According to the U.S. Surgeon General, there is no safe level of exposure to secondhand smoke. Even brief moments around smoke can be harmful to a person's health. Exposure to secondhand smoke is especially unsafe for infants and children because their bodies and lungs are still developing and growing. Yet, more than half of all young children in the United States are exposed to secondhand smoke.

What is secondhand smoke?

Secondhand smoke refers to both the smoke exhaled from a smoker's lungs and the smoke from a burning cigarette, cigar, or pipe. When a non-smoker inhales (breathes in) secondhand smoke, it is called passive smoking or involuntary smoking.

Inhaling secondhand smoke is like you are actually smoking. Many of the harmful substances in tobacco stay in the air; if you inhale them, they go into your lungs and bloodstream. Secondhand smoke is a poisonous cocktail of hundreds of chemicals proven to harm human health, including more than 60 substances known to cause cancer, such as lead, carbon monoxide, arsenic, ammonia, formaldehyde, and a type of cyanide.

Health risks to children from secondhand smoke

Research shows that secondhand smoke increases children's risk of a variety of health problems. In fact, the U.S. Surgeon General has stated that secondhand smoke causes premature death and disease in children and adults who do not smoke. For children, secondhand smoke exposure raises the risk of the following conditions:

• Ear infections
• Asthma attacks
• Lung infections, such as bronchitis and pneumonia
• Coughing and wheezing
• Sudden Infant Death Syndrome (SIDS)
• Heart disease
• Cancer

Ongoing research continues to find additional links between secondhand smoke and children's well-being, including evidence of links to mental health issues and problems with children's ability to learn.

Protecting your children from secondhand smoke

The only way to fully protect children from secondhand smoke is to make sure they are not around people who are smoking, especially indoors. Strategies like opening windows, using a fan, or turning on an air conditioner do not work. This is why many states have banned smoking in restaurants and other public buildings.

Here are some ways you can protect your family from secondhand smoke:

• Keep your home and car smoke-free. This includes making sure family, friends, and visitors never smoke inside your house or vehicle.
• Make sure the places where your child spends time—such as daycare, school, or after-school programs—do not allow smoking.
• Ask caregivers and relatives not to smoke around your children.
• Keep your family away from places that allow smoking inside. For instance, eat in restaurants that are smoke-free. Non-smoking sections do not protect from secondhand smoke.
• If you are pregnant, avoid being around people who are smoking.
• If you smoke, consider quitting. In addition to the potential effects on your children, smoking is harming your own health. Quitting can be difficult, but there are many resources to help you, including talking with your doctor about how to quit smoking.

Keeping your children away from secondhand smoke may have the added benefit of preventing your children from becoming smokers themselves. One study showed that children of smokers are less likely to start smoking if their parents routinely sit in smoke-free areas of public places. Not smoking in the home also helps prevent teen smoking, the study found.

More Information

Tobacco and Cancer

Quitting Smoking

Health Risks of Waterpipes, Smokeless Tobacco, and E-cigarettes

Additional Resources

National Cancer Institute: Secondhand Smoke and Cancer

Centers for Disease Control and Prevention: Secondhand Smoke

Campaign for Tobacco-Free Kids

Last Updated: May 06, 2011