|Last updated: January 2017
Suggested citation: Campbell MA, Ford C, & Winstanley MH. Ch 4. The health effects of secondhand smoke. 4.5 Prevalence of exposure to secondhand smoke in the home. In Scollo, MM and Winstanley, MH [editors]. Tobacco in Australia: Facts and issues. Melbourne: Cancer Council Victoria; 2017. Available from http://www.tobaccoinaustralia.org.au/chapter-4-secondhand/4-5-prevalence-of-exposure-to-shs-in-the-home
Although most Australian non-smokers are not exposed to secondhand smoke in the home environment,1 for those individuals who do live with one or more smokers, the home can be an important source of exposure to secondhand smoke.2
The National Drug Strategy Household Survey provides the most recent data published on population prevalence of exposure to secondhand smoke in Australia. Exposure to secondhand smoke in the home for non-smoking children, adolescents and adults has been steadily decreasing.3 This reflects a continuing decline in the prevalence of smoking as well as an increase in smokers who confine their smoking to outside the home environment. Public awareness of the health dangers of secondhand smoke has increased over time (see Section 4.16), and it is likely that increased regulation of smoking in the workplace and in public places over the past decade has also influenced attitudes to smoking in the home.2, 4
Levels of exposures to secondhand smoke in other settings, including the workplace and venues such as hotels, bars and restaurants and other indoor and outdoor areas, are discussed in Chapter 15.
The proportion of children aged 15 years and under being exposed to secondhand smoke in the home has declined from 31% in 1995 to 4% in 2013 (Table 4.5.1).3
Parental smoking, low socioeconomic status and lower level of education attained by parents are consistently identified to be associated with children’s secondhand smoke exposure in the home.5 Among those children who have a parent who smokes, the degree of exposure increases with the number of smokers residing in the home and the heaviness of tobacco smoking among residents.6 Children whose parents have negative attitudes towards secondhand smoke and its health effects are less likely to be exposed.5
Proportion of households with children aged 15 years and under where an adult reports smoking, 1995 to 2013
Source: National Drug Strategy Household Survey detailed report: 2013
Exposure to secondhand smoke in the home is also decreasing for Australian teenagers and adults. The 2013 National Drug Strategy Household Survey reported that 2.8% of people aged 14 years or older were exposed to secondhand smoke in the home,7 a decrease from 6.0% in 2007.
In the NSW Population Health Survey 93.1% of participants aged 16 years and over described their home as being ‘smoke-free’ in 2014 compared with 77.5% in 2002.8
Other Australian surveys indicate that among households with regular smokers, households with older children are less likely to have indoor smoking bans than households with younger children.2, 4, 9 The percentage of reported smokefree homes declines as the age category of the youngest child in the household increases.2, 9 In households with smokers, those with one or more adult non-smokers are more likely to have a smokefree home.2
Secondhand smoke exposure provides additional exposure to nicotine and toxins for smokers. People who smoke and experience secondhand smoke exposure at home have significantly higher cotinine levels when compared with people who smoke who report no exposure to secondhand smoke at home, and this is independent of smoking intensity and other factors.10 In addition, smokefree homes have also been shown to be associated with reduced smoking behaviour among adolescents and adults.11-14 See Chapter 5 for further discussion.
Studies using biomarkers to measure secondhand smoke exposure are consistent with these surveys. A British study examining long-term changes to exposure to secondhand smoke between 1978 and 2000 found that mean serum cotinine levels in non-smoking men decreased seven-fold from 1.36 ng/mL to 0.19 ng/mL. The percentage of men with low levels of cotinine (≤0.7 ng/mL) increased from 27% to 83% over the same time period.15
Disadvantaged populations are more likely to be exposed to secondhand smoke than the general population and this contributes to the greater burden of ill-health.16 People in lower socioeconomic groups and Aboriginal people are more likely to be exposed to secondhand smoke in the home.8, 9, 17 For further discussion on exposure to secondhand smoke in disadvantaged groups, see Chapter 9, Sections 9.1.6 and 9.2.5.
