There has been rapid growth in ever and current electronic cigarette use over the past 4 years. Use is highest among young adults and current cigarette smokers. Although smokers are most likely to use these products, almost a third of current users are nonsmokers, suggesting that e-cigarettes contribute to primary nicotine addiction and to renormalization of tobacco use. Regulatory action is needed at the federal, state, and local levels to ensure that these products do not contribute to preventable chronic disease.

Most children without known secondhand tobacco-smoke exposure inside the home still showed evidence of tobacco-smoke exposure. Children in apartments had higher mean cotinine levels than children in detached houses. Potential causes for this result could be seepage through walls or shared ventilation systems. Smoking bans in multiunit housing may reduce children's exposure to tobacco smoke.