Understanding Secondhand Vape Dangers and Their Impact on Your Lungs Scripps Health E cigarettes remain the most commonly used tobacco product among middle and high school students in the United States, according to the Instagram The Issues of Testing for Secondhand Smoke. Indoor Science According to a Centers for Disease Control and Prevention (CDC) study, 40% of U.S. adults believe that children's exposure to secondhand aerosol from e cigarettes causes only some or little harm, and 5%