Thirdhand Smoke
We know that smoking and secondhand smoke exposure are harmful, but what about "thirdhand smoke"? This is a relatively new term used to describe the residual contamination from tobacco smoke that lingers in rooms long after smoking stops and remains on our clothes after we leave a smoky place. It may seem merely like an offensive smell, but it is also indicative of the presence of tobacco toxins.
Thirdhand smoke consists of the tobacco residue from cigarettes, cigars, and other tobacco products that is left behind after smoking and builds up on surfaces and furnishings. Tobacco smoke is composed of numerous types of gasses and particulate matter, including carcinogens and heavy metals, like arsenic, lead, and cyanide. Sticky, highly toxic particulates, like nicotine, can cling to walls and ceilings. Gases can be absorbed into carpets, draperies, and other upholsteries. A 2002 study found that these toxic brews can then reemit back into the air and recombine to form harmful compounds that remain at high levels long after smoking has stopped occurring.
There is a growing body of evidence that this lingering tobacco residue has significant health risks. People, especially children and hospitality industry workers, can have considerable exposure to it. As confirmed by the 2006 Surgeon General's Report, there is no safe level of exposure to tobacco smoke. And tobacco smoke toxins remain harmful even when breathed or ingested after the active smoking ends.
A study published in February 2010 found that thirdhand smoke causes the formation of carcinogens. The nicotine in tobacco smoke reacts with nitrous acid - a common component of indoor air - to form the hazardous carcinogens. Nicotine remains on surfaces for days and weeks, so the carcinogens continue to be created over time, which are then inhaled, absorbed or ingested.
Children of smokers are especially at risk of thirdhand smoke exposure and contamination because tobacco residue is noticeably present in dust throughout places where smoking has occurred. The homes, hair, clothes, and cars of smokers can have significant levels of thirdhand smoke contamination. Young children are particularly vulnerable, because they can ingest tobacco residue by putting their hands in their mouths after touching contaminated surfaces.
Awareness about thirdhand smoke is increasing, and it gained a great deal of attention in January 2009 when the journal Pediatrics published a study assessing people's beliefs about the health effects of thirdhand smoke and children's level of exposure to it. However, the report found there is much less awareness about thirdhand smoke exposure and its harm to children than there is awareness about the dangers of secondhand smoke.
The growing understanding of thirdhand smoke contamination reaffirms the need for more smokefree places and for avoiding exemptions in smokefree laws that permit smoking at private events in public places or in businesses during late evening hours; these kinds of provisions do not protect people's health.
Parents, landlords, business owners and others need to be aware of the health risks of exposure to thirdhand smoke and recognize that eliminating smoking is the only way to protect against tobacco's smoke contamination.
Even after secondhand smoke has cleared, cigarettes leave some of their toxic residue behind. Discover how University of California researchers at California's Thirdhand Smoke Consortium are investigating the problem:
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Research Studies
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Thirdhand
smoke, a big health hazard Studies
find that toxicity caused by second-hand smoke remains long after a
smoker leaves the premises Snuffing
'third-hand' smoke; Stratford Health Department sparks ... The
dangers of third hand smoke Third-Hand
Smoke - A New Hazard To Be Aware Of Clearing
the Air of Thirdhand Smoke - UCTV Prime Cuts Even
Thirdhand Smoke Is Dangerous Scientists:
Third Hand Smoke Also a Danger Invisible
health villain for children: Thirdhand smoke As reported in the journal Pediatrics ("Beliefs about the Health
Effects of Thirdhand Smoke and Home Smoking Bans," 2009), 95.4
percent of nonsmokers and ... VIDEO:
Dangers of third-hand smoke Venkat Murphy knows firsthand the health hazards of cigarette smoke.
