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Improving Air Quality in Your Community

Indoor Air: Reduce Exposure to Environmental Tobacco Smoke (ETS) - Additional Information

Information provided for informational purposes onlyNote: EPA no longer updates this information, but it may be useful as a reference or resource.

This information will help you gain a better understanding of questions related to ETS. The sections below provide more information on this topic.

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What is ETS?

  • Environmental tobacco smoke (ETS), also known as secondhand smoke, is a mixture of the smoke given off by the burning end of a cigarette, pipe, or cigar, and the smoke exhaled from the lungs of smokers.
  • ETS contains more than 4,000 substances, more than 40 of which are known to cause cancer in humans or animals. Many of these substances are strong irritants.
  • Exposure to ETS is called involuntary smoking or passive smoking.

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What are the health effects of ETS?

Environmental tobacco smoke contains pollutants such as hazardous air pollutants (HAPs). These pollutants can contribute to health problems that may impact workers, children, families, and the community.

  • Health Effects
    • EPA has classified ETS as a known cause of lung cancer in humans.
    • Passive smoking causes approximately 3,000 lung cancer deaths in non-smokers each year.
    • Exposure to ETS causes irritation of the eyes, nose, and throat.
    • ETS can irritate the lungs and lead to coughing, excess phlegm, chest discomfort, and reduced lung function.
    • ETS may affect the cardiovascular system. Some studies have linked exposure to ETS with the onset of chest pain.
  • Special Health Effects Concerns in Children
    • Exposure of young children to ETS can affect their developing lungs.
    • ETS can cause serious health effects in young children and infants whose parents smoke. Each year, ETS is responsible for between 150,000 and 300,000 lower respiratory tract infections in infants and children under the age of 18 months.
    • Exposure to ETS increases the number of asthma episodes and severity of symptoms in hundreds of thousands of asthmatic children. Between 200,000 and 1,000,000 asthmatic children have worsened conditions due to exposure to ETS.
    • ETS can cause thousands of non-asthmatic children to develop the condition each year.
  • Check out the additional information EPA has developed about the health effects of ETS.

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What are the potential benefits of controlling ETS?

  • Reducing the risk of respiratory diseases in children from ETS.
  • A decline in the incidence of lung cancer in adults. California's comprehensive approach to smoking prevention and cessation yielded an astounding 14% decline in the incidence of lung cancer from 1988 to 1997. Also, smoking rates within California have declined more rapidly compared with the rest of the country.

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