Tobacco, Nicotine, and E-Cigarettes Research Report
What are the effects of secondhand and thirdhand tobacco smoke?

Secondhand smoke is a significant public health concern and driver of smoke-free policies. Also called passive or secondary smoke, secondhand smoke increases the risk for many diseases.55 Exposure to environmental tobacco smoke among nonsmokers increases lung cancer risk by about 20 percent.48 Secondhand smoke is estimated to cause approximately 53,800 deaths annually in the United States.55 Exposure to tobacco smoke in the home is also a risk factor for asthma in children.56

Smoking also leaves chemical residue on surfaces where smoking has occurred, which can persist long after the smoke itself has been cleared from the environment. This phenomenon, known as "thirdhand smoke," is increasingly recognized as a potential danger, especially to children, who not only inhale fumes released by these residues but also ingest residues that get on their hands after crawling on floors or touching walls and furniture. More research is needed on the risks posed to humans by thirdhand smoke, but a study in mice showed that thirdhand smoke exposure has several behavioral and physical health impacts, including hyperactivity and adverse effects on the liver and lungs.57