- "Third-hand Smoke" means the chemical residual of tobacco smoke contamination that clings to clothing, wall, furniture, carpet, cushions, hair, skin and other materials after the cigarette is extinguished.
- Nicotine residues will soak into a smoker’s skin and clothing even if they smoke outside. These toxic residues follow the smoker back indoors and get spread everywhere.
- Tobacco toxins can persist on the surface of objects for weeks and even months after nicotine vapor has been absorbed. Ventilating a room by using fans or opening windows is not sufficient to rid the third-hand smoke.
- Cigarette smoke contains up to 7,000 chemicals, of which hundreds are harmful and about 70 can cause cancers. Though the actual time required for the toxins to vanish from fabric and wall is still unknown, it is believed that the saturated toxics do not literally disappear in a short period of time.
- Toxic substances in third-hand smoke are as follows: hydrocyanic acid, used in chemical weapons; butane, which is used in lighter fluid; toluene, found in paint thinners; arsenic; lead; carbon monoxide; and even polonium-210, which is highly radioactive carcinogen.
What is "Third-hand Smoke"?
Risk Associated to Children
Infants and children are at highest risk than adults as they have closer exposure to tobacco deposits on surfaces of furniture and clothing. As they crawl and play around, they tend to touch and sometimes swallow those dangerous particles, allowing the harmful chemicals to enter their bodies.
- Tobacco particulates have been associated with cognitive deficits among children. The higher tobacco exposure level, the higher risk of getting reading deficits.
- Studies underscored third-hand smoke could affect reading ability of infants and their risk of getting lung cancer increased by 25% with co-living smokers.
- Recently scientists have linked third-hand smoke to pulmonary & respiratory diseases of infants, as well as increasing chance of getting asthma and otitis media (middle ear infection), and resulting in poor physique as well.
- A study published in the Proceedings of the National Academy of Sciences (PNAS) ,authored by researchers with the Lawrence Berkeley National Laboratory, reveals that nicotine could react with nitrous acid (a common air pollutant, mainly produced from gas appliances and motor vehicle emissions) to produce carcinogenic tobacco-specific nitrosamines (TSNAs).
- Human exposure to TSNAs either by dust inhalation or direct contact of skin. Therefore, TSNAs pose the greatest hazard to crawling infants and toddlers.
Studies of "Third-hand Smoke"
The first study on health effects of third-hand smoke and household smoking bans was led by Professor Jonathan P. Winickoff, from the Medical School of Massachusetts General Hospital for Children. In the study, researchers surveyed 1,478 household on their opinions on smoking:
- 95.4% of nonsmokers and 84.1% of smokers agreed that second-hand smoke and tobacco smoke cause harms to children’s health
- Only 65.2% of nonsmokers and 43.3% of smokers agreed that third-hand smoke brings the same harmful effect to children
- Only 3.4% of interviewees were not clear about the threats on children’s health by second-hand smoke, but 22% of interviewees did not know the hazards of third-hand smoke on children
- The result demonstrated public’s unawareness towards third-hand smoke.
Reduction on "Third-hand Smoke"
- Growing number of countries are enforcing smoking bans in restaurants, pubs and workplaces, aiming at protecting workers’ health. Yet legislation on household smoking bans has not been stressed. Prolonged exposure to second-hand and third-hand smoke in household would seriously affect the health of nonsmokers, especially children.
- Most adults are aware of the fact that second-hand smoke could harm their health. Therefore, they would take actions like ventilating a room while smoking, outdoor smoking or return home until the cigarette smell is vanished. However, they are not aware of the toxic substances already cling to their clothing. It reflected their lack of knowledge on hazards of third-hand smoke.
- There is no safe level of exposure to tobacco smoke. Quit smoking for the sake of yourself, and help your family to avoid all harms from smoking. Smokers should quit smoking and avoid smoking in household.
- Increase smokers and parents’ awareness of how third-hand smoke harms the health of children could encourage smoking bans at home.
- Government should raise the public awareness on third-hand smoking and emphasize its hazards on the health of children, though education, medical services and legislations.
Source：Jonathan P. Winickoff, Joan Friebely, Susanne E. Tanski, Cheryl Sherrod, Georg E. Matt, Melbourne F. Hovell and Robert C. McMillen. Beliefs About the Health Effects of “Thirdhand” Smoke and Home Smoking Bans. Pediatrics 2009;123;e74-e79