E Cigarettes: A 'Gateway Drug' to Addiction FDA permits the marketing of an e cigarette for the first time, paving the way for vaping products to be legally sold in the U.S. Roswell Park Comprehensive Cancer Center Buffalo, E Cigarettes and Vaping Texas Poison Center Network From cigarettes to e cigarettes: The evolution of tobacco use in the United States 4 H Healthy Youth The Dangers of e Cigarettes Rendia Vaping Safety, Smoking, Dangers, Pros, Cons, Debate, E cigarettes, & Tobacco Britannica