Thirdhand Smoke Resource Center Protecting Californians Secondhand Vape Exposure: Effects, Who's at Risk, and More Vape residue may harm unborn babies, mouse study suggests In the United States, about 8% of all women who are pregnant smoke cigarettes, and another roughly 4% report using electronic cigarettes or vapes. To learn more about the dangers of smoking What Chemicals Are Present in Secondhand Vape Emissions? E Cigarettes (Vapes) Smoking and Tobacco Use CDC