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Secondhand smoke facts

What is secondhand smoke?

Secondhand smoke is also known as environmental tobacco smoke (ETS) or passive smoke. It is a mixture of 2 forms of smoke that comes from burning tobacco:
  • sidestream smoke: smoke that comes from the end of a lighted cigarette, pipe, or cigar
  • mainstream smoke: smoke that is exhaled by a smoker

Secondhand smoke is harmful to children.

11% of children aged 6 years and under are exposed to ETS in their homes on a regular basis (4 or more days per week). Parents are responsible for 90% of children's exposure to secondhand smoke. The developing lungs of young children are severely affected by secondhand smoke. Children have higher breathing rates than adults. Children have little control over their indoor environments. Children receiving high doses of secondhand smoke, such as those with smoking mothers, run the greatest risk of damaging health effects. For children, secondhand smoke can cause:
  • Premature death
  • Asthma attacks and severity of symptoms
  • Lower respiratory tract infections like pneumonia and bronchitis.
  • Inner Ear Infections
  • Increases the risk of Sudden Infant Death Syndrome

Secondhand smoke can hurt your furry friends

Your furry friends don't just inhale smoke; the smoke particles are also trapped in their fur and ingested when they groom themselves with their tongues. A study published in the American Journal of Epidemiology found that dogs in smoking households had a 60 percent greater risk of lung cancer; a different study showed that long-nosed dogs, such as collies or greyhounds, were twice as likely to develop nasal cancer if they lived with smokers. Another vet study found that cats whose owners smoked were three times as likely to develop lymphoma, the most common feline cancer. For your pets, secondhand smoke may cause:
  • Respiratory infections
  • Lung inflammation
  • Asthma
  • Slower lung growth
  • Cancer
  • Lymphoma in cats

More bad news about secondhand smoke?

  1. Tobacco smoke contains over 7,000 chemical compounds. More than 60 of these are known or suspected to cause cancer.
  2. There is no safe level of exposure to secondhand smoke.
  3. Secondhand smoke is classified as a "known human carcinogen" (cancer-causing agent) by the US Environmental Protection Agency (EPA), the US National Toxicology Program, and the International Agency for Research on Cancer (IARC), a branch of the World Health Organization.
  4. Secondhand smoke causes premature death and disease in children and in adults who do not smoke.
  5. Secondhand smoke immediately affects the heart and blood circulation in a harmful way. Over a longer time it also causes heart disease and lung cancer.
  6. Many millions of Americans, both children and adults, are still exposed to secondhand smoke in their homes and workplaces despite a great deal of progress in tobacco control.
  7. The only way to fully protect non-smokers from exposure to secondhand smoke indoors is to prevent all smoking in that indoor space or building. Separating smokers from non-smokers, cleaning the air, and ventilating buildings cannot keep non-smokers from being exposed to secondhand smoke.


Centers for Disease Control, Report of the Surgeon General 2006, The US National Toxicology Program, The International Agency for Research on Cancer (IARC), a branch of the World Health Organization.