E cigarettes contain hazardous substances, addictive and harmful E cigarettes get a bad rap but scientists say they can be really helpful in 2 ways AOL Vaping versus smoking All E Cigarettes Emit Harmful Chemicals, but Some Emit More Than Others Berkeley Lab Berkeley Lab News Center From cigarettes to e cigarettes: The evolution of tobacco use in the United States 4 H Healthy Youth Awareness of vaping risks key to reducing e cigarette use among young people The George Institute for Global Health