Thirdhand Smoke: An Emerging Health Risk

young baby with fingers in mouth

Since 2009, attention has turned to the health effects of tobacco smoke residue that lands and is left on surfaces such as walls, ceilings, furniture, clothing, and even hair and skin long after cigarettes are extinguished. This leftover contamination has been dubbed thirdhand smoke.

Smoking and secondhand smoke exposure are harmful. But, research studies are now showing that this residual contamination from tobacco smoke also contains toxins that can have serious health effects, up to and including DNA damage in nonsmokers who are exposed to thirdhand smoke. In addition, numerous studies have demonstrated that the toxins in tobacco smoke can mix with chemicals present in the environment, resulting in the creation and emission of new, dangerous chemical compounds.

The risk of thirdhand smoke exposure is of special concern wherever children are crawling or playing, due to the risk of them touching contaminated surfaces and then putting their hands in their mouths or touching their eyes.

Testing has shown that the homes, hair, clothes, and cars of smokers can have significant levels of thirdhand smoke contamination, even at times when no one is actively smoking, and that residue remains for months. Tobacco smoke contaminants exist outside, as well as in indoor spaces. Residue has been found outside in dust where smoking has occurred, raising fresh concerns for establishing smoke-free environments in outdoor spaces where children and infants play.


Photo credit: The image on this page was taken by Roy Caruana-Clark of Oldham, Greater Manchester, United Kingdom, and was downloaded from his webpage (