Scientists Warn Against Breathing in Secondhand Vape 'Smoke' Newsweek Millions of people are exposed to secondhand smoke every day. People living in multi unit housing are some of the most exposed. The only way to fully protect people from secondhand smoke at Protecting Youth From the Harms of Vaping Smoking and Tobacco Use CDC Do electronic cigarettes create thirdhand chemical residue? Thirdhand Smoke Resource Center