- Also called:
- environmental tobacco smoke
- Related Topics:
- passive smoking
secondhand smoke
-
What is secondhand smoke?
Secondhand smoke, also known as environmental tobacco smoke (ETS), is a mix of exhaled smoke and the smoke emitted from burning tobacco products. It contains thousands of chemicals, with approximately 70 known to cause cancer, such as benzene and formaldehyde. Inhaling secondhand smoke can cause serious health issues in nonsmokers, including respiratory infections, asthma, and increased risk of cardiovascular disease. Children exposed to secondhand smoke are more prone to asthma, chronic cough, and reduced lung function. Because of the dangers of ETS, many places have implemented smoking bans in public spaces.
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Where does secondhand smoke come from?
Secondhand smoke, also known as environmental tobacco smoke (ETS), comes from the smoke exhaled by a smoker (mainstream smoke) and the smoke that rises directly from a smoldering tobacco product (sidestream smoke). Tobacco products that produce secondhand smoke include cigarettes, cigars, hookahs, and pipes. Exposure to secondhand smoke can occur anywhere, indoors or outdoors. It is bad and can cause illnesses, including cancer, respiratory infections, and asthma.
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How can secondhand smoke affect people who don’t smoke?
Secondhand smoke, a mix of exhaled smoke and that from burning tobacco products, contains thousands of chemicals, including about 70 carcinogens. Inhaling it raises the risk of lung cancer and may increase the risk of other cancers, such as breast cancer. Children are particularly vulnerable and may face a higher risk of leukemia or lymphoma.
Secondhand smoke can also cause cardiovascular issues and respiratory damage, triggering allergy-like reactions and worsening existing conditions like asthma or COPD. Chemicals in the smoke can harm blood vessels, increasing the risk of clots, stroke, and heart attack. Eye and skin irritation are also common effects.
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Why is secondhand smoke especially harmful to children?
Secondhand smoke is especially harmful to children because their bodies are still developing, making them more vulnerable to its toxic effects. Children breathe faster than adults, inhaling more pollutants per unit of body weight. Exposure to secondhand smoke can lead to increased risks of respiratory infections like bronchitis and pneumonia, more frequent and severe asthma attacks, and reduced lung growth and function. Additionally, children exposed to secondhand smoke may have a higher risk of developing leukemia or lymphoma.
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What health problems can be caused by secondhand smoke exposure?
Secondhand smoke is a mixture of exhaled smoke and the smoke from burning tobacco products. It contains over 7,000 chemicals, including about 70 carcinogens.
Exposure to secondhand smoke can cause:
* Lung cancer
* Increased risk of other cancers, such as breast cancer, leukemia, and lymphoma
* Cardiovascular disease
* Respiratory issues, such as coughing, wheezing, and shortness of breath
* Eye and skin irritation
* Increased risk of blood clots, heart attack, and stroke3 Britannica SourcesCreated from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles. -
What are some ways to reduce exposure to secondhand smoke?
Secondhand smoke contains over 7,000 chemicals, with around 70 known to cause cancer, such as benzene and formaldehyde. It significantly raises the risk of cardiovascular diseases and respiratory damage, causing symptoms like coughing and shortness of breath.
To reduce exposure, clean air laws have been implemented worldwide, banning smoking in public areas like restaurants and workplaces. These laws aim to protect nonsmokers from toxins in environmental tobacco smoke. Smoke-free policies not only protect nonsmokers but also encourage smokers to quit.
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secondhand smoke, smoke that is released into the air, from tobacco and non-tobacco products, being either exhaled by the smoker (mainstream smoke) or rising directly from a smoldering product (sidestream smoke). Nonsmokers who are routinely exposed to secondhand smoke are at increased risk for some of the same diseases that afflict smokers, particularly lung cancer and cardiovascular disease. The inhalation of secondhand smoke is sometimes referred to as passive smoking.
Examples of tobacco products from which secondhand smoke originates include cigarettes, cigars, hookahs, and pipes. Secondhand marijuana smoke, another significant source of secondhand smoke, originates from smoked cannabis products. Exposure to secondhand smoke can occur indoors, such as in restaurants or workplaces, or outdoors. The extent to which secondhand smoke exposure has an impact on health generally is related to proximity and ventilation as well as to whether exposed persons have predisposing factors, such as preexisting respiratory or cardiovascular conditions, that increase the risk of adverse health effects.
Harmful effects
Secondhand smoke contains some 7,000 different chemicals, nearly 70 of which are known carcinogens (cancer-causing substances). Examples of carcinogens found in secondhand smoke include acetaldehyde, benzene, cadmium, formaldehyde, and 1,3–butadiene (a toxic gas). Exposure to such chemicals primarily raises lung cancer risk; however, inhalation of secondhand smoke is suspected of also increasing the risk of some other cancers, including breast cancer. Children exposed to secondhand smoke may be at increased risk of leukemia or lymphoma.
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Secondhand smoke also significantly increases the risk of cardiovascular disease as well as various forms of respiratory damage other than lung cancer. Indeed, many chemicals in secondhand smoke irritate the airways of the respiratory tract, triggering allergy-like reactions, exacerbating existing respiratory or cardiovascular health conditions, or increasing the risk of such conditions developing in previously unaffected individuals. Allergy-like symptoms, such as coughing, wheezing, and shortness of breath, are common among nonsmokers following exposure to secondhand smoke. Such symptoms may be linked to bronchial hyperreactivity, in which the airways of the respiratory tract exhibit increased sensitivity to inhaled irritants, leading to airway constriction (narrowing). Bronchial hyperreactivity is especially pronounced in persons with conditions such as asthma or chronic obstructive pulmonary disease (COPD).
Chemicals in secondhand smoke are known to cause direct damage to blood vessels, increasing the risk of blood clots and stroke or heart attack. Tobacco smoke also often causes eye irritation and may even provoke skin reactions, such as itching or rash.
Secondhand marijuana smoke
Many of the same toxic chemicals found in tobacco smoke are also found in secondhand marijuana smoke. In fact, some of the same chemicals found in both types of secondhand smoke actually occur in greater amounts in marijuana smoke; for example, hydrogen cyanide and nitric oxide concentrations are three to five times higher in marijuana smoke than in tobacco smoke. Marijuana smoke may be further contaminated with insecticides or pesticides used on cannabis plants. As a result, exposure to secondhand marijuana smoke carries significant risks to respiratory and cardiovascular health.
Secondhand marijuana smoke also contains tetrahydrocannabinol (THC), the primary psychoactive chemical in cannabis. The presence of THC poses unique risks to nonsmokers, since those who passively inhale marijuana smoke are at risk of subsequently experiencing anxiety, paranoia, restlessness, and other psychoactive effects associated with THC. THC can be detected in persons exposed to secondhand marijuana smoke, with levels ranging from low to high, depending on exposure. Other effects of exposure to secondhand marijuana smoke may include eye irritation, headache, fatigue, and nausea.
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Regulation
Clean air laws that prohibit cigarette smoking are widespread. In the 1980s and ’90s, such laws typically required nonsmoking areas to be established in restaurants and workplaces. However, the finding that toxins in environmental smoke could easily diffuse across large spaces led to much stronger bans. Since 2000 many cities, states, and regions worldwide have implemented complete smoking bans in restaurants, taverns, and workplaces.
In places where marijuana has been legalized, bans on smoking may parallel bans already in place for tobacco smoking. In California, for example, marijuana smoking is prohibited in areas where tobacco smoking is banned.