The Dangers of Third Hand Smoke

Health Professional, Medical Reviewer

Even when a smoker has stopped puffing away, the furniture nearby may still be.

Studies show that these residual chemicals, byproducts of cigarette smoke, can cling to hair, skin, clothes, furniture, drapes, walls, and carpets. They linger long after the smoker has left the area. Residue can also linger on interior car surfaces. This can also be a problem in hotels that allow smoking on some floors. The residue also typically builds up on these surfaces over time.

A large study of more than 95,000 cases presented at the Pediatric Academic Societies in 2016 shows that a quarter of American children lived with smokers, and these children had significantly higher doctor and hospital visits, as well as increased rates of infections, asthma flare-ups and other respiratory events, compared to children living in households with no smokers.

Exposure to secondhand smoke is harmful to non-smokers. The effect of secondhand smoke is far more dramatic in children, because their respiratory system is still developing.

Specific data from the research abstract, "Tobacco Smoke Exposure and Health Care Utilization among Children Nationwide,” also reveal that about 5 percent of the children lived with someone who actually smoked inside the home. Overall, a child living with a smoker or with exposure to smoke in the home was much more likely to need medical care visits and sick care. The children were also less likely to have dental care visits.

Responsible parents may take some precautions, such as smoking in different rooms of the house away from the child, or waiting until children are out of the house to smoke, or aerating the rooms so that the children will not have the direct effect of the cigarette smoke. This is certainly better than smoking in a room where the child is also present. But is this enough to limit or prevent health consequences?

What is third-hand smoke?Exposure to tobacco doesn’t just mean being in the direct presence of a smoker or being in an environment right after someone has smoked. There is also a phenomenon called third-hand smoke. Third-hand smoke is exposure to the residuals of nicotine and other chemicals left on surfaces by smoke.

This thirdhand smoke residue resists normal cleaning and cannot be eliminated simply by airing rooms, opening windows, vacuuming, or using fans.

What kind of danger does this chemical residue pose?

Many studies assess Environmental Tobacco Smoke (ETS) in this third-hand residual form. It appears that the danger posed is actually from the transformation that takes place once the residue is present. The residue from nicotine and its breakdown products can recombine and form carcinogens called nitrosamines.

Some of this information comes from studies conducted but never published by the Phillip Morris Company. Internal tobacco industry documents available at the University of California in San Francisco suggest that the conversion to nitrosamines takes place two hours after the burning of tobacco has ceased. The cigarette industry knew this between 1983 and 1997.

What are nitrosamines?

You may have heard about these carcinogenic compounds in relation to burning meat or cured meats. Nitrosamines are chemical compounds formed by a reaction between foods (typically proteins) and a nitrosating agent often during a heating or drying process. They can also form from residuals of tobacco like e-cigarette vapor, and also from the residue left by cigarette smoke.

How long does the residue from tobacco stay in the environment?

One study involved ten cigarettes smoked by machines for six out of seven days, over a four-week period, in a carpeted area measuring about 50 cubic meters.

Experts than studied concentrations of Environmental Tobacco Smoke (ETS), along with specific tracer measurements for toxic compounds including naphthalene and arsenic. The findings reveal significant amounts of toxic by-products were emitted for weeks after the smoking ended. Researchers also noted that these dangerous residues can emit compounds back into the air under certain conditions.

The key point is that the more furniture, drapes and other solid elements present (providing large surface areas) the more sources there are for the noxious exposures. Lower socioeconomic conditions may mean small rooms crowded with furniture and surfaces ripe for these noxious residues. In a household with a smoker or smokers, that translates to high third-hand smoke exposures for children.

What you need to know about third-hand smoke

There are no safe measures to protect children from environmental tobacco smoke. Secondhand and third-hand smoke offer grave dangers to children. The only way to protect children is to avoid smoking at all in any environments where children live and breathe.

See More Helpful Articles:

Second-hand Smoke is a Danger to Kids

You Can Quit Smoking - Here's How

Asthma: What Causes Exacerbations and What Can Help?

Eli Hendel, M.D. is a board-certified Internist and pulmonary specialist with board certification in Sleep Medicine. He is an Assistant Clinical Professor of Medicine at Keck-University of Southern California School of Medicine, Qualified Medical Examiner for the State of California Department of Industrial Relations, and Director of Intensive Care Services at Glendale Memorial Hospital. His areas of expertise in private practice include asthma, COPD, sleep disorders, obstructive sleep apnea, and occupational lung diseases.