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Indoor Air Quality (IAQ)

Secondhand Tobacco Smoke and Smoke-free Homes

What is Secondhand Smoke?

Secondhand smoke is a mixture of the smoke given off by the burning of tobacco products, such as cigarettes, cigars or pipes and the smoke exhaled by smokers. Secondhand smoke is also called environmental tobacco smoke (ETS) and exposure to secondhand smoke is sometimes called involuntary or passive smoking. Secondhand smoke contains more than 7,000 substances, several of which are known to cause cancer in humans or animals.

  • EPA has concluded that exposure to secondhand smoke can cause lung cancer in adults who do not smoke. EPA estimates that exposure to secondhand smoke causes approximately 3,000 lung cancer deaths per year in nonsmokers.
    • Learn more about lung cancer Exit
    • The 1992 EPA Risk Assessment, “Respiratory Health Effects of Passive Smoking” concluded that environmental tobacco smoke is causally associated with lung cancer in adults and designated ETS as a Group A (known human) carcinogen.
  • Exposure to secondhand smoke has also been shown in a number of studies to increase the risk of heart disease and stroke.

The Science Behind the Risks

Surgeon General Warning: Secondhand Smoke Puts Children at Risk

On June 27th, 2006, the Surgeon General released a major new report on involuntary exposure to secondhand smoke, concluding that secondhand smoke causes disease and death in children and nonsmoking adults. The report finds a causal relationship between secondhand smoke exposure and Sudden Infant Death Syndrome (SIDS), and declares that the home is becoming the predominant location for exposure of children and adults to secondhand smoke.

View the original report by visiting the following links:

The U.S. Environmental Protection Agency (EPA) published a major assessment of the respiratory health risks of passive smoking in 1992 titled “Respiratory Health Effects of Passive Smoking: Lung Cancer and Other Disorders.” The report concluded that exposure to environmental tobacco smoke (ETS) - commonly known as secondhand smoke- is responsible for approximately 3,000 lung cancer deaths each year in nonsmoking adults and impairs the respiratory health of thousands of children.

Key findings:

In adults:

  • ETS is a human lung carcinogen, responsible for approximately 3,000 lung cancer deaths annually in U.S. nonsmokers.
  • ETS has been classified as a Group A carcinogen under EPA's carcinogen assessment guidelines. This classification is reserved for those compounds or mixtures which have been shown to cause cancer in humans, based on studies in human populations.

In children:

  • ETS exposure increases the risk of lower respiratory tract infections such as bronchitis and pneumonia. EPA estimates that between 150,000 and 300,000 of these cases annually in infants and young children up to 18 months of age are attributable to exposure to ETS. Of these, between 7,500 and 15,000 will result in hospitalization.
  • ETS exposure increases the risk of ear infections in children.
  • ETS exposure in children irritates the upper respiratory tract and is associated with a small but significant reduction in lung function.
  • ETS exposure increases the frequency of episodes and severity of symptoms in asthmatic children. The report estimates that up to 1,000,000 asthmatic children have their condition worsened by exposure to environmental tobacco smoke.
  • ETS exposure is a risk factor for new cases of asthma in children who have not previously displayed symptoms.

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ETS and Indoor Air Quality

  • Secondhand smoke, also known as environmental tobacco smoke (ETS), is an indoor air pollutant and a universal asthma trigger.
  • Eliminating secondhand smoke from the indoor environment will improve the indoor air quality.
  • Secondhand smoke can move between rooms of a home and between apartment units.
    • Learn more about smoke-free housing policies, programs and tools.
  • Households within buildings with smoke-free policies have lower PM2.5 compared to buildings without these policies. PM2.5 is a measure of small particles in the air and is used as an indication of air quality. High levels of fine particles in the air can lead to negative health impacts. (Russo, 2014)
  • Prohibiting smoking indoors is the only way to eliminate secondhand smoke from the indoor environment. Ventilation and filtration techniques can reduce, but not eliminate, secondhand smoke. (Bohoc, 2010)

Health Risks to Children with Asthma

  • Asthma is a chronic disease that affects the airways of the lungs and can lead to coughing, trouble breathing, wheezing and tightness in the chest.
  • Asthma is the most common chronic childhood disease affecting 1 in 13 school aged children on average.
  • Secondhand smoke is a universal asthma trigger and can elicit an asthma attack or make asthma symptoms more severe.
  • Exposure to secondhand smoke may cause new cases of asthma in children who have not previously shown symptoms
  • More than half of US children with asthma are exposed to secondhand smoke (quinto, 2013).

What You Can Do:

  • Do not smoke in the house and enforce a smoke-free rule in your home to ensure that all guests smoke outdoors.
  • Encourage your multi-unit housing building to implement a smoke-free policy to eliminate infiltration of secondhand smoke from other units and/or common areas.
  • Find a community asthma programs near you by visiting the Asthma Community Network Utilize free resources to compliment classroom education on the dangers of tobacco use and secondhand smoke (link to resource page).