Just smelling it on someone's clothes or in a room can trigger an asthma
attack. ... Third-hand
threats: Nicotine and nitrosamines found in dust in homes of smokers
and non-smokers Study:
Third-hand smoke can endanger unborn babies 'Thirdhand
smoke' leaves long-lasting toxins Study
Finds Thirdhand Smoke Poses Danger To Unborn Babies' Lungs Stepping outside to smoke a cigarette may not be enough to protect the lungs and life of a pregnant woman's unborn child, according to a new study in the American Journal of Physiology. The study, by researchers at the Los Angeles Biomedical Research Institute (LA BioMed), found prenatal exposure to toxic components of a newly recognized category of tobacco smoke--known as thirdhand smoke--can have as serious or an even more negative impact on an infants' lung development as postnatal or childhood exposure to smoke. Thirdhand smoke is the newly formed toxins from tobacco smoke that remain on furniture, in cars, on clothing and on other surfaces--long after smokers have finished their cigarettes. "Thirdhand smoke is a stealth toxin because it lingers on the
surfaces in the homes, hotel rooms, casinos and cars used by smokers
where children, the elderly and other vulnerable people may be exposed
to the toxicants without realizing the dangers," said Virender
Rehan, MD, a principal investigator at LA BioMed and corresponding author
of the study. "Pregnant women should avoid homes and other places
where thirdhand smoke is likely to be found to protect their unborn
children against the potential damage these toxins can cause to the
developing infants' lungs. ... Babies
who sleep with smoker parents exhibit high nicotine levels VIDEO:
The Hidden Danger of Third-Hand Smoke (03:15) Getting
it thirdhand It’s common knowledge that smoking is bad for smokers. That’d be firsthand smoke. It’s also generally acknowledged that it’s harmful for nonsmokers to be around somebody smoking. That’s secondhand smoke. Now comes thirdhand smoke: the gases, particles and nicotine left on clothes, hair, and lingering in the air long after the smoker has crushed the cigarette. It, too, may be bad for us. Environmental Health Perspectives describes how, in 1991, researchers found nicotine in the dust of smokers’ homes. Not surprising. Then, in 2004, they found it in the dust of people’s homes when no one had smoked there for three months. There was more of it in places like the living room, far less in places like an infant’s room, where parents didn’t smoke. But even when residents took their smoking outside, traces of nicotine could be found in the house. The only place nicotine wasn’t found in the dust was in homes where no one had ever smoked. A 2008 study found similar results in cars, where even a year-long smoking ban in a car in which cigarettes were formerly smoked was not enough to rid it of nicotine. Now, researchers find that thirdhand smoke (THS) lingers after smokers
move out of their homes, “even after being vacant for two months
and being prepared for new residents, sometimes with new carpeting and
paint,” the study describes ... Third-hand
smoke is dangerous, especially for crawling babies The hazardous effects of cigarette smoking on the human body are well known. Even it is well documented that longtime exposure to secondhand smoke can harm human health in many ways. The invisible remains of cigarette smoke that deposit on carpeting, clothing, furniture, and other surfaces are called third-hand smoking. Third-hand smoke poses health risk The study, which was conducted at the Israel Institute of Technology, suggests that residues from cigarette smoke that linger on fabrics, papers, carpets, and other surfaces pose a larger health hazard than previously understood. Published in the journal Environmental Science & Technology, the study findings suggest that the so-called third-hand smoke augments the risk of respiratory illnesses among non-smokers. Study details The researchers found that the nicotine interacting with ozone, in
indoor air and other surfaces, creates even more health hazards from
third-hand smoke than previously believed, especially for young children
who are more likely to be crawling on floors and carpets and place objects
in their mouth. ... 'Thirdhand
