Electronic cigarette (e-cigarette)

E-cigarettes, also known as electronic nicotine delivery systems (“ENDS”) or electronic non-nicotine delivery systems (“ENNDS”), are battery-powered devices that heat a solution (called the “e-liquid”) in a cartridge (also known as a “tank”) with a metallic coil to deliver an aerosol that users inhale through a mouthpiece in a way that simulates the act of cigarette smoking.  They may look like conventional tobacco products such as cigarettes or cigars, or they can take the form of other ordinary items such as pens, USB memory sticks and other larger cylindrical or rectangular devices.  The e-liquid is a chemical mixture typically composed of propylene glycol, glycerin, flavourings, and other additives.  E-cigarettes do not contain tobacco but ENDS contain nicotine.

(i) Harmful effects of e-cigarettes

There is now conclusive evidence that, in addition to nicotine, most e-cigarette products contain and emit numerous potentially toxic substances which are harmful to health.  Studies have demonstrated that formaldehyde, an irritant and cancer-causing chemical, could be formed during “vapourisation” of e-liquids.  Besides, most e-cigarettes contain propylene glycol, a known irritant when inhaled.  Inhalation of irritants may induce airway disorders such as asthma and other inflammatory lung diseases.  The use of e-cigarettes becomes addictive with the presence of nicotine and increases cardiovascular risks.

Long-term use of e-cigarettes is expected to increase the risk of various heart and lung diseases, cancers as well as some other diseases associated with smoking.

To date, research on the efficacy of e-cigarettes for smoking cessation is inconclusive.

(ii) Gateway and renormalisation effects

E-cigarettes are colourfully packaged and flavoured to increase their appeal to youngsters, and are promoted as being cool and fun.  Even though e-cigarettes on the local market should be nicotine-free, the design of such products, which simulates the behavioural and sensory characteristics of conventional cigarette smoking, may familiarise users with the act of smoking who may eventually progress to smoking conventional cigarettes. (1) Studies showed that adolescents who user e-cigarettes have greater risk of starting to smoke compared with non-user. (1, 2)

(iii) Growth and prevalence of e-cigarettes use

E-cigarette sales worldwide are increasing rapidly.  In 2014, ENDS reached US$2.76 billion in sales globally, (3) US$8.61 billion in 2016 and is expected to reach US$26.84 billion by 2023. (4)

Increasing trend in the use of e-cigarettes has been observed in different countries.  For example, in the United States, current e-cigarette use among high school students increased from 11.7% in 2017 to 20.8% in 2018, representing a 78% increase. (5)  In September 2018, the US Food and Drug Administration declared that “e-cigarette use among youth has hit epidemic proportions”.

(iv) Local consumption of e-cigarettes

According to the Thematic Household Survey Report No. 64 issued in April 2018, some 5 700 persons aged 15 or over were daily smokers of e-cigarettes, compared with the findings in 2015 of less than 1 000 persons aged 15 or above, more than a five-fold increase.

According to the School-based Survey on Smoking conducted by the School of Public Health, the University of Hong Kong in 2016-2017, 2 340 Primary 4-6 students (1.4%) had ever used e-cigarettes.  The number of ever and current e-cigarette users among Secondary 1-6 students was 29 380 (8.7%) and 2 770 (0.8%) respectively.  Among those primary school students who had ever used both e-cigarettes and conventional cigarettes, nearly 70% tried e-cigarettes first.

(v) Recommendation of the World Health Organization (“WHO”)

The seventh session of the Conference to the Parties to the WHO Framework Convention on Tobacco Control held in November 2016 proposed to its member countries to apply regulatory measures either to prohibit or restrict the manufacture, importation, distribution, presentation, sale and use of e-cigarettes, as appropriate to their national laws and public health objectives.

(vi) Prohibition on the use of e-cigarette in non-smoking areas

Cigarette smoking (including e-cigarette) is banned in no smoking areas under the Smoking (Public Health) Ordinance (Cap. 371).  Offenders are subject to a fixed penalty of $1,500.

Members of the public are reminded not to use any tobacco products and smokers are encouraged to quit smoking.  For more information on smoking cessation, please call the Integrated Smoking Cessation Hotline of the Department of Health at 1833 183.


(1) Primack BA, Soneji S, Stoolmiller M, Fine MJ, Sargent JD. Progression to traditional cigarette smoking after electronic cigarette use among US adolescents and young adults. JAMA pediatrics. 2015;169(11):1018-1023.

(2) Conner M, Grogan S, Simms-Ellis R, Flett K, Sykes-Muskett B, Cowap L, et al. Do electronic cigarettes increase cigarette smoking in UK adolescents? Evidence from a 12-month prospective study. Tobacco Control. 2018;27(4):365-72.

(3) Statistics and market data on Consumer Goods & FMCG.

(4) Electronic Cigarette Market by Product Type, Flavor and Distribution Channel – Global Opportunity Analysis and Industry Forecast, 2017–2023.

(5) Cullen KA, Ambrose BK, Gentzke AS, Apelberg BJ, Jamal A, King BA. Notes from the Field: Use of Electronic Cigarettes and Any Tobacco Product Among Middle and High School Students — United States, 2011–2018. MMWR Morb Mortal Wkly Rep 2018;67:1276–1277. DOI: