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Secondhand Smoke

Sure, you know smoking is a bad idea, but you're just hurting yourself, right? Not really. When you smoke, it doesn't just affect you. And it's not just irritating to those around you, it's deadly.

What is secondhand smoke?
Secondhand smoke is the combination of smoke from the burning end of a cigarette and the smoke breathed out by the smoker. It can stay in the air for several hours and travel up to 20 feet.

Did you know secondhand smoke kills?
There is no safe amount of secondhand smoke. Period. Even breathing secondhand smoke for just a short time can hurt your body. Over time, secondhand smoke causes disease and death in kids, teens, and adults—even if they do not smoke. Exposure to secondhand smoke can increase your risk of lung cancer by 20 to 30 percent.

Does secondhand smoke contain harmful chemicals? Yes. Among the more than 7,000 chemicals found in secondhand tobacco smoke, at least 250 are known to be harmful. At least 69 of the toxic chemicals in secondhand tobacco smoke cause cancer. Can you guess where else you can find these cancer-causing poisons?

What does secondhand smoke do to your heart?
Secondhand smoke not only can cause cancer, it can also lead to heart attack or heart disease. About 46,000 nonsmokers die from heart disease each year as a result of secondhand smoke.

How can you protect yourself and others from secondhand smoke?

  • Ask people not to smoke in your home or car
  • Avoid places that allow smoking indoors
  • Choose smoke-free restaurants
  • Tell your friends and family about secondhand smoke

Find out more

NCI Fact sheet, Secondhand Smoke: Questions and Answers
CDC, Secondhand Smoke (SHS) Facts External link disclaimer


Take the secondhand smoke quiz