Smoke' a Lingering Problem A new study found the chemical by-products of tobacco smoke cling to the air and surfaces of smokers' homes long after they've moved out, msnbc.com reported Dec. 16. Researchers at San Diego State University led by psychology professor Georg Matt, Ph.D., analyzed the homes of 100 smokers and 50 nonsmokers for chemical smoking residue just before the residents completed a planned move. Two months later, they re-measured air and surface nicotine in the homes that had been rented or sold to nonsmokers, and checked the fingerprints of the new residents for nicotine. They also analyzed urine samples of the youngest new inhabitants for cotinine, a nicotine metabolite. Although the homes had been thoroughly cleaned, including painting and carpet replacement in many cases, nonsmokers living in the homes of former smokers had seven to eight times more nicotine on their fingertips than those who moved into nonsmoker homes, and urine cotinine levels were three to five times higher in their children. Overall, air and surface nicotine was 30 to 150 times higher in the homes formerly occupied by smokers compared with homes formerly occupied by nonsmokers. Smoke-related chemical residues, referred to as thirdhand smoke, "hang around for months after a smoker has left," said Matt. "While there was considerably less in homes once an active smoker moved out, there was still 10 to 20 percent of what was found while the smoker still lived there." Such homes are "reservoirs of tobacco smoke pollutants,"
creating a source for involuntary tobacco exposure to those who move
into them, the authors said. ... Another
reason to quit smoking: third-hand smoke Tobacco smoke has added a new potential danger to its list of hazards: third-hand smoke. The term was coined in a study published in the medical journal, “Pediatrics,” to describe the interaction of tobacco smoke with indoor surfaces. Most people know that first-hand smoke is inhaled directly by a smoker and second-hand smoke is the smoke passively breathed in by people near someone smoking. Researchers have determined that third-hand smoke is the residue left on surfaces from second-hand smoke. The pungent scent of smoke that lingers in enclosed spaces long after a cigarette has been extinguished gives away the presence of third-hand smoke. Parents often smoke when their children are out of the house to try to reduce second-hand smoke exposure. They also turn on fans to ventilate the room and let down a window in a car to dissipate cigarette smoke. However, these actions do not eliminate the health hazards associated with tobacco smoke. A study published in the journal, “Tobacco Control,” found that the sticky residue from nicotine and tar can persist in carpets, furnishings, drapes, dust and on skin and clothes for several months after smoking had ceased. New research has shown that residual nicotine reacts with a common
air pollutant, nitrous acid, which is a combustion product generated
with the use of gas-powered appliances and vehicle engines. The nicotine
and nitrous acid combine to form more carcinogenic compounds. These
small particles can enter the body either through skin exposure, dust
inhalation or ingestion. ... Residual
tobacco smoke in used cars: futile efforts and persistent pollutants
Methods: Surface wipe, air, and dust samples were collected in used cars sold by nonsmokers (n = 40) and smokers (n = 87) and analyzed for nicotine. . . . Discussion: Findings suggest that smokers can prevent their cars from becoming contaminated with residual TSP by reducing or ceasing smoking; however, commonly used cleaning and ventilation methods did not successfully decrease contamination levels. Disclosure requirements and smoke-free certifications could help protect buyers of used cars and empower them to request nonsmoking environments or a discount on cars that have been smoked in previously. … Determination
of Volatile Organic Compounds for a Systematic Evaluation of Third-hand
Smoking. Third-hand smoking was quantitatively evaluated with a polymer-packed sample preparation needle and subsequent gas chromatography–mass spectroscopy analysis. The extraction needle was prepared with polymeric particles as the extraction medium, and successful extraction of typical gaseous volatile organic compounds (VOCs) was accomplished with the extraction needle. For an evaluation of this new cigarette hazard, several types of clothing fabrics were exposed to sidestream smoke, and the smoking-related VOCs evaporated from the fabrics to the environmental air were preconcentrated with the extraction needle. Smoking-related VOCs in smokers’ breath were also measured using the extraction needle, and the effect of the breath VOCs on third-hand smoking pollution was evaluated. The results demonstrated that a trace amount of smoking-related VOCs was successfully determined by the proposed method. The adsorption and desorption behaviors of smoking-related VOCs were clearly different for each fabric material, and the time variations of these VOCs concentrations were quantitatively evaluated. The VOCs in the smokers’ breath were clearly higher than that of nonsmokers’; however, the results suggested that no significant effect of the smokers’ breath on the potential pollution occurred in the typical life space. The method was further applied to the determination of the actual third-hand smoking pollution in an automobile, and a future possibility of the proposed method to the analysis of trace amounts of VOCs in environmental air samples was suggested. Carcinogens
