E Cigarettes and Vaping PPAC Central Cigarettes or vapes, pick your poison Fred Hutch Health Risks of E Cigarettes and Vaping American Lung Association Toxicity of humectants propylene glycol and vegetable glycerin in electronic nicotine delivery systems ScienceDirect Vaping and e cigarette use is a troubling trend Fort Plain Central School District E liquid The Benefits of Vegetable Glycerin and Propylene Glycol Eliquidstop