Secondhand and Thirdhand Smoke

Get the Facts!

There is no risk-free level of exposure to secondhand smoke.

Secondhand smoke is the tobacco smoke exhaled by a person who is smoking or from a burning tobacco product.

  • Even brief exposure to secondhand smoke causes damage that can lead to serious disease and death.
  • Secondhand smoke contains thousands of chemicals. At least 69 of these chemicals are known to cause cancer.
  • Children exposed to secondhand smoke are at a higher risk of health issues, including: Sudden Infant Death Syndrome (SIDS), acute respiratory infections, ear problems, learning disabilities, behavioral problems and more severe asthma.
  • Pets breathe secondhand smoke and, as with humans, exposure is known to cause cancer and illness.

Thirdhand smoke is the tobacco smoke residue that remains after a tobacco product has been put out.

  • Thirdhand smoke clings to hair, skin, clothes, furniture, drapes, walls, carpets and other surfaces. It can build up over time and resist normal household cleaning.
  • Thirdhand smoke contains chemicals that are known to cause cancer.
  • Infants and children are particularly vulnerable to the effects of thirdhand smoke as crawl on the floor and put things that are contaminated in their mouth. Infants exposed to thirdhand smoke are more likely to die from Sudden Infant Death Syndrome (SIDS), and those exposed are at an increased risk for asthma.
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