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Second–hand smoke

Children & second–hand smoke

Second-hand smoke is harmful for everyone, but it’s especially harmful for babies and children. Second-hand smoke can cause ear infections, breathing problems, SIDS, and serious diseases in kids. Kids deserve special protection against second-hand smoke.

Kids should also be protected against third-hand smoke, the smoke that gets trapped in funiture, carpet and fabric, and sticks around even after people butt out.

Why children especially at risk from second-hand and third-hand smoke?

Babies and children are especially vulnerable to second- and third-hand smoke because:

  • They have faster breathing rate: they breathe in more air relative to their body weight, which means they absorb more smoke
  • Their immune systems are less developed
  • They have less power and they're less able to complain about being around smoke
  • They are less able to leave smoky places by themselves

How does second-hand smoke harm children’s health?

Kids who are exposed to second-hand smoke are at higher risk for many serious health problems. Compared to other kids, children who regularly breathe second-hand smoke have:

  • More risk of dying from sudden infant death syndrome (SIDS)1
  • More cough and wheeze 2
  • More cases of asthma, and among kids with asthma, worse asthma symptoms 3, 3
  • More ear infections 4
  • Less lung capacity 5
  • More respiratory tract infections (bronchitis, croup, pneumonia, etc.) 6
  • Lower test scores in math, reading and logic 7
  • More chance of taking up smoking themselves

There is also growing evidence that kids exposed to second-hand smoke are more at risk of developing cancer later in life. 10 And new research suggests that kids who are exposed to second-hand smoke may have more behaviour problems than other kids.8

Second-hand smoke also harms babies before they are born
When pregnant mothers smoke or breathe second-hand smoke, their babies can get serious health problems. It’s important that pregnant women don’t smoke, and that they stay away from second-hand smoke. Read more about smoking and pregnancy.

How many childhood diseases and deaths in Canada can be blamed on second-hand smoke?

The non-profit group Physicians for a Smoke-free Canada estimates that in Canada, second-hand smoke is responsible for: 11

  • 13% of ear infections: about 220,000 ear infections per year in children
  • 26% of tympanostomy tube insertions : about 16,500 per year
  • 24% of tonsillectomies and adenoidectomies: about 2,100 operations per year
  • 13% of asthma cases: about 52,200 cases per year
  • 16% of physician visits for cough: about 200,000 visits per year
  • 20% of all lung infections in children under 5: about 43,600 cases of bronchitis and 19,000 cases of pneumonia per year
  • 136-212 childhood deaths from lower respiratory infection: about 13-20 deaths per year
  • 148 childhood deaths from fires started by tobacco products: about 15 deaths per year
  • About 180-270 deaths per year from Sudden Infant Death Syndrome (SIDS)
How many kids are exposed to second-hand smoke in Canada?

Data collected by Health Canada in 2007 showed that 7% of children under the age of 12 (about 290,042 children) were regularly exposed to second-hand smoke at home 12 . A report based on 2003 data found that 16 % of 12-year-olds were regularly exposed to second-hand smoke in public spaces, and 17% were regularly exposed to second-hand smoke in private vehicles.15

Read more about smoke and kids:

1 McMartin KI, Platt MS, Hackman R, Klein J, Smialek JE, Vigorito R, Koren G. Lung tissue concentrations of nicotine in sudden infant death syndrome (SIDS). J Pediatr. 2002 Feb;140(2):205-9, and Milerad J, Vege A, Opdal SH, Rognum TO. Objective measurements of nicotine exposure in victims of sudden infant death syndrome and in other unexpected child deaths. J Pediatr. 1998 Aug;133(2):232-6. The following British study concluded that SIDS deaths could be reduced by two-thirds if parents did not smoke: Peter Blair et al. Smoking and the sudden infant death syndrome: results from 1993-5 case-control study for confidential inquiry into stillbirths and deaths in infancy. British Medical Journal, 1996: 313.

2 Gergen Peter J., Fowler Jean A., Maurer Kurt R., Davis William W., and Overpeck, Mary D. The Burden of Environmental Tobacco Smoke Exposure on the Respiratory Health of Children 2 Months Through 5 Years of Age in the United States: Third National Health and Nutrition Examination Survey, 1988 to 1994. Pediatrics 101(2) February 1998, p. e8. and Mannino DM, et al. Environmental Tobacco Smoke Exposure and Health Effects in Children. Tobacco Control. 1996; 5(1): 13-18.

3 Mannino, David M., David M. Homa, Stephen C. Redd. Involuntary Smoking and Asthma Severity in Children. Chest. 2002;122:409-415.

4 Adair-Bischoff, Carol E., Reginald S. Sauve. Environmental Tobacco Smoke and Middle Ear Disease in Preschool-Age Children. Arch Pediatr Adolesc Med. 1998;152:127-133.

5 Samet, JM. Synthesis: The Health Effects of Tobacco Smoke Exposure on Children. World Health Organisation report, published 1999 and available from: (PDF)

6 Ugnat AM, Mao Y, Miller AB, et al. Effects of residential exposure to environmental tobacco smoke on Canadian children. Can J Public Health 1990 Sep-Oct;81(5):345-9.

7 Collins BN, Wileyto EP, Murphy MF, Munafò MR. Adolescent environmental tobacco smoke exposure predicts academic achievement test failure. J Adolesc Health. 2007 Oct;41(4):363-70 and Yolton K, Dietrich K, Auinger P, Lanphear BP, Hornung R. Exposure to environmental tobacco smoke and cognitive abilities among U.S. children and adolescents. ,em>Environ Health Perspect. 2005 Jan;113 (1):98-103.

8 Gatzke-Kopp LM, Beauchaine TP. Direct and passive prenatal nicotine exposure and the development of externalizing psychopathology. Child Psychiatry Hum Dev. 2007 Dec;38(4):255-69.

9 Bailey JA, Hill KG, Oesterle S, Hawkins JD. Linking substance use and problem behavior across three generations. J Abnorm Child Psychol. 2006 Jun;34(3):263-92.

10International Agency for Research on Cancer. Tobacco smoke and involuntary smoking. Lyon, France: IARC Press; 2004. (IARC Monographs; 83) and Sandler DP, Everson RB, Wilcox AJ, et al. Cancer risk in adulthood from early life exposure to parents’ smoking. Am J Public Health 1985. May;75(5):487-92.

11 These figures extrapolated for the Canadian context by Physicians for a Smoke-Free Canada, based on findings in these US-based studies: Joseph diFranza and Robert Lew, Morbidity and Mortality in Children Associated with the Use of Tobacco Products by Other People, Paediatrics, 1996, 97:560-568] and California EPA. Final Report: Health Effects of Exposure to Environmental Tobacco Smoke, Sept. 1997.

12Health Canada. Canadian Tobacco Use Monitoring Survey (CTUMS) 2007: Summary of Annual Results for 2007.

13 Pérez, Claudio. Second-hand smoke exposure- Who’s at risk? Statistics Canada Health Reports Vol 16 (1). October 2004. Available from