Health effects of secondhand smoking (SHS) and tobacco smoke exposure (TSE)

Family members and caregivers who use tobacco products should be educated on the health effects of tobacco smoke exposure (TSE). TSE, a combination of secondhand smoke (SHS) and thirdhand smoke (THS), contributes to serious acute and chronic diseases in children, adolescents, and family members at every age. SHS is a combination of what comes off the burning cigarette and what a smoker exhales. Thirdhand smoke is the residue of SHS that sticks to walls, carpets, and furniture. All of these are harmful. Thirdhand smoke not only contains many of the same contaminants as SHS, but it also undergoes chemical transformations when it is exposed to gasses commonly present in homes to produce secondary, highly carcinogenic pollutants such as formaldehyde and tobacco-specific nitrosamines. Vape aerosol, which comes from the mouth of the person vaping, contains a mix of toxic compounds, some of which are the same as TSE, but most of which are different and not well studied. Vape aerosol contributes to proinflammatory particulate matter pollution in the air and settles on surfaces where the person vapes.

Infants and young children are especially vulnerable to harms related to TSE because they are still developing and they inhale more toxins based on their rapid respiratory rate and small body size. SHS also contributes to serious acute and chronic diseases, including sudden infant death syndrome, lower respiratory illness, impaired lung function, middle ear disease, stroke, lung cancer, coronary heart disease, and more frequent and severe asthma attacks. Offspring exposed to maternal smoking during pregnancy have low birth weight, greater risk of dying from SIDS, and a greater risk of ADHD and obesity later in life. Adolescents are also much more likely to start using tobacco products if their parents use those products. While less is known about secondhand vaping exposure, there are hundreds of toxins and chemicals in the aerosols that are harmful or potentially harmful to infants and children.