Third-hand smoke is everywhere

When you walk into a private room in a hotel, you may feel dizzy or nauseous. You may think that the room is airtight, lacks fresh air, or has poor lighting. In fact, there is another more important and less noticeable invisible killer, which is third-hand smoke[1]. Third-hand smoke refers to the tobacco residue left on clothes, walls, carpets, furniture, and even hair and skin after smokers smoke. The toxic ingredients include hydrocyanic acid, butane, toluene, arsenic, lead, carbon monoxide, and 11 other highly carcinogenic compounds[2].

(Picture from Sohu.com)

01. Characteristics of third-hand smoke:

Common household fabrics, such as curtains, carpets, bed sheets, tablecloths, towels, etc., will have third-hand smoke residues. Compared with second-hand smoke, third-hand smoke remains for a longer time. The human body may be exposed to third-hand smoke through inhalation through the respiratory tract, absorption through the digestive tract, and skin contact. Third-hand smoke will adhere to any object it touches and accumulate over time, even penetrating into floors and walls, making it difficult to remove completely [3]. According to Fox News, third-hand smoke can last for at least 200 days indoors. The cumulative effect of third-hand smoke is quite obvious, and its toxicity increases over time. Even cleaning the room and repainting the walls is unlikely to completely solve the problem of third-hand smoke. Smoking in a confined space may also react with other pollutants in the space to form a toxic mixture.

02. Harms of third-hand smoke :

1. Thirdhand smoke can easily infect the human respiratory tract. Cigarettes contain formaldehyde, acetaldehyde, acrolein and other toxic substances. Once inhaled, they will damage the ciliary tissue of the respiratory system of the inhaler, weakening the function of the ciliary tissue to protect the respiratory system and remove foreign matter from the outside, causing toxic substances to enter the lungs smoothly and damage lung tissue. Infants and young children have a higher respiratory rate than adults, so they inhale more toxic substances than adults, which can easily cause respiratory diseases such as colds, asthma, pneumonia, and acute bronchitis [4].

2. Thirdhand smoke can cause a variety of diseases. Thirdhand smoke contains a variety of highly carcinogenic compounds. After entering the human body, some of these toxic substances can further enter cells and react with nucleic acids in the cell nucleus, causing gene chain breaks or base oxidation, which in turn causes gene mutations, leading to cancer and other diseases [4].

3. Thirdhand smoke can cause damage to multiple organs. Nicotine in cigarettes can damage the human immune system, nervous system, and circulatory system. Infants and young children, in particular, have an underdeveloped immune system and are less able to resist toxic substances. Inhaling thirdhand smoke can increase the risk of illness. Studies have shown that placing curtains and carpets that have been exposed to cigarette smoke in mouse cages resulted in 50% more inflammatory molecules in the blood and liver of mice compared to the control group after one month; cell damage to the liver and brain occurred after two months; and cortisol levels were 45% higher than the control group after four months, while fasting blood sugar and insulin levels were 30% higher. This means that thirdhand smoke not only damages the liver and lungs, but also increases the risk of diabetes, and the longer the exposure, the greater the harm[5].

(Picture from People's Daily Weibo)

03. How to prevent third-hand smoke :

The most direct and effective way to prevent third-hand smoke is for smokers to quit smoking as soon as possible, especially smoking should be completely banned at home.

(1) After smoking, smokers should change their clothes in time to remove the harmful substances absorbed;

(2) Curtains, wallpaper and other places in the home that are prone to absorbing harmful substances should be cleaned and replaced frequently;

(3) Try to avoid contact with smokers, as contact between people will inevitably lead to secondhand smoke or thirdhand smoke, which will cause irreversible damage to the body;

(4) Purify the air by using air purifiers or other methods to minimize the harm of third-hand smoke.

(5) There are also some small ways to eliminate the residue of third-hand smoke in daily life. For example, put the tea dregs after drinking them into a breathable cotton bag and place it in every corner of the room to absorb harmful substances;

(Photo from The Paper)

Copywriter: Shi Yuexin and Wang Donglei

Chinese Society of Toxicology

Baotou Medical College School of Public Health

References:

[1] Yang Kun. Seeing clearly the “third-hand smoke”[J]. Anti-cancer, 2016, 29(1): 40-44.

[2] Luo Dan. Thirdhand smoke is more carcinogenic[J]. New Knowledge, 2009(03):110-113.

[3] What is third-hand smoke? [J]. Shanghai Preventive Medicine, 2020, 32(06): 515.

[4] Tao Ling, Li Fawo, Zhang Pingying, et al. Health hazards of third-hand smoke and tobacco control strategies[J]. Chinese Journal of Health Care and Nutrition, 2015, 25(15): 325.

[5] “Thirdhand smoke” is damaging your internal organs[J]. Big Data Era, 2017, (06): 75.

[6] Zhang Weiyin, Cao Huanlu, Wang Shunde. Beware of the invisible killer: third-hand smoke[J]. Life and Disasters, 2011, (07): 26-27.

[7] Tao Ling, Su Fawo, Wang Yanhua, Zhang Pingying. Third-hand smoke exposure of infants and young children in the home and the status of smoking ban in the home[J]. Chinese Journal of Clinical New Medicine, 2017, 10(06): 586-588.