Electronic cigarettes (E-cigarettes) are devices that deliver nicotine to a user by heating and converting to an aerosol a liquid mixture typically composed of propylene glycol, vegetable glycerin, flavoring chemicals, and nicotine. E-cigarette use doubled in just 1 year among both adults and children, from 3.4% to 6.2% in adults (2010–2011) and 3.3% to 6.8% in youth (2011–2012), with high levels of dual use with tobacco cigarettes. Although most youth using e-cigarettes are dual users, up to one third of adolescents who tried an e-cigarette have never smoked a conventional cigarette, indicating that some youth are initiating use of the addictive drug nicotine with e-cigarettes.
Smoke-free policies are a critical intervention both to protect nonsmokers and to support smoking cessation attempts. To avoid reversing the effectiveness of these policies, e-cigarettes should not be used anyplace where smoking cigarettes is not allowed (including in homes that are smoke-free). There is no reason to reintroduce toxins into clean indoor air environments.