Juul vape: What is it, why are teens addicted, and is it safe? CNET A toxic, plastic problem: E cigarette waste and the environment E Cigarettes and Vaping Business Insider The Hidden Dangers: E Cigarettes, Heated Tobacco, and Their Impact on Oxidative Stress and AtherosclerosisA Systematic Review and Narrative Synthesis of the Evidence Vapes and e cigarettes often contain nicotine, heavy metals, and carcinogensand can harm developing brains, affect mood and learning, and lead to lasting lung damage. Just one hit can start an addiction.