Vaping is probably bad for your heart What's in an E Cigarette? American Lung Association 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 The New Look of Nicotine Addiction: Talk with your kids about the dangers of vaping Vaping leaves cancer causing chemicals in lungs, study shows