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Secondhand Smoke - Fact Sheet (June 2006)

Definition

  • Secondhand smoke, also known as environmental tobacco smoke, is a complex mixture of gases and particles that includes smoke from the burning cigarette, cigar, or pipe tip (sidestream smoke) and exhaled mainstream smoke. 1
     
  • Secondhand smoke is a known human carcinogen (cancer-causing agent). More than 50 compounds in secondhand smoke have been identified as known or reasonably anticipated human carcinogens. Secondhand smoke contains at least 250 chemicals that are known to be toxic or carcinogenic. 1
     
  • People are exposed to secondhand smoke in homes, vehicles, workplaces, and in public places such as restaurants, bars, and casinos. Homes and workplaces are the predominant locations for secondhand smoke exposure. 2
     

Health Effects

  • Secondhand smoke exposure causes heart disease and lung cancer in nonsmoking adults. Nonsmokers who are exposed to secondhand smoke at home or work increase their heart disease risk by 25–30 percent and their lung cancer risk by 20–30 percent. 2 Secondhand smoke exposure has immediate adverse effects on the cardiovascular system. 2
     
  • Secondhand smoke causes sudden infant death syndrome (SIDS), acute respiratory infections, ear problems, and more frequent and severe asthma attacks in children. Secondhand smoke exposure causes respiratory symptoms in children and slows their lung growth. 2
     
  • There is no risk-free level of secondhand smoke exposure. Even brief exposure can be dangerous. 2
     

Current Estimates

  • Levels of a chemical called cotinine, which is a marker of exposure to nicotine and secondhand smoke in nonsmokers, fell by 70 percent from 1988-91 to 2001-02. Over this same time period, the proportion of nonsmokers with detectable cotinine levels was halved from 88 percent to 43 percent. 3
     
  • More than 126 million nonsmoking Americans continue to be exposed to secondhand smoke in homes, vehicles, workplaces, and public places. 2
     
  • Almost 60 percent of U.S. children aged 3–11 years—or almost 22 million children—are exposed to secondhand smoke. 2
     
  • About 25 percent of children aged 3-11 years live with at least one smoker, as compared to only about 7 percent of nonsmoking adults. 2
     
  • The California Environmental Protection Agency estimates that secondhand smoke exposure causes approximately 3,400 lung cancer deaths and 22,700–69,600 heart disease deaths annually among adult nonsmokers in the United States. 4
     
  • Secondhand smoke exposure is responsible for an estimated 150,000–300,000 new cases of bronchitis and pneumonia in children aged less than 18 months, resulting in 7,500–15,000 hospitalizations. 5
     

References

1. National Toxicology Program. 9th Report on Carcinogens , 2000. Research Triangle Park, NC: U.S. Department of Health and Human Sciences, National Institute of Environmental Health Sciences, 2000. http://ntp.niehs.nih.gov/ntp/roc/eleventh/profiles/s176toba.pdf
(PDF–219K). Accessed June 2006.
 

2. U.S. Department of Health and Human Services. The Health Consequences of Involuntary Exposure to Tobacco Smoke: A Report of the Surgeon General . Atlanta, Georgia: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, Coordinating Center for Health Promotion, National Center for Chronic Disease Prevention and Health Promotion, Office on Smoking and Health, 2006.
http://www.surgeongeneral.gov/library/secondhandsmoke/report/
 

3. Pirkle JL, Bernert JT, Caudill SP, Sosnoff CS, Pechacek TF. Trends in the exposure of nonsmokers in the U.S. population to secondhand smoke: 1988–2002. Environmental Health Perspectives 2006; 114(6):853–858.
 

4. California Environmental Protection Agency. Proposed Identification of Environmental Tobacco Smoke as a Toxic Air Contaminant . California Environmental Protection Agency, final report, September 29, 2005, approved by Scientific Review Panel on June 24, 2005. http://www.arb.ca.gov/toxics/ets/finalreport/finalreport.htm. Accessed June 2006.
 

5. United States Environmental Protection Agency (EPA). Respiratory Health Effects of Passive Smoking: Lung Cancer and Other Disorders . Office of Research and Development, EPA/600/6-90/006F, Washington, D.C., December 1992. http://cfpub2.epa.gov/ncea/cfm/recordisplay.cfm?deid=2835. Accessed June 2006.
 
Also published as: National Institutes of Health. National Cancer Institute. Respiratory Health Effects of Passive Smoking: Lung Cancer and Other Disorders: The Report of the U.S. Environmental Protection Agency. Smoking and Tobacco Control Monograph Number 4. NIH Publication No. 93-3605, Washington, D.C., August 1993.

Note: More recent information may be available at the CDC'S Office on Smoking and Health Web site: http://www.cdc.gov/tobacco.

For Further Information

Centers for Disease Control and Prevention
National Center for Chronic Disease Prevention and Health Promotion
Office on Smoking and Health

E–mail: tobaccoinfo@cdc.gov
Phone: 1–800–CDC–INFO

Media Inquiries: Contact the Office on Smoking and Health press line at 770-488-5493.