How Secondhand Smoke Hurts Children

Mom smoking next to reading daughter on a couch

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Secondhand smoke, also known as environmental tobacco smoke, or ETS, is a combination of exhaled cigarette smoke (mainstream smoke) and smoke that comes from the end of a smoldering cigarette (sidestream smoke). It is a nasty mixture of more than 7,000 chemicals, 250 of which have been identified as poisonous, and upwards of 70 that are carcinogenic.

According to the 2006 report of the Surgeon General, The Health Consequences of Involuntary Exposure to Tobacco Smoke, there is no safe level of exposure to secondhand smoke.


Children face a greater risk than adults of the negative effects of secondhand smoke. When the air is tainted with cigarette smoke, young, developing lungs receive a higher concentration of inhaled toxins than do older lungs because a child's breathing rate is faster than that of adults.

Adults breathe in and out approximately 14 to 18 times a minute, and newborns can breathe as many as 60 times a minute. Up until a child is about 5 years old, the respiratory rate is quite fast.

Young children have little control over their surroundings.

Babies can't move to another room because the air is smoky. They depend on the adults in their lives to make sure their environment is safe.

Scientists have uncovered numerous risks associated with secondhand smoke for young children and the research continues. To date, there are plenty of sobering facts about how this toxic air damages the health of our kids.

Impact on Babies in the Womb

The way affects of secondhand smoke on babies in the womb includes:

  • Babies whose mothers smoke during pregnancy often weigh less at birth than those born to non-smoking mothers. Low birth weight is a leading cause of infant death.
  • Babies whose mothers smoke during pregnancy are at increased risk for developmental issues, such as learning disabilities and cerebral palsy.

Impact on Children's Health

The impact of secondhand smoke on children includes:

  • Babies who are exposed to secondhand smoke after birth have twice the risk of SIDS (sudden infant death syndrome) as babies who aren't exposed. Babies whose mothers smoked before and after birth carry three to four times the risk of SIDS.
  • Among children under 18 months of age in the United States, secondhand smoke is associated with 150,000 to 300,000 cases of lower respiratory tract infections, like bronchitis or pneumonia each year.
  • The EPA estimates that between 200,000 and 1,000,000 kids with asthma have their condition worsened by secondhand smoke. Passive smoking may also be responsible for thousands of new cases of asthma every year.
  • Children in smoking households experience more middle ear infections. Inhaled cigarette smoke irritates the eustachian tube, and the subsequent swelling leads to infections, which are the most common cause of hearing loss in children.
  • The lungs of children who regularly breathe in secondhand smoke develop more slowly.
  • Research has uncovered evidence that suggests secondhand smoke may be related to childhood leukemia, lymphoma, and brain tumors. However, to date, that evidence is insufficient to link these childhood cancers with secondhand smoke definitively.


Below are important facts about secondhand smoke:

  • On average, children have more exposure to secondhand smoke than non-smoking adults.
  • Cotinine levels in children between 3 and 11 years old are more than double that of non-smoking adults.
  • Kids who live in nonsmoking homes that are in multi-family dwellings (apartments, condos) have approximately 45% higher cotinine levels than children who live in nonsmoking single-family homes.
  • An alarming 90% of the exposure kids get to secondhand smoke comes from their parents.
  • Over half of American children breathe in secondhand smoke in cars, homes, and public places where smoking is allowed.

ThirdHand Smoke

With increasing awareness, new risks sometimes emerge. Thirdhand smoke is an example. Toxic particulate matter in cigarette smoke settles on surfaces and stays put, along with the residue from gases in cigarette smoke.

This hazard isn't healthy for anyone but is a particular concern for small children who crawl on hands and knees and play with toys with fingers than then go into their mouths. 

Minimizing the Risks

The only way to really protect little children is absolute cessation, however, it's also important to keep your child away from other smokers and, if you do smoke, to do so in a way that won't expose them to secondhand or thirdhand smoke.

  • Don't smoke inside your house and don't let anyone else, either. Opening windows or using air filters is not enough to protect people from secondhand smoke in an enclosed space.
  • Don't smoke in your car. Even if your kids aren't with you, remember that toxins settle on surfaces and they'll be exposed to them.
  • Avoid any indoor spaces (restaurants, sporting events, friend's houses where smoking occurs, etc.) where your kids will be exposed to secondhand smoke.
  • Give some distance to smokers in outdoor spaces. Yes, outdoor air dilutes cigarette smoke, but if the wind is blowing in your direction, you and your children could still breathe in a lung full of toxic air.

A Word From Verywell

With upwards of 70 carcinogenic and 250 poisonous known chemical components, it is clear that air laden with secondhand smoke is toxic and unsafe for anyone, especially our kids. It is up to us to provide them with healthy air to breathe.

If you smoke, please make sure that you do all that you can to protect others from the secondhand smoke you create.

Better yet, use the resources below to help you get started with smoking cessation.

It is never too late to stop smoking, and the work it takes to achieve is minor when compared to the benefits you'll enjoy once you do.

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Article Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. National Cancer Institute. Harms of cigarette smoking and health benefits of quitting. Updated December 2017.

  2. Stanford Children’s Hospital. Breathing problems.

  3. El-ardat MA, Izetbegovic S, El-ardat KA. Effect of cigarette smoking in pregnancy on infants anthropometric characteristics. Mater Sociomed. 2014;26(3):186-7.  doi:10.5455/msm.2014.26.186-187

  4. Centers for Disease Control and Prevention. Infant mortality. Updated March 2019.

  5. National Cancer Institute. Secondhand Tobacco Smoke (Environmental Tobacco Smoke). Updated February 2019.

  6. Centers for Disease Control and Prevention. Secondhand smoke (SHS) facts. Updated January 2018.

  7. Cinar N, Dede C, Cevahir R, Sevimli D. Smoking status in parents of children hospitalized with a diagnosis of respiratory system disorders. Bosn J Basic Med Sci. 2010;10(4):319-22.  doi:10.17305/bjbms.2010.2679

  8. Jacob P, Benowitz NL, Destaillats H, et al. Thirdhand Smoke: New Evidence, Challenges, and Future Directions. Chem Res Toxicol. 2017;30(1):270-294.  doi:10.1021/acs.chemrestox.6b00343

Additional Reading
  • American Cancer Society. Secondhand Smoke.
  • Centers for Disease Control and Prevention. 2010 Surgeon General's Report: How Tobacco Smoke Causes Disease.
  • Centers for Disease Control and Prevention. Secondhand Smoke Factsheet.
  • U.S. Dept. of Health and Human Services. Surgeon General Reports. The Health Consequences of Involuntary Exposure to Tobacco Smoke. Health Effects of Secondhand Smoke in Children.
  • United States Environmental Protection Agency. Health Effects of Exposure to Secondhand Smoke.