Ignore e cigarettes at your patient's peril Cleveland Clinic Journal of Medicine Vaping has become common, but it's important to know what you're inhaling. Many e cigarettes contain nicotine, heavy metals like nickel and lead, and chemicals that can harm your lungs and overall health. About E Cigarettes (Vapes) Smoking and Tobacco Use CDC Cabin Safety Electronic Cigarette For e cigarettes, public supports health warnings & ban on sales to minors National Poll on Children's Health