Children absorb less secondhand nicotine through vapor vs. smoke E Cigs and Second Hand Vaping: Dangers and Protections 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 smoke and secondhand aerosol Experts Warn About the Lifetime Effects of Secondhand Smoke in Children CardioSmart American College of Cardiology