form from third-hand smoke Nicotine in third-hand smoke, the residue from tobacco smoke that clings to virtually all surfaces long after a cigarette has been extinguished, reacts with the common indoor air pollutant nitrous acid to produce dangerous carcinogens. This new potential health hazard was revealed in a multi-institutional study led by researchers with the Lawrence Berkeley National Laboratory (Berkeley Lab). "The burning of tobacco releases nicotine in the form of a vapor that adsorbs strongly onto indoor surfaces, such as walls, floors, carpeting, drapes and furniture. Nicotine can persist on those materials for days, weeks and even months. Our study shows that when this residual nicotine reacts with ambient nitrous acid it forms carcinogenic tobacco-specific nitrosamines or TSNAs," says Hugo Destaillats, a chemist with the Indoor Environment Department of Berkeley Lab's Environmental Energy Technologies Division. "TSNAs are among the most broadly acting and potent carcinogens present in unburned tobacco and tobacco smoke." Destaillats is the corresponding author of a paper published in the Proceedings of the National Academy of Sciences (PNAS). Co-authoring the PNAS paper with Destaillats were Mohamad Sleiman, Lara Gundel and Brett Singer, all with Berkeley Lab's Indoor Environment Department, plus James Pankow with Portland State University, and Peyton Jacob with the University of California, San Francisco. ... Formation
of carcinogens indoors by surface-mediated reactions of nicotine with
nitrous acid, leading to potential thirdhand smoke hazards A
New Cigarette Hazard - 'Third-Hand Smoke' Parents who smoke often open a window or turn on a fan to clear the air for their children, but experts now have identified a related threat to children's health that isn't as easy to get rid of: third-hand smoke. That's the term being used to describe the invisible yet toxic brew of gases and particles clinging to smokers' hair and clothing, not to mention cushions and carpeting that lingers long after second-hand smoke has cleared from a room. The residue includes heavy metals, carcinogens and even radioactive materials that young children can get on their hands and ingest, especially if they're crawling or playing on the floor. Doctors from MassGeneral Hospital for Children in Boston coined the term "third-hand smoke" to describe these chemicals in a new study that focused on the risks they pose to infants and children. The study was published in this month's issue of the journal Pediatrics… What
is third-hand smoke? Is it hazardous? Ever take a whiff of a smoker's hair and feel faint from the pungent scent of cigarette smoke? Or perhaps you have stepped into an elevator and wondered why it smells like someone has lit up when there is not a smoker in sight. Welcome to the world of third-hand smoke. "Third-hand smoke is tobacco smoke contamination that remains after the cigarette has been extinguished," says Jonathan Winickoff, a pediatrician at the Dana-Farber/Harvard Cancer Center in Boston and author of a study on the new phenomenon published in the journal Pediatrics. According to the study, a large number of people, particularly smokers, have no idea that third-hand smoke-the cocktail of toxins that linger in carpets, sofas, clothes and other materials hours or even days after a cigarette is put out-is a health hazard for infants and children. Of the 1,500 smokers and nonsmokers Winickoff surveyed, the vast majority agreed that second-hand smoke is dangerous. But when asked whether they agreed with the statement, "Breathing air in a room today where people smoked yesterday can harm the health of infants and children," only 65 percent of nonsmokers and 43 percent of smokers answered "yes." "Third-hand smoke," a term coined by Winickoff's research team, is a relatively new concept but one that has worried researchers and nonsmokers for several years. "The third-hand smoke idea-concern over that-has been around for a long time. It's only recently been given a name and studied," says Stanton Glantz, director of the Center for Tobacco Control Research and Education at the University of California, San Francisco. "The level of toxicity in cigarette smoke is just astronomical when compared to other environmental toxins [such as particles found in automobile exhaust]," he adds, but notes that he is not aware of any studies directly linking third-hand smoke to disease [as opposed to second-hand smoke, which has been associated with disease]. |
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Matt, G.E.; Fortmann, A.L.; Quintana, P.J.E.; Zakarian, J.M.; Romero, R.A.; Chatfield, D.A.; Hoh, E.; Hovell, M.F., "Towards smoke-free rental cars: an evaluation of voluntary smoking restrictions in California," Tobacco Control 22(3): 201-207, May 2013. |
