The safety and efficacy of Electronic cigarettes in smoking cessation

Although electronic cigarettes are increasing in popularity all over the world, their safety and efficacy for smoking cessation have remained unclear and discussed in scientific literature. The aim of present study was to review the available evidence about the use, content, safety of ECs and their potential effects on users' health, and the extraction of resources to guide and assist future decisions and policies.       This review was conducted by assessing the safety and efficacy of ECs in English databases of PubMed, Elsevier, Proquest, Google scholar, Google's search engine, other websites and also in Persian databases of SID and MagIran.         ECs are tools designed to deliver nicotine without heating and toxic substances in tobacco smoke, enabling some users to reduce or stop smoking. Nevertheless, there is alittle knowledge and information about the short-term and long-term effects of ECs on health. However, some studies have shown that the aerosols, cartridges, refill liquids, and gases released from these cigarettes contain chemical substances and ultrafine particles that have an acute effects on the cardiovascular system and pulmonary function, as well as the risk of cancer.            Allowing ECs to compete with traditional cigarettes in the market can reduce the mortality and disease caused by smoking. However, the health effects of ECs are unknown and may encourage young people to dual use of EC and traditional tobacco. Since most studies focus on acute EC-related health problems, further research is needed to explore the safety and potential of long-term use and utility as a cessation tool.