Secondhand smoke and secondhand aerosol Animal Study Shows Harmful Effects of Secondhand Smoke Even Before Pregnancy Duke Health Passive smoking (secondhand smoke) is extremely harmful to children, especially infants. Because infants breathe faster than adults, they inhale more smoke toxins per minute. This exposes them to dangerous chemicals like nicotine, Secondhand e cigarette aerosols expose kids to less nicotine than cigarettes, study finds, but can still be risky CNN Do electronic cigarettes create thirdhand chemical residue? Thirdhand Smoke Resource Center