Secondhand Smoke

What is secondhand smoke?

Secondhand smoke is:

  • The smoke given off by the burning end of a cigarette, pipe, or cigar
  • The smoke breathed out by smokers

When nonsmokers breathe this smoke, it is called passive smoking.

Is secondhand smoke harmful?

Passive smoking is dangerous. Every time someone smokes, poisonous chemicals go into the air. Many of these chemicals can cause cancer. Each year, many nonsmokers die from lung cancer as a result of breathing secondhand smoke. Secondhand smoke can also lead to:

  • Death from heart disease
  • Worsened asthma symptoms and more asthma attacks
  • Irritation of the eyes, nose, and throat
  • Cancer of the cervix, breast, throat, and sinuses

Passive smoking increases the risk of SIDS (sudden infant death syndrome). Babies whose mothers smoke during or after pregnancy are more likely to die of SIDS than babies whose mothers do not smoke.

Children who are around secondhand smoke are more likely to have asthma and to get more colds and ear infections. Secondhand smoke affects kidney function and can increase blood pressure in children, especially if both parents smoke in the home. And there is a greater chance that children of smokers will become smokers. Secondhand smoke may also increase the risk that children will have attention-deficit disorder (ADHD) or a learning disability.

If you are around someone who smokes every day, your risk of health problems is almost as high as if you smoke. If you live or work in a smoky place:

  • You increase your chances of having a heart attack by 50%.
  • You double your chances of getting cancer or asthma.

If you are exposed to cigarette smoke while pregnant:

  • You have a greater risk of losing your baby during pregnancy.
  • Your baby may have a low birth weight or be born early.

How close to tobacco smoke do I have to be for it to hurt me?

Even if you drink or eat in nonsmoking areas of bars and restaurants, you may still breathe in dangerous levels of smoke if you are near a smoker. The closer you are to the smoke coming from the end of a cigarette, cigar, or pipe, the worse it is for you. You should stay at least 20 feet away from people smoking outdoors. There is no safe level of tobacco smoke indoors. Being in a car with a smoker is also bad, even if the windows are open.

You can also be exposed to dangerous levels in any building where people smoke. Smoke and the chemicals from it stay in dust and on carpet, floors, counters, and other surfaces. This is called third hand smoke.

What are some of the ways to avoid secondhand smoke?

  • Try to avoid places where people smoke.
  • Don’t smoke in your house or car and don’t let others do so.
  • Ask your employer to ban smoking indoors. That is the only way to protect nonsmokers from secondhand smoke. Air cleaning systems, air conditioning, or separate smoking rooms do not protect you from secondhand or third hand smoke.
  • Make sure your child’s day-care, school, and after-school programs are smoke free.
  • Choose restaurants and bars that are smoke-free.

For more information, contact:

Developed by RelayHealth.
Adult Advisor 2015.1 published by RelayHealth.
Last modified: 2015-01-02
Last reviewed: 2015-01-02
This content is reviewed periodically and is subject to change as new health information becomes available. The information is intended to inform and educate and is not a replacement for medical evaluation, advice, diagnosis or treatment by a healthcare professional.
Copyright ©1986-2015 McKesson Corporation and/or one of its subsidiaries. All rights reserved.

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