Analysis suggests e cigarette use may be linked to lower rates of smoking Vaping's Harmful Effects on Our Patients AAO HNS Bulletin E cigarettes contain hazardous substances, addictive and harmful Vaping is often marketed as a safer alternative to smoking, but many vape products contain nicotine, harmful chemicals, and heavy metals that can harm developing brains and lungs. Vaping releases toxic chemicals, including heavy metals, as well as ultrafine particles that go deep into the lungs. These increase the risk of heart and lung disorders.