Thirdhand smoke is a toxic residue that sticks to surfaces and objects. People and pets come into contact with thirdhand smoke when their skin touches a surface where thirdhand smoke has collected, when they breathe in thirdhand smoke chemicals that are in the air, and when they swallow residue that are on objects that they put in their mouths. Exposure is most dangerous for babies, children, the elderly, and individuals with pre-existing health conditions.
On this page, you will find scientific information and first-hand accounts about preventing human exposure to thirdhand smoke. We also provide communication strategies for talking with others about thirdhand smoke dangers.
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If nobody around me smokes, can I still be exposed to thirdhand smoke?
Thirdhand smoke is the chemical residue from tobacco smoke. It is also called “tobacco smoke residue” or “stale tobacco smoke.” The chemicals in thirdhand smoke are toxic to humans, especially children. Thirdhand smoke can linger for years in dust and on household surfaces. It can also become embedded in carpets,...
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Using Machine Learning to Differentiate Second- and Thirdhand Smoke Exposure
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Can thirdhand smoke hurt my pet?
The harmful effects of second- and thirdhand smoke exposure on people are widely known, but the same effects can apply to cats, dogs, and even birds and fish! Most pet owners protect their pets from tobacco smoke because they know that as they breathe in secondhand smoke in the air, they inhale hundreds of carcinogenic toxic chemicals.

















