• USA Flag Image

Text Size: A A A

Secondhand Smoke

Father talking to daughter about the dangers of secondhand smoke. Learn more at www.BeTobaccoFree.gov.

What is secondhand smoke?

Secondhand smoke is the combination of smoke from the burning end of a cigarette and the smoke exhaled by smokers. You can be exposed to secondhand smoke in homes, cars, the workplace, and public places, such as bars, restaurants, and recreational settings.

In the United States, the source of most secondhand smoke is cigarettes, followed by pipes, cigars, and other tobacco products. Secondhand smoke contains more than 7,000 chemicals. Hundreds of the chemicals are toxic and about 70 are known to cause cancer.

Can secondhand smoke make me sick?

There is no safe exposure to secondhand smoke. When you are around a person who is smoking, you inhale the same dangerous chemicals as the smoker. Breathing even a little secondhand smoke can be dangerous.

Inhaling secondhand smoke can cause lung cancer in nonsmoking adults. In the United States, approximately 3,000 adults die each year due to lung cancer from secondhand smoke exposure. According to the U.S. Surgeon General, living with a smoker increases a nonsmoker’s chances of developing lung cancer by 20% to 30%.

Exposure to secondhand smoke can also cause coronary heart disease and have negative effects on your blood and blood vessels, increasing your risk of a heart attack. Heart disease caused by secondhand smoke kills approximately 46,000 nonsmokers every year. People who already have heart disease are at an especially high risk of suffering negative effects from breathing secondhand smoke and should avoid even brief exposure to it.

Because studies show that  laws banning smoking in public places help improve worker and customer health, many states and communities have laws making workplaces, public places, restaurants, and bars smoke-free. But millions of children and adults still breathe secondhand smoke in their homes, cars, workplaces, and in public places.   

Infographic showing how secondhand smoke is toxic. For a text-version of the information displayed on the infographic, use the link after the image. Learn more at www.BeTobaccoFree.gov.

Infographic text-only version.


How does secondhand smoke affect pregnant women, babies, and children?

Pregnant women who breathe secondhand smoke are more likely to have lower birth weight babies than women who do not breathe secondhand smoke. Once born, babies who are around cigarette smoke are more likely to:

Secondhand smoke can cause serious health problems in children, including:

  • Frequent lower respiratory illness
  • Wheezing and coughing
  • More frequent and severe asthma attacks
  • Ear infections

For these reasons, women who are pregnant are advised to avoid environments where heavy concentrations of secondhand smoke linger.

Learn how tobacco use affects you and your family during and after pregnancy.

Learn more about: