Safety and Efficacy of Electronic Cigarettes: A Comprehensive Review of Toxicological and Clinical Evidence

Electronic cigarette (EC) products continue to undergo rapid technological evolution, and findings from earlier-generation devices may not be generalizable to newer models that incorporate higher battery capacity, adjustable voltage systems, and modified aerosolization mechanisms [1]. Variability in device engineering, nicotine formulation, and heating temperature significantly influences toxicant generation and nicotine delivery efficiency, thereby complicating direct comparisons across studies. In addition, marketing strategies, regulatory frameworks, and sociocultural influences differ between countries, contributing to heterogeneous patterns of EC uptake and variable public health consequences [2,3]. The overall impact of ECs must therefore be evaluated within the broader landscape of persistent combustible tobacco availability, widespread dual use of ECs and conventional cigarettes among adults and youth, and shifting perceptions of nicotine risk [2,3]. A comprehensive assessment of EC safety requires examination of toxicant exposure, pharmacokinetic nicotine delivery, respiratory and cardiovascular effects, and real-world patterns of use. Such evaluation is critical for the development of evidence-based regulatory policies aimed at protecting both smokers and nonsmokers, including vulnerable populations such as adolescents and pregnant women, particularly in light of aggressive marketing tactics employed by the tobacco and vaping industries [4]. Despite widespread promotional claims, current scientific evidence does not conclusively substantiate assertions that ECs are either harmless alternatives to combustible cigarettes or reliably effective smoking cessation tools [5]. Moreover, the potential for EC use to renormalize nicotine consumption and undermine existing tobacco control measures remains a public health concern. To minimize unintended negative consequences on prevention and cessation efforts, EC use should be restricted in environments where conventional smoking is prohibited, and regulatory oversight—including advertising and marketing restrictions—should be comparable to that applied to traditional tobacco products [6].