Broad evidence implicates e cigarettes as a cause of cancer Stanton Glantz blog Lung cancer risks persist with e cigarette use after quitting tobacco smoking The rise of teen vaping is worrying doctors worldwide. While e cigarettes were once marketed as a safer alternative, research shows they contain nicotine, heavy metals, and cancer causing chemicals that can damage developing Electronic cigarettes (e cigarettes) are sometimes called e cigs, vapes, vape pens, and electronic nicotine delivery systems (ENDS). E cigarettes come in many shapes and sizes. Most e cigarettes contain nicotine. Get the facts about e cigarettes, Misconceptions about e cigarette safety might be stopping smokers using them to quit