E Cigarettes Vaping with Juul & Other Electronic Cigarettes Vaping, Smoking and Lead Poisoning Health Risks of Secondhand Smoke and Aerosols Factsheet US EPA Thousands of Unknown Chemicals Found in E Cigarettes Respiratory Therapy High concentrations of flavor chemicals are present in electronic cigarette refill fluids Scientific Reports All E Cigarettes Emit Harmful Chemicals, but Some Emit More Than Others Berkeley Lab Berkeley Lab News Center