High concentrations of flavor chemicals are present in electronic cigarette refill fluids Scientific Reports A Comprehensive Review of the Harmful Compounds in Electronic Cigarettes JUUL E Cigarettes Harrison County Health Department Massachusetts new vaping campaign done with student input masslive.com E Cigarettes and Vaping OHSU 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.