smoking, have been around for some time, e-cigarettes have become way more popular

An e-cigarette or vapour cigarette is a battery-operated, smoke-free, nicotine-delivering device resembling the real McCoy. However, instead of burning tobacco, it heats nicotine-containing liquid chemicals to produce a discerning vapour for one’s inhalation pleasure. That is why using an e-cigarette is also known as vaping.

People continue to smoke because they become addicted to nicotine. The tar-containing ingredients in conventional cigarettes are hazardous and therefore e-cigarettes were designed to provide smokers with the nicotine fix they crave, without the harmful effects. Since the launch of these alternative tobacco products, which come in various flavours and devices, there has been a slow but steady decline in cigarette smoking. E-cigarettes are promoted as a healthier alternative to regular cigarettes. Because you do not burn any tobacco, there is no smoke, odour or carbon monoxide. Long term, they may cost less than cigarettes and be a safer alternative for those struggling to quit. They seemingly have fewer second-hand effects, especially considering the smell, although they still produce vapour. Exposure to metals in the vapour does not seem to be a significant health concern. The re-usability of e-cigarettes may make them more environmentally friendly than traditional cigarettes, but limited information is available on the production, use and disposal imprint on the environment.

The Centre for Disease Control and Prevention (CDC) states that current evidence does not support the use of e-cigarettes as a safe alternative to quitting smoking. The Royal College of Physicians reports that e-cigarettes do not seem to be an effective aid to stopping smoking – at least in Britain. Along similar lines, a recently published review in The Lancet indicates that e-cigarette users were notably less likely to quit smoking. Anecdotally, however, many ex-smokers say e-cigarettes were the only thing that helped them to stop smoking eventually. So, although the final word is not out yet, e-cigarettes have not yet been approved as a way to quit smoking (contrary to popular belief). One of the issues is that people seem to use them only in situations where they are unable or prohibited to smoke, but then continue to use cigarettes where they are permitted to do so. The different flavours available make it appealing for teenagers to use e-cigarettes and it is feared that this may lead to the use of other tobacco products.

Although e-cigarettes have only been on the market for around 10 years, some worrying potential health and safety concerns have already been raised. The professed notion that these newer products are safer and less detrimental to one’s health seems to be uncertain as more data becomes available. A study recently published in Environmental Health Perspectives from the Harvard School of Public Health shows that although they do not contain the same tobacco carcinogens of regular cigarettes, they may carry other health risks. Almost all e-cigarettes contain nicotine and those that claim not to have been found to contain trace amounts. Some devices deliver higher concentrations of nicotine than others due to the different quantities used in the various brands; they are even mislabelled sometimes. Nicotine is highly addictive, and can have effects on the heart and circulatory system, lungs, certain hormones and the central nervous system. It has indirect effects on the developing brain through the rewiring of the brain circuitry, which can cause cognitive impairment, problems with working memory and attention, plus behavioural issues in youngsters. It also affects maternal and foetal well-being. The liquid nicotine that is used in these devices is extracted from tobacco and can be lethal when inhaled, ingested or absorbed through the skin. There has been an alarming increase in calls and visits to poison and emergency centres from accidental poisoning through inhalation and ingestion, especially in young children.

Apart from nicotine, e-liquids may contain flavourings, propylene glycol, glycerine, carbonyl compounds and volatile organic compounds. Traces of these solvents may cause lung irritation; however, even more worrisome is the thermal breakdown involved, which leads to the production of carcinogenic carbonyls like formaldehyde. The table below shows that formaldehyde levels are much lower than those found in tobacco smoke. However, the newer,
second-generation, maximised-power devices show much higher concentrations than older models.

Additionally, microscopic aerosol particles, similar to those of tobacco smoke, are inhaled and deposited in the small, deep airways of the lungs. These nanoparticles can trigger inflammation, possibly leading to cardiovascular disease and lung conditions. Some of the flavourings used, such as diacetyl, acetoin and acetyl propionyl (2,3-pentanedione), collectively known as diketones, are chemical additives used in the flavouring industry to provide a buttery or creamy flavour. Though they are considered safe for ingestion, there is no evidence on their safety when inhaled and they have also been linked to lung disease.

There have been numerous reports of e-cigarette batteries overheating, catching fire and even exploding, and some have resulted in severe burns. Nearly all of these problems arise from prolonged charging, the use of incompatible chargers or design issues that cause malfunction.

Severe nicotine poisoning from ingestion can cause nausea, vomiting and arrhythmias, and can even progress to seizures, respiratory depression and death. Nicotine exposure during pregnancy can result in preterm labour, low birth weights and even stillbirth. It is also considered a contributing factor in sudden infant death syndrome.

Lung health remains an issue with e-cigarettes. Reduced lung function, increased airway resistance and cellular inflammatory changes have been noted, comparable to that of tobacco smoke exposure. Another alarming, recent finding is that the nicotine-rich vapours cause bacteria to secrete thicker biofilms for protection against our natural defence systems, thereby making the bacteria more potent and increasing their resistance to antibiotics. This makes them harder to kill. Lipoid pneumonia and acute eosinophilic pneumonitis have also been linked to e-cigarette use.

Diacetyl is dangerous when inhaled and is known to cause serious, irreversible damage to the tiniest airways in the lungs, leading to a rare lung disease called bronchiolitis obliterans which presents with heavy coughing spells and shortness of breath. Referred to as “popcorn lung”, this was first described in workers who inhaled the artificial butteryflavouring in popcorn factories.

According to recent research by professor Irfan Rahman and his team, the chemical-containing vapour causes oral cells to release inflammatory proteins that act as stressors in the cells, leading to poor oral health, gum disease, loss of teeth and mouth cancer.

