E-Cigarettes: A Hazy Hazard

• Electronic cigarettes (e-cigarettes or e-cigs) are battery-powered devices that deliver vaporized nicotine and other substances, such as flavorings, to users without smoke or combustion. They are commonly marketed as smoking cessation tools and, as such, are promoted as being a healthier alternative to smoking. • A common misperception is that that e-cigarettes only release water vapor. In reality, though, these devices release nicotine and other chemicals in a vapor form that can expose both the user (a.k.a., the vaper), as well as those in the immediate vicinity, to those contaminants. While the health risks of e-cigarettes compared to regular cigarette smoking is greatly reduced, many toxic compounds are still present. • The rapid increase in use of electronic cigarettes has generated a potential concern for indoor air quality in that there is still limited data on potential exposures and human health risks for users, or for others through second- and third-hand exposures