Study suggests switching from smoking to vaping indoors may reduce children's secondhand exposure to nicotine Juul study shows secondhand vaping emissions are less toxic than cigarette smoke 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% Does cannabis create thirdhand smoke? Thirdhand Smoke Resource Center