190524 vaping dangers
Many smokers trying to quit smoking alternate between e-cigarettes and actual cigarettes, and it’s here that the younger generation may get lured by the sudden trend. Image Credit: Supplied

Dubai: Health care practitioners are worried that adolescents who were otherwise non-smokers might now get hooked to nicotine as the UAE plans to legalise the availability of e-cigarettes.

Dr Sree Kumar Sreedhaharan, internal medicine specialist at Aster Clinic Karama, who is a staunch anti-smoking supporter feels the legalisation of e-cigarettes will unleash a whole generation of new nicotine addicts.

“Most e-cigarettes contain nicotine, the addictive drug in regular cigarettes,” he said. “Nicotine can harm the developing adolescent brain. The brain keeps developing until about the age of 25.

“Using nicotine in adolescence can harm the parts of the brain that control attention, learning, mood, and impulse control,” he added. “Each time a new memory is created or a new skill is learnt, stronger connections — or synapses — are built between brain cells.

Using nicotine in adolescence can harm the parts of the brain that control attention, learning, mood, and impulse control.

- Dr Sree Kumar Sreedhaharan | Internal medicine specialist, Aster Clinic

“Young people’s brains build synapses faster than adult brains. Because addiction is a form of learning, adolescents can get addicted more easily than adults. The nicotine in e-cigarettes and other tobacco products can also prime the adolescent brain for addiction to other drugs.”

Many smokers trying to quit smoking alternate between e-cigarettes and actual cigarettes, and it’s here that the younger more impressionable generation may get lured by the sudden trend.

“There is some evidence that young people who use e-cigarettes may be more likely to smoke cigarettes in the future,” said Dr Sreedharan.

“The bottom line is, the use of any tobacco product, including e-cigarettes, is unsafe for young people. The American Cancer Society and the Food and Drug Administration (FDA) warn that no youth should use nicotine products.

“Most e-cigarettes contain nicotine and some that claim to be nicotine-free have also been found to contain nicotine,” he said.

What are e — cigarettes?

Electronic Nicotine Delivery systems (ENDS), are nicotine delivery devices designed to look and feel like a traditional cigarette, a pen or a fashion accessory. They are often marketed as tobacco-free. The difference between conventional cigarettes and e-cigarettes is that instead of burning tobacco, the user is able to inhale nicotine and other flavourings without any combustion. When a user switches on the e-cigarette, and draws air through the device or an airflow sensor, a physical power button activates a battery that powers an atomiser to produce an aerosol containing nicotine and other flavourings. An aerosol in broad connotation here means a substance enclosed under pressure and released as a fine spray by means of a propellant gas. This entire process has been dubbed as vaping.

What are the harmful chemicals that e-cigarettes contain?

In a study conducted by Dr Tianrong Cheng reviewing e-cigarettes at the Centre for Tobacco Products, FDA, USA, he stated: “Although deemed safer than cigarettes as these do not involve combustion as in conventional smoking, e-cigarettes contain a variety of toxic chemicals.”

Chemicals in e cigarettes are; nicotine, Tobacco-Specific Nitrosamines (TSNAs), aldehydes and metals, Volatile Organic Compounds (VOCs), flavours, solvent carriers, tobacco alkaloids in e-cigarette refill solutions and Phenolic compounds, polycyclic aromatic hydrocarbons and drugs in e-cigarette refil, solutions, cartridges and aerosols.

How each chemical affects the vaper?

Dr Sreedharan quoted several studies conducted on e-cigarette smokers and the potential harm unleashed by its chemicals.

Nicotine — The nicotine content of e-cigarettes and liquids varies and usually ranges from none (nicotine-free) up to 36 mg/ml, though it can be higher. Common nicotine concentrations of e-cigarette liquids are 6 mg/ml, 12 mg/ml, 18 mg/ml, or 24 mg/ml. The level of nicotine measured by chemical analysis has been found to be inconsistent with manufacturers package labelling. Cartridges labelled nicotine-free have nicotine. Nicotine exposure from e-cigarette use, as with cigarette smoking, increases heart rate and produces measurable levels of blood cotinine, a nicotine metabolite.

The amount of nicotine delivered and the level of nicotine in the blood varies depending on nicotine concentration in the e-cigarette liquid, other components in the e-cigarette liquid, user-experience, puffing intensity, device characteristics, and vaping technique.

Propylene glycol/glycerol

Propylene glycol or glycerol are humectants that are the main components of most e-cigarette liquids; some products may use ethylene glycol. Vapour exposure — e-cigarettes do not expose the user to many of the constituents of cigarette smoke (eg, tars, oxidant gases, and carbon monoxide) that are responsible for many of the tobacco-attributable diseases. However, most e-cigarettes do contain a number of potentially toxic chemical substances. Despite this, most experts believe that inhaling e-cigarette vapour is likely to be less harmful than inhaling cigarette smoke. The consequences of chronic inhalation of e-cigarette vapour is largely unknown, and levels of toxic and carcinogenic compounds may vary by e-cigarette liquid components and the device used.


Unlike conventional cigarettes, e-cigarettes can be sold with characterising flavours. More than 7,000 flavours are available, including candy, fruit, soda, and alcohol flavours. Flavourings may increase the attractiveness of e-cigarettes to youth, especially those who are not already smokers.

Other compounds

Metals such as tin, lead, nickel, chromium, manganese, and arsenic have been found in e-cigarette liquids and vapour. Other compounds detected include tobacco-specific nitrosamines, carbonyl compounds, metals, volatile organic compounds, and phenolic compounds.

Can e-cigarettes cause heart and cancer risk?

The long-term cardiovascular risks of e-cigarettes though unknown are thought to be substantially lower than the risks of smoking. Aerosol constituents that may influence this risk include nicotine, oxidising chemicals, particulate matter, and acrolein. A small observational study found that e-cigarette use for at least one year was associated with factors that have been correlated with increased cardiovascular risk and increased oxidative stress. It is not known whether the particles in e-cigarette vapour have any toxicity.

No observational data examining the long-term health effects (eg, risk of cancer) of e-cigarettes exist; however, there is awareness that use of e-cigarettes among adults poses fewer risks than does smoking traditional cigarettes.

Little is known about the overall safety or the carcinogenic effects of propylene glycol or glycerol when heated and aerosolised. At high temperatures, propylene glycol decomposes and may form propylene oxide, a probable human carcinogen. Glycerol produces the toxin acrolein, though the levels produced are lower than conventional cigarettes. Both propylene glycol and glycerol decompose to form the carcinogens formaldehyde and acetaldehyde, with levels depending on the voltage of the battery used in the e-cigarette. been found to contain nicotine.

Other carcinogenic compounds have been found in e-cigarettes but in trace amounts that are much lower than levels found in conventional cigarettes. These include tobacco-specific nitrosamines (TSNAs), carbonyl compounds, metals, volatile organic compounds (VOCs), and phenolic compounds. In one study, the level of TSNAs found in e-cigarettes was comparable with the level found in a nicotine patch. A small observational study found that users of e-cigarettes for at least six months who did not also smoke combustible cigarettes had substantially lower urinary and salivary concentrations of TSNAs and VOCs than did smokers of combustible cigarettes.

Respiratory stress

Limited evidence on the effects of e-cigarette vapour on respiratory function suggests that changes in airway respiratory function are much smaller than those associated with conventional cigarettes, but there may be an association with cough and asthma symptoms among adolescents. One survey study of over 45,000 students (mean age 14.6 years) in Hong Kong found that e-cigarette use was associated with respiratory symptoms (cough or phlegm), regardless of smoking status. Similarly, a survey of 11th and 12th-grade students in California found an association between self-reported chronic bronchitis symptoms (chronic cough, phlegm, or bronchitis in the past year) and current or past e-cigarette use that remained after adjustment for confounders such as cigarette smoking or secondhand smoke exposure; risk increased with frequency of current use of e-cigarettes.

The effect of inhaling flavourings on respiratory function is also uncertain. Some studies have found a link between cytotoxicity and certain flavourings used in e-cigarette liquids, especially sweet and cinnamon flavours. Specifically, diacetyl, a chemical associated with respiratory diseases, has been found in sweet-flavoured e-cigarettes. Cherry-flavoured e-cigarettes have been found to contain benzaldehyde, a compound that is associated with respiratory irritation.