“Thirdhand smoke” (THS) refers to residues of nicotine and other harmful chemicals from tobacco smoke that absorb into indoor surfaces, furniture, carpets, bedsheets, skin, and pet fur.
THS residue can contain more than 250 chemicals and remain on surfaces for weeks, months, or even years. These chemicals may also re-emit back into the air as gases and react with other chemicals, creating new chemicals that may be harmful to inhale.
Children are particularly susceptible to THS because they spend more time on the floor and often touch surfaces and objects with their hands or mouth.
In this article, we will discuss what THS is, its potential impacts on health, how to prevent it, and when a person should speak with a doctor.
The residue can stay on surfaces for weeks, months, or even years. It can build up on skin, animal fur, and indoor surfaces such as:
- car dashboards
THS residue can also re-emit back into the air and react with other chemicals in the environment, forming new chemicals that can cause harm when people inhale them. The longer these chemicals are in the air, the
There is limited research into the effects of THS on people. However, a 2014 study on mice suggested that THS
Research from 2021 suggests that exposure to any kind of tobacco smoke, including THS,
If a pregnant person lives with someone who smokes, they should encourage that person to quit smoking as soon as possible. Similarly, if a pregnant person smokes, they should try to quit smoking right away, as smoking while pregnant may:
- cause the infant to be born early
- damage the infant’s lungs and brain
- slow the infant’s growth before birth
- raise the infant’s risk of developing congenital anomalies
doublethe person’s risk of abnormal bleeding during pregnancy and labor
- increase the risk of sudden infant death syndrome
Children are more vulnerable to THS because they often touch surfaces and objects in the home with their hands or mouths.
Research suggests that children also have thinner skin and breathe faster than adults, which can
Studies suggest that THS may have several negative health effects in adults,
- changes and damage to DNA, which can lead to the formation of cancerous cells
- problems with wound healing
- an increased risk of lung fibrosis
- liver damage
- metabolic syndrome, which may increase a person’s likelihood of developing conditions such as type 2 diabetes, high blood pressure, coronary artery disease, obesity, and stroke
However, researchers advise that further studies are necessary to investigate the effects of THS on human health.
The only way to prevent THS exposure is to stop smoking. In particular, people should avoid smoking indoors, where chemicals from tobacco smoke can settle on surfaces.
According to the American Lung Association, smoking next to an open window does not prevent THS.
A person may want to try to quit smoking to eliminate the risks of THS exposure for themselves and others.
If a person wants to quit smoking to prevent THS exposure and other health risks, they should speak with their doctor for support and advice. A healthcare professional can recommend support groups, nicotine replacement therapies, and other strategies that a person may find helpful.
Alternatively, some health organizations, such as the Centers for Disease Control and Prevention (CDC), provide
THS consists of harmful chemicals from tobacco smoke that absorb into indoor surfaces, furniture, skin, and pet fur. These chemicals can also re-emit into the air and mix with other chemicals in the environment, forming new chemicals that can be harmful to inhale.
Children may be more vulnerable to THS exposure because they typically spend more time on the floor, touch many surfaces with their hands, and may often put objects into their mouths.
Research into the effects of THS exposure on people is limited. However, studies suggest that exposure to THS may negatively affect a person’s health in several ways.
The only way to prevent THS exposure is to keep indoor spaces completely smoke-free. A person may want to consider quitting smoking to prevent THS.
People should speak with a healthcare professional if they are considering quitting smoking. Additionally, a person may want to contact a doctor if they are experiencing any symptoms, such as coughing and difficulty breathing, after exposure to tobacco smoke.