Vaping is often marketed as a safer alternative to smoking, but many vape products contain nicotine, harmful chemicals, and heavy metals that can harm developing brains and lungs. E Cigarettes, Vaping and Chew FAQ's Medical Clinic Marquette University Gasping for Action A Watchdog Report Lab tests reveal popular e cigarette liquids contain harmful chemicals Are they safe to inhale?': Vaping liquids in Canada contain potentially harmful chemicals, tests show CBC News The Truth about Vaping