You may never have heard of thirdhand smoke, yet there are chances that you have smelled it. The Thirdhand smoke (THS), which is a toxic brew of gases and particles clinging to smokers’ hair and clothing is invisible. It remains with cushions and carpeting that lingers long after secondhand smoke has cleared from a room.First part of this article was published last Saturday March 12, 2011 [http://www.dailynews.lk/2011/03/12/fea01.asp]
“Our study shows that when this residual nicotine reacts with ambient nitrous acid, it forms carcinogenic tobacco-specific nitrosamines or TSNAs,” Destaillats said. “TSNAs are among the most broadly acting and potent carcinogens present in unburned tobacco and tobacco smoke.”
Read moreThe researchers used cellulose as a model of indoor material and exposed it to cigarette smoke. They then exposed it to a “high, but reasonable” concentration of nitrous acid for three hours. The levels of newly formed TSNAs were 10 times higher after the nitrous acid exposure. The TSNAs also formed quickly, the researchers found.
“Given the rapid absorption and persistence of high levels of nicotine on indoor surfaces, including clothing and human skin, our findings indicate that THS represents an unappreciated health hazard through dermal exposure, dust inhalation and ingestion,” said lead author Mohamad Sleiman, also of Berkeley Lab.
[THS] |
* Toxic brew of gases, particles * Cling to hair, clothing of smokers * Residual contamination from tobacco smoke * Term used by Prof Janathan Winickoff in 2009 * Poses greatest hazard to infants * Substances contained are hydrogen cyanide, arsenic etc |
Smoking indoors
Since most vehicle engines emit some nitrous acid that can infiltrate the passenger compartments, tests were also conducted on surfaces inside the truck of a heavy smoker, including the surface of a stainless steel glove compartment. These measurements also showed substantial levels of TSNAs.
Individuals are most likely exposed to these TSNAs through either inhalation of dust or the contact of skin with carpet or clothes, suggesting THS might pose the greatest hazard to infants and toddlers.
“Smoking outside is better than smoking indoors, but nicotine residues will stick to a smoker’s skin and clothing,” said study co-author Lara Gundel also of Berkeley Laboratory. “Those residues follow a smoker back inside and get spread everywhere.”
“What we see in this study is that the reactions of residual nicotine with nitrous acid at surface interfaces are a potential cancer hazard and these results may be just the tip of the iceberg,” said Kamlesh Asotra of the University of California’s Tobacco-Related Disease Research Program, which funded this study.
Tobacco toxins
In their paper, the authors suggest several ways to limit the impact of THS, including the implementation of 100 percent smoke-free environments, public places and self-restrictions in residences and automobiles. In building where high levels of smoking has occurred, replacing furnishings, carpets and wallboard could reduce exposures.
“Everyone knows that second-hand smoke is bad, but they don’t know about THS,” said Dr Jonathan P Winickoff, the lead author of the study and an assistant professor of paediatrics at Harvard Medical School.
“When their children are out of the house, they might smoke. Or they smoke in the car. Or they strap the child in the car seat in the back and crack the window and smoke and they think it’s okay because the second-hand smoke isn’t getting to their children,” Dr Winickoff continued. “We needed a term to describe these tobacco toxins that aren’t visible.”
Winickoff is concerned that small children might be particularly exposed and more susceptible to toxicants in THS. “Infants crawl over, touch and mouth contaminated surfaces and are known to consume up to a quarter gram per day of dust-twice as much as do adults,” he says. “They could therefore be getting much higher doses of THS toxicants than older children and adults.” Gundel also suggests that cleaning staff working in hotels where smoking is allowed could receive high THS exposures, for example by handling THS-contaminated bedding.
Focus group
THS is what one smells when a smoker gets in an elevator after going outside for a cigarette, he said, or in a hotel room where people were smoking “Your nose isn’t lying,” he said. “The stuff is so toxic that your brain is telling you: ‘Get away.’”
The study reported on attitudes toward smoking in 1,500 households across the United States. It found that the vast majority of both smokers and nonsmokers were aware that second-hand smoke is harmful to children. Some 95 percent of nonsmokers and 84 percent of smokers agreed with the statement that “inhaling smoke from a parent’s cigarette can harm the health of infants and children.”
But far fewer of those surveyed were aware of the risks of THS. Since the term is so new, the researchers asked people if they agreed with the statement that “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 agreed with that statement, which researchers interpreted as acknowledgement of the risks of THS. The belief that second-hand smoke harms children’s health was not independently associated with strict smoking bans in homes and cars, the researchers found. On the other hand, the belief that THS was harmful greatly increased the likelihood the respondent also would enforce a strict smoking ban at home, Dr Winickoff said.
“That tells us we’re onto an important new health message here,” he said. “What we heard in focus group after focus group was, ‘I turn on the fan and the smoke disappears.’ It made us realize how many people think about second-hand smoke, they’re telling us they know it’s bad but they’ve figured out a way to do it.”
Telephone survey
The data was collected in a national random-digit-dial telephone survey done between September and November 2005. The sample was weighted by race and gender, based on census information. Dr Philip Landrigan, a paediatrician who heads the Children’s Environmental Health Centre at Mount Sinai School of Medicine in New York, said the phrase THS is a brand, new term that has implications for behaviour.
Research findings
“The central message here is that simply closing the kitchen door to take a smoke is not protecting children from the effects of that smoke,” he said. “There are carcinogens in this THS and they are a cancer risk for anybody of any age who comes into contact with them.”
Among the substances in THS are hydrogen cyanide, used in chemical weapons; butane, which is used in lighter fluid influence, found in paint thinners; arsenic; lead; carbon monoxide polonium-210, the highly radioactive carcinogen that was used to murder former Russian spy Alexander V Litvinenko that eleven of the compounds are highly carcinogenic.
The Science Daily (January 12, 2011) - Scientists are reporting that so-called ‘THS’, the invisible remains of cigarette smoke that deposits on carpeting, clothing, furniture and other surfaces, may be even more of a health hazard than previously believed. The study, published in ACS’ journal, Environmental Science & Technology, extends the known health risks of tobacco among people who do not smoke, but encounter the smoke exhaled by smokers or released by smoldering cigarette butts.
Studies show that nicotine in THS can react with the ozone in indoor air and surfaces like clothing and furniture, to form other pollutants. Exposure to them can occur to babies crawling on the carpet, people napping on the sofa, or people eating food tainted by THS. A smoke-related chemical residue, referred to as THS hang around for months after a smoker has left, reveals the research findings. In an effort to learn more about THS, the scientists studied interactions between nicotine and indoor air on a variety of different materials, including cellulose (a component of wood furniture), cotton, and paper to simulate typical indoor surfaces. They found that nicotine interacts with ozone, in indoor air, to form potentially toxic pollutants on these surfaces. “Given the toxicity of some of the identified products and that small particles may contribute to adverse health effects, the present study indicates that exposure to THS may pose additional health risks,” the article notes.
Courtesy - Daily News by Manjari PEIRIS
