Abstract
Dear editor,
E-cigarettes are often promoted as safer nicotine-delivery devices to help quit or reduce smoking. However, some hardcore smokers or ‘pro vapor’ groups claim that they switch to e-cigarettes as a means of reducing or quitting smoking without any intention to do so. Countries such as Brazil, Singapore, and Uruguay have banned e-cigarettes. However, in the United Kingdom and Malaysia, the use and sale of e-cigarettes is legal, with children even having direct access to them. It must be stressed that questions remain unanswered concerning the potential for e-cigarettes to harm as the e-liquid used in such devices contains nicotine and other potentially harmful chemicals. The liquid nicotine content in e-cigarettes is known to be harmful even at a low concentration. There is 8.5 to 22.2 mg/ml of nicotine in one e-cigarette cartridge, with the lethal dose for adults and young children estimated to be 30–60 mg and 10 mg, respectively. 1 However, the lack of labeled information on the exact amount of nicotine in each brand of e-cigarette cartridge inadvertently exposes smokers to nicotine intoxication. 1 Four of 20 brands of e-cigarette cartridges tested were found to contain nicotine, despite being labeled as nicotine free. 2 One study also found carcinogenic nitrosamines (usually found in tobacco) in e-cigarettes during the vaporization process. 3 Besides the risk from carcinogens, e-cigarette users may alter their normal pulmonary homeostasis as a result of an immediate decrease in the fraction of exhaled nitric oxide concentration and an increase in lung flow resistance. 3 Propylene glycol and glycerol, which are the main liquid components for the vaporization of the e-liquid, are converted to formaldehyde and acrolein through a process of heating and vaporization. Vaping e-cigarettes for only five minutes among healthy smokers can cause resistance in peripheral airway flow and oxidative stress. Furthermore, the flavoring agents in e-cigarettes might increase the risk of developing bronchiolitis obliterans, an irreversible respiratory disease. 4
Tobacco control experts fear that e-cigarettes are used as a ‘gateway drug’ that makes users more inclined to start smoking conventional cigarettes and became addicted to nicotine, marijuana, cigars, or other dangerous products. Several studies have also reported a negative impact of e-cigarette vaping on indoor air quality and health. 3 Nicotine and propylene glycol in e-cigarettes can damage the health of passive smokers as it exceeds the limit of chronic Reference Exposure Level (CREL) hazard quotients (the ratio of the potential exposure to a substance to the level at which no adverse effects are expected 3 – used as an indicator for non-cancer health effects). The concentration of airborne nicotine in a conventional smoker’s home was found to be statistically higher than in an e-cigarette smoker’s home. However, the concentration of biomarkers was statistically similar among non-smokers in both homes. Trace amounts of airborne nicotine were also detected in e-cigarette smoker’s homes (compared to none in a non-smoker’s home). 5 These findings clearly show that e-cigarettes pose harm to the users and the people around them. In order to combat the use of e-cigarettes and other forms of tobacco use, e-cigarettes should be regulated by the law accordingly in terms of advertising, promotion, packaging, and labeling to ensure the maintenance of appropriate environmental and public health. Additional data on the long-term effects of e-cigarette use are needed and consumers should be warned on the potential health risks associated with e-cigarettes.