Electronic cigarettes (e-cigarettes or e-cigs) have recently become a popular alternative to smoking the conventional cigarette. Numerically speaking, there are now over 250 different e-cigarette brands which are being marketed as smoking cessation devices.

There is not yet sufficient research on their long-term safety but there is a great support for the opinion that e-cigarettes are approximately 95% safer than smoking.

Its effectiveness might partly be explained by the fact that e-cigs satiate both the addiction to nicotine and the behavioral aspect of smoking such as the actual hand-to-mouth movements.

General Information

E-cigs were invented and popularized by pharmacist Hon Lik in 2003. These devices have been designed to deliver nicotine with chemicals such as flavorings to users in the form of vapor. They are electrically operated using a lithium battery and their designs can be varied to emulate traditional tobacco cigarettes, cigars or pipes, or even pens or USB memory sticks.

E-cigarettes generally contain nicotine, a type of flavoring (molasses and fruit are common) and propylene glycol – a manufactured liquid used in food, cosmetics, and certain medicines to absorb water and help them retain moisture.

These e-cigs function by using a small, heated coil (atomizer) to vaporize a cartridge of liquid solution (usually containing a decided concentration of nicotine) into an aerosol mist. Users inhale the mist just as they would the smoke of an ordinary cigarette but they themselves are not exposed to tobacco, which turns into carcinogenic tar when burned.

E-cigarettes are very often promoted as safer alternatives to traditional cigarettes, which deliver nicotine by burning tobacco. Whilst these claims could very well be true, there is still much to be learned about the health risks of using these devices.

Addictive and Carcinogenic Agents

Whilst e-cigarettes do not produce tobacco smoke, they still contain the highly addictive drug, nicotine. Because of this chemical, stopping the use of an e-cigarette can result in withdrawal symptoms such as irritability, restlessness, depression, and anxiety. Furthermore, there has been research to suggest that nicotine exposure primes the brain to become addicted to other substances.

The refilling of cartridges containing e-liquid used by some e-cigarettes may also be a worrying aspect of their use. Users may expose themselves to potentially toxic levels of nicotine during the process of refilling them. Fortunately, the nausea and vomiting caused by relatively low doses of nicotine prevent more serious cases of poisoning.  Users may also be tempted to fill the cartridges with substances other than nicotine, in this way delivering other drugs to their system in a new and possibly dangerous way.

The testing of some e-cigarette products have observed the vapor to contain established carcinogens and toxic compounds (such as formaldehyde and acetaldehyde), as well as nanoparticles. These nanoparticles can be potentially toxic, likely arising from the solder joints or metal coil in the devices during the vaporizing mechanism. Should these nanoparticles of tin, chromium, nickel and other heavy metals be present in large enough concentrations, lung damage can be inflicted. This may be if they are able to travel deep into the lungs and worsen respiratory distress in those suffering from asthma, bronchitis and emphysema.

References

• http://www.nhs.uk/news/2015/08August/Pages/E-cigarettes-95-per-cent-less-harmful-than-smoking-says-report.aspx
• http://www.drugabuse.gov/publications/drugfacts/electronic-cigarettes-e-cigarettes
• http://www.scientificamerican.com/article/smoke-screen-are-e-cigarettes-safe/
• http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4687310/
• https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/457102/Ecigarettes_an_evidence_update_A_report_commissioned_by_Public_Health_England_FINAL.pdf

Further Reading

• All Electronic Cigarette Content
• Do E-Cigarettes Cause Cancer?

Written by

Afsaneh Khetrapal

Afsaneh graduated from Warwick University with a First class honours degree in Biomedical science. During her time here her love for neuroscience and scientific journalism only grew and have now steered her into a career with the journal, Scientific Reports under Springer Nature. Of course, she isn’t always immersed in all things science and literary; her free time involves a lot of oil painting and beach-side walks too.