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Hang, B.; Sarker, A.H.; Havel, C.; Saha, S.; Hazra, T.K.; Schick, S.; Jacob, P.; Rehan, V.K.; Chenna, A.; Sharan, D.; Sleiman, M.; Destaillats, H.; Gundel, L.A., "Thirdhand smoke causes DNA damage in human cells," Mutagenesis [Epub ahead of print], March 5, 2013. |
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Quintana, P.J.; Matt, G.E.; Chatfield, D.; Zakarian, J.M.; Fortmann, A.L.; Hoh, E., "Wipe sampling for nicotine as a marker of thirdhand tobacco smoke contamination on surfaces in homes, cars, and hotels," Nicotine and Tobacco Research [Epub ahead of print], March 4, 2013. |
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Drehmer, J.E.; Ossip, D.J.; Rigotti, N.A.; Nabi-Burza, E.; Woo, H.; Wasserman, R.C.; Chang, Y.; Winickoff, J.P., "Pediatrician interventions and thirdhand smoke beliefs of parents," American Journal of Preventive Medicine 43(5): 533-536, November 2012. |
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Hood, N.E.; Ferketich, A.K.; Klein, E.G.; Pirie, P.; Wewers, M.E., “Associations between self-reported in-home smoking behaviours and surface nicotine concentrations in multiunit subsidised housing,” Tobacco Control [Epub ahead of print], October 23, 2012. |
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Fleming, T.; Anderson, C.; Amin, S.; Ashley, J., "Third-hand tobacco smoke: significant vector for PAH exposure or non-issue?", Integrated Environmental Assessment and Management 8(4): 763-764, October 2012. |
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Hoh, E.; Hunt, R.N.; Quintana, P.J.E.; Zakarian, J.M.; Chatfield, D.A.; Wittry, B.C.; Rodriguez, E.; Matt, G.E., "Environmental tobacco smoke as a source of polycyclic aromatic hydrocarbons in settled household dust," Environmental Science & Technology 46(3): 4174 - 4183, April 3, 2012. |
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Matt, G.E.; Fortmann, A.L.; Quintana, P.J.; Zakarian, J.M.; Romero, R.A.; Chatfield, D.A.; Hoh, E.; Hovell, M.F., "Towards smoke-free rental cars: an evaluation of voluntary smoking restrictions in California," Tobacco Control [Epub ahead of print], February 15, 2012. |
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Jung, J.W.; Ju, Y.S.; Kang, H.R., "Association between parental smoking behavior and children's respiratory morbidity: 5-year study in an urban city of South Korea," Pediatriac Pulmonology [Epub ahead of print], October 17, 2011. |
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Tillett, T., "Thirdhand smoke in review: research needs and recommendations," Environmental Health Perspectives 11(9): A399, September 2011. |
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Matt, G.E.; Quintana, P.J.E.; Destaillats, H.; Gundel, L.A.; Sleiman, M.; Singer, B.C.; Jacob III, P.; Benowitz, N.; Winickoff, J.P.; Rehan, V.; Samet, J.; Wang, Y.; Hang, B.; Martins-Green, M.; Pankow, F.J.; Hovell, M.F.; Talbot, P.; Schick, S., "Thirdhand tobacco smoke: emerging evidence and arguments for a multidisciplinary research agenda," Environmental Health Perspectives [Epub ahead of print], May 31, 2011. |
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Rehan, V.K.; Sakurai, R.; Torday, J.S., "Thirdhand smoke: a new dimension to the effects of cigarette smoke on the developing lung," American Journal of Physiology Lung Cellular and Molecular Physiology [Epub ahead of print], April 8, 2011. |
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Thomas, J.L.; Guo, H.; Carmella, S.G.; Balbo, S.; Han, S.; Davis, A.; Yoder, A.; Murphy, S.E.; An, L.C.; Ahluwalia, J.S.; Hecht, S.S., "Metabolites of a tobacco-specific lung carcinogen in children exposed to secondhand or thirdhand tobacco smoke in their homes," Cancer, Epidemiology, Biomarkers & Prevention [Epub ahead of print], April 5, 2011. |
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Burton, A., "Does
the smoke ever really clear? Thirdhand smoke exposure raises new concerns,"
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Schick, S., "Thirdhand smoke: here to stay," Tobacco Control 20(1): 1-3, January 2011. |
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Matt, G.; Quintana, P.J.E.; Zakarian, J.M.; Fortmann, A.L.; Chatfield, D.A.; Hoh, E.; Uribe, A.M.; Hovell, M.F., "When smokers move out and non-smokers move in: residential thirdhand smoke pollution and exposure," Tobacco Control 20(1): e1, January 2011. |
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Kuschner, W.G.; Reddy, S.; Mehrotra, N.; Paintal, H.S., "Electronic cigarettes and thirdhand tobacco smoke: two emerging health care challenges for the primary care provider," International Journal of General Medicine 4: 115-120, 2011. |
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Petrick, L.M.; Svidovsky, A.; Dubowski, Y., "Thirdhand smoke: heterogeneous oxidation of nicotine and secondary aerosol formation in the indoor environment," Environmental Science & Technology 45 (1): 328-333, 2011. |
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