Electronic cigarettes (EC) have gained popularity among smokers due to their taste, smell, appearance, and easy availability compared to traditional cigarettes, as well as the perception that they are safer than traditional cigarettes. These devices result in aerosols containing nicotine, propylene glycol, glycerin, ethylene glycol, vitamin E, and chemical flavors inhaled into the lungs. Other components found in these vapors include heavy metals such as nickel, chromium, lead, manganese, and tin. In addition, some ingredients volatilization leads to toxic aldehydes formation such as formaldehyde, acetaldehyde, and acrolein. Smoking cigarettes is addictive and has been associated with many health issues such as heart disease, lung cancer, etc. Rising awareness of these dangers moves more people towards these electronic delivery systems, reducing the health effects of cigarettes. The toxicity of EC’s ingredients is well studied when ingested; however, their toxicity through inhalation remains unclear. Consequently, the use of ECs has become a significant concern worldwide and raises whether it is indeed safe to use. This paper will serve as a literature review paper to discuss the toxicity of commonly found ingredients in ECs and their associated health issues. Our conclusion emphasizes that even though smoking EC is less risker than smoking traditional cigarettes, it is still not safe due to the potentially harmful effect these E-cig’s ingredients have on the human’s health. In addition, E-cigarette’s aerosol could also contain toxic compounds such as formaldehyde, acetaldehyde, and acrolein due to glycerin’s thermo-degradation.
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