Secondhand Smoke

Summary

Secondhand smoke is a mixture of the smoke that comes from the burning end of a cigarette, cigar, or pipe, and the smoke breathed out by the smoker. It contains more than 7,000 chemicals. Hundreds of those chemicals are toxic and about 70 can cause cancer.

Health effects of secondhand smoke include:

• Ear infections in children
• More frequent and severe asthma attacks in children
• Heart disease and lung cancer in adults who have never smoked

There is no safe amount of secondhand smoke. Even low levels of it can be harmful. The only way to fully protect nonsmokers from secondhand smoke is not to allow smoking indoors.

Centers for Disease Control and Prevention

National Cancer Institute

Find an Expert

• American Cancer Society American Cancer Society
• American Lung Association American Lung Association
• Centers for Disease Control and Prevention Centers for Disease Control and Prevention
• National Cancer Institute National Cancer Institute

Prevention and Risk Factors

• BeTobaccoFree.gov Department of Health and Human Services

Related Issues

• Cancer and Tobacco Use Centers for Disease Control and Prevention
• Health Harms from Secondhand Smoke Campaign for Tobacco-Free Kids
• Health Problems Caused by Secondhand Smoke Centers for Disease Control and Prevention
• Thirdhand Smoke: What Are the Dangers to Nonsmokers? Mayo Foundation for Medical Education and Research

Clinical Trials

• ClinicalTrials.gov: Tobacco Smoke Pollution National Institutes of Health

Statistics and Research

• General Information about Secondhand Smoke Centers for Disease Control and Prevention

Start Here

• Health Risks of Secondhand Smoke American Cancer Society
• Let’s Make the Next Generation Tobacco-Free: Your Guide to the 50th Anniversary Surgeon General’s Report on Smoking and Health Department of Health and Human Services
• Secondhand Smoke National Cancer Institute, Tobacco Control Research Branch
• Secondhand Smoke Centers for Disease Control and Prevention
• Secondhand Smoke and Cancer National Cancer Institute
• Secondhand Smoke and Electronic-Cigarette Aerosols Environmental Protection Agency
• Secondhand Smoke: What It Means to You Surgeon General

Women

• How Smoking Harms Your Child National Cancer Institute, Tobacco Control Research Branch

Journal Articles

• Secondhand Smoke

Teenagers

• Secondhand Smoke Nemours Foundation

Patient Handouts

• Smoking and asthma Medical Encyclopedia