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. Vaping Harmless. Vape aerosol contains toxic chemicals like formaldehyde, arsenic, lead, chromium, and nickel. They damage lungs. They harm developing brains. They raise cancer risks. We Health effects of electronic cigarettes Wikipedia Vaping 101: What Teens and Parents Need to Know GUIDE, Inc.