Although many claim that these are less harmful and can also help one to stop smoking, they still contain addictive nicotine and harmful chemical substances such as tobacco-specific nitrosamines. Their prolonged use can lead to health issues, including cancer of the mouth, oesophagus and pancreas, cardiovascular disease, gum disease and tooth decay. They also carry reproductive and foetal-development risks. It is a misconception that the water in hookah pipes filters the tobacco smoke, causing it to be less harmful. Smoking hubbly also carries the risk of potentially contracting an infectious disease. In addition, the nicotine and higher quantities of chemicals, including carbon monoxide and heavy metals, lead to addiction and health issues including cancer, heart disease and lung disease. Did you know that in an hour-long session of smoking water pipe, you can inhale 100-200 times the volume of smoke compared to that of one cigarette?

Vaping is safer than smoking, as the vapour contains much lower levels of toxic chemicals than in tobacco smoke. These lower levels may also be permissible around the office, according to workplace standards. However, these workplace-permissible standards are subject to change when vulnerable groups, such as children or the elderly, are present. E-cigarette sales to minors, vending machine sales and free samples are prohibited, in an attempt to protect minors from becoming part of the next generation hooked on nicotine. However, these measures do not prevent a minor from buying a device online.

With improved production standards and technological developments, the potential long-term health hazards of e-cigarettes could be reduced. Recent tighter regulation requires manufacturers to list ingredients, label the products with health warnings and acquire FDA approval before marketing their products. The Royal College of Physicians supports the UK Medicines and Healthcare Products Regulatory Agency’s announcement that e-cigarettes and
other novel nicotine products that are used as medicines should be regulated and subject to medical manufacturing standards. This is to ensure that these products are just as safe as other NRT products.

Any tobacco product is considered harmful until proven otherwise. Although e-cigarettes are less toxic and seem to be the lesser of the two evils when compared with regular cigarettes, they still cannot be considered safe. There is a lack of long-term safety data available, and the information we currently have is a complex mix of hypothetical harms and potential benefits. Our final recommendations are therefore as follows:
  • Age-restrict access to nicotine
  • If you choose to smoke, switch to vaping
  • If you vape, control the temperature of your model and use diacetyl-free, low-nicotine e-juice
  • Keep e-devices in a safe place, where children and pets cannot access them
  • Talk to your doctor about ways to quit
  • Last, but not least, if you do not smoke or vape, then continue to steer clear of these products

As soon as you quit smoking, your body begins to repair the damage caused by your habit. Below are the health benefits you will experience from 20 minutes after your last cigarette, up to 15 years after quitting.

Your heart rate drops to a normal level

12 HOURS: 
The carbon monoxide level in your blood drops to normal

Your risk of having a heart attack begins to drop
Your lung function begins to improve

Your coughing and shortness of breath decrease

Your added risk of coronary heart disease is half that of a smoker

Your risk of having a stroke is reduced to that of a non-smoker
Your risk of getting cancer of the mouth, throat, or oesophagus is half that of a smoker

Your risk of coronary heart disease is the same as that of a non-smoker

1. Arnold, C. 2014. Vaping and Health: What do We Know about E-Cigarettes? Environmental Health Perspectives, 122(9):245-249.
2. Cancer Net. 2016. Health Risks of E-Cigarettes, Smokeless Tobacco, and Water Pipes. [Online]. Available at: Health Risks of E-cigarettes, Smokeless Tobacco, and Waterpipes [Accessed: 3 August 2017].
3. CDC. 2017. Smoking and Tobacco Use. [Online]. Available at:
[Accessed: 3 August 2017].
4. American Lung Association. 2016. E-cigarettes and Lung Health. [Online]. Available at: [Accessed: 3 August 2017].
5. Raloff, J., Science News. 2014. Health risks of e-cigarettes emerge. [Online]. Available at: [Accessed: 3 August 2017].
6. Ross, J., Harvard Health Publications. 2016. E-cigarettes: Good news, bad news. [Online]. Available at: [Accessed: 3 August 2017].
7. Royal College of Physicians. 2016. Nicotine without smoke: Tobacco harm reduction. [Online]. Available at: [Accessed: 3 August 2017].
8. Kreiss, K. & Gomma, A. et al. 2002. Clinical Bronchiolitis Obliterans in Workers at a Microwave Popcorn Plant. The New England Journal of Medicine, 347:330-338.
9. Kalkhoran, S. & Glantz, S.A. 2016. E-cigarettes and smoking cessation in real-word and clinical
settings: a systematic review and meta-analysis. The Lancet Respiratory Medicine, 4(2):116-128.
10. Wikipedia. 2017. Safety of electronic cigarette. [Online]. Available at: [Accessed: 3 August 2017].
11. Vape Craft Incorporated. 2016. What You Need to Know About Diketones and E-Liquid Ingredients. [Online]. Available at: [Accessed: 3 August 2017].
12. The Consumer Advocates for Smoke-free Altrnatives Association. 2013. New study confirms thatchemicals in electronic cigarettes pose minimal health risks. [Online]. Available at: [Accessed: 3 August 2017].
13. U.S. Department of Health and Human Services. 2004. The Health Consequences of Smoking: A Report of the Surgeon General. Atlanta, GA: U.S. Department of Health and Human Services, Centres for Disease Control and Prevention, National Centre for Chronic Disease Prevention and Health Promotion, Office on Smoking and Health.

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Alex - February 15th, 2021 at 12:48pm

Great Article! Thanks for sharing great information about the e- cigarettes.


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