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. What you should know about vapes and e cigarettes Toxicological Effects of E Cigarettes on Cells, Animals, and Humans and Mechanisms of Toxicity Springer Nature Link Johns Hopkins Medicine Team Proposes Ways to Regulate and Better Manage E Cigarette Use Johns Hopkins Medicine The impact of e cigarettes versus traditional cigarettes on long term cardiopulmonary outcomes American Journal of Physiology Heart and Circulatory Physiology American Physiological Society