What's in an E Cigarette? American Lung Association All E Cigarettes Emit Harmful Chemicals, but Some Emit More Than Others Berkeley Lab Berkeley Lab News Center In recent years, the number of e cigarette users worldwide has sharply increased, with many believing that vaping is less harmful than smoking traditional cigarettes. However, health experts are warning of its negative E cigarettes get a bad rap but scientists say they can be really helpful in 2 ways AOL