Secondhand Smoke Vermont Department of Health Don't Be Fooled, E cig Aerosol Is Not Harmless for Kids American Lung Association Secondhand smoke and secondhand aerosol Many people assume vaping is harmless to bystanders, but secondhand aerosol can contain ultrafine particles and chemical residues. Researchers are examining how exposure may affect airways and overall health, especially for children How secondhand smoke, thirdhand smoke & vaping affects kids