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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USC Physician Explains the Importance of 100% Smokefree Environments
Dr. Ching-Fei Chang, a pulmonologist at Keck Medicine at USC discusses the dangers of exposure to toxic second- and thirdhand smoke.

Berkeley National Laboratory Researchers Demonstrate Thirdhand Smoke Link to Lung Cancer Development
Exposure to thirdhand smoke during infancy and childhood increases one’s risk of developing of lung cancer in adulthood. More research is needed to understand the link between exposure to thirdhand smoke in childhood and development of disease later in life.


Thirdhand Smoke—Ten Years Later
Ten years ago, the New York Times Magazine highlighted “thirdhand smoke” in its annual “Year in Ideas” issue, which takes a look back at the past year through innovations and insights from a wide variety of fields. Since then, teams of researchers world-wide have produced more than 100 scientific studies related to thirdhand smoke, reinforcing and expanding the concerns raised in 2009.

New Video from TobaccoFreeCA Explores Californian’s Understanding of Secondhand Smoke
What do Californian’s know about secondhand smoke, the precursor to toxic thirdhand smoke? Reporter Belgica Rodríquez took to the streets to find out, and what she learned may surprise you.

Physicians Across the US Support Protection from Thirdhand Smoke Exposure
Last month, America’s frontline physicians who provide the overwhelming majority of health care to our nation adopted principles regarding policies to reduce harm associated with tobacco products. The principles recognize that tobacco use harms not just users and those exposed through secondhand smoke, but also those exposed through thirdhand smoke. To prevent exposure to toxic tobacco smoke and its residue, they support 100% tobacco-free environments.

Thirdhand Smoke Researcher Presents at AAAS
In September, Dr. Hugo Destaillats, Staff Scientist at Lawrence Berkeley National Laboratory and a member of the Thirdhand Smoke Research Consortium, addressed the American Association for the Advancement of Science. He discussed thirdhand smoke chemicals and their health effects.

Recent Immigrants Find Their Mall is Not Just for Shopping
In an effort to educate new immigrants and refugees in their community about the dangers of cigarettes, e-cigarettes, and hookah, these women take their message to the local mall and other businesses in Minneapolis. These product not only harm their users, but also their families, friends, and pets through secondhand smoke and toxic thirdhand smoke residue.

University of Texas at El Paso and University of California, Riverside Researchers Collaborate to Investigate Thirdhand Smoke and Heart Disease
University of Texas at El Paso’s School of Pharmacy was awarded $1.8 million to study thirdhand smoke and cardiovascular disease. Their research will focus on the chemicals in thirdhand smoke, their increasing toxicity over time, and their effect on cardiovascular diseases such as heart attacks and strokes.

University of California, Irvine, Researchers Show Hookah Smoke Contains Toxic Chemicals
Hookah smoke contains many of the same toxic chemicals as regular cigarettes. But because more smoke is inhaled with each puff on a hookah pipe, and hookah smoking sessions tend to be longer, hookah smoke delivers more toxic chemicals to the smoker than a regular cigarette. Like smoke from regular cigarettes, smoke from hookah is a precursor to thirdhand smoke leaving behind toxic residue on clothes and indoor environments.

New CDC Report Shows Large Numbers of Non-Smoking US Children are Exposed to Tobacco Pollution
More than 1/3 of US children ages 3-17 are exposed to secondhand smoke, the precursor of thirdhand smoke. Children who are exposed to secondhand smoke inside homes or cars are also exposed to thirdhand smoke, the toxic residue that remains in indoor environments where tobacco has been smoked.