A Comprehensive Review of the Harmful Compounds in Electronic Cigarettes

Electronic cigarettes (e-cigarettes) are devices designed to vaporize a liquid solution, offering an alternative to traditional tobacco consumption. The identification, detection, and analysis of the compounds present in these devices are crucial for understanding their impacts on health and the environment. Numerous studies have identified a diverse range of compounds emitted by e-cigarettes, including well-known substances such as nicotine, thermal degradation products, and other toxicants that may be harmful or carcinogenic. Although e-cigarettes are often considered an alternative to conventional smoking, they are not without risks. Recent research has increasingly focused on assessing the health impacts of e-cigarettes, integrating findings from various scientific disciplines. Two primary analytical approaches are used for the sample preparation, identification, and quantification of these compounds. The first approach focuses on aerosol analysis, utilizing techniques such as headspace static extraction and gas chromatography coupled with mass spectrometry (GC-MS). The second approach is directed towards liquid analysis, employing liquid–liquid extraction techniques and liquid chromatography (LC) systems. Given the constant publication of new research in this area, a comprehensive review that consolidates information on identified compounds, sample preparation methods, and extraction and analysis techniques is necessary to integrate current knowledge and address emerging findings.