Carcinogenic Potential of E-cigarettes: Vapor Profile and Cellular Effects

Abstract

E-cigarettes are devices that vaporize a liquid made of polyglycerol, glycol, flavorings, and nicotine, for inhalation. Initially created for smoking cessation, the health risks of these devices are still not clear. This literature review compiles data on the chemical profile of e-vapor and cell exposure studies to formulate conclusions regarding cancer risk and provide suggestions for future research. The reviewed studies identified a large range of potentially harmful compounds, namely formaldehyde, acrolein, and acetaldehyde, which were found in all studies. Metabolites of these compounds were then identified in exposed patients, showing bodily absorption. In vitro studies found evidence for cellular damage, including DNA mutations, reduced cell viability, and differentiated protein expression which may increase user’s cancer risk. Though the evidence is inconclusive given the heterogeneity of the field. Future studies should focus on the human effects of vaping, testing bronchial brushings and lavage fluid from users to determine the in vivo effects of exposure. Closely monitoring e-cigarette users for early warning signs of cancer would also help us understand future risk and answer questions about the safety of these devices.