The Science 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 How Can Smoking and Vaping Impact Cancer? Urology Care Foundation 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, A analysis of more than 100 studies found the vaping can have long term health consequences.