1. Australian Institute of Health and Welfare. 2007 National Drug Strategy Household Survey: Detailed findings. Drug statistics series no. 22, cat. no. PHE 107.Canberra: AIHW, 2008. Available from: http://www.aihw.gov.au/publications/phe/ndshs07-df/ndshs07-df.pdf
2. Borland R, Yong HH, Cummings KM, Hyland A, Anderson S, et al. Determinants and consequences of smoke-free homes: Findings from the international tobacco control (ITC) four country survey. Tobacco Control, 2006; 15(suppl. 3):iii42–iii50. Available from: https://www.ncbi.nlm.nih.gov/pubmed/16754946
3. Australian Institute of Health and Welfare. National Drug Strategy Household Survey detailed report 2013. Drug statistics series no. 28, AIHW cat. no. PHE 183.Canberra: AIHW, 2014. Available from: http://www.aihw.gov.au/WorkArea/DownloadAsset.aspx?id=60129549848
4. Australian Institute of Health and Welfare (AIHW). 2004 National Drug Strategy Household Survey: Detailed findings. AIHW cat. No. PHE 66. Drug Statistics Series No. 16, Canberra: Australian Institute of Health and Welfare, 2005. Available from: http://www.aihw.gov.au/publications/index.cfm/title/10190
5. Orton S, Jones LL, Cooper S, Lewis S, and Coleman T. Predictors of children's secondhand smoke exposure at home: A systematic review and narrative synthesis of the evidence. PLoS One, 2014; 9(11):e112690. Available from: http://www.ncbi.nlm.nih.gov/pubmed/25397875
6. Wang Y, Yang M, Tian L, Huang Z, Chen F, et al. Relationship between caregivers' smoking at home and urinary levels of cotinine in children. International Journal of Environmental Research and Public Health, 2014; 11(12):12499–513. Available from: http://www.ncbi.nlm.nih.gov/pubmed/25469922
7. Australian Institute of Health and Welfare. 2010 National Drug Strategy Household Survey: Survey report. Drug statistics series no. 25, AIHW cat. no. PHE 145.Canberra: AIHW, 2011. Available from: http://www.aihw.gov.au/publication-detail/?id=32212254712&libID=32212254712&tab=2
8. Centre for Epidemiology and Research. Healthstats NSW, 2015, NSW Ministry of Health: Sydney. Available from: http://www.healthstats.nsw.gov.au
9. Abbott J and McCarthy M. Smoking behaviour in homes and around children in victoria: Key findings from the 1998–2008 population surveys. Melbourne, Australia: Centre for Behavioural Research in Cancer, The Cancer Council Victoria, 2009. Available from: http://www.cancervic.org.au/downloads/cbrc_research_papers/09rps40_Smoking_Behaviour_in_homes_and_around_children_in_Victoria.pdf
10. Lindsay RP, Tsoh JY, Sung H-Y, and Max W. Secondhand smoke exposure and serum cotinine levels among current smokers in the USA. Tobacco Control, 2016; 25(2):224-31. Available from: http://tobaccocontrol.bmj.com/content/25/2/224.abstract
11. Wakefield M, Banham D, Martin J, Ruffin R, McCaul K, et al. Restrictions on smoking at home and urinary cotinine levels among children with asthma. American Journal of Preventive Medicine, 2000; 19(3):188–92. Available from: http://www.ncbi.nlm.nih.gov/pubmed/11020596
12. Farkas AJ, Gilpin EA, White MM, and Pierce JP. Association between household and workplace smoking restrictions and adolescent smoking. Journal of the American Medical Association, 2000; 284(6):717–22. Available from: http://jama.ama-assn.org/cgi/content/abstract/284/6/717
13. Emory K, Saquib N, Gilpin EA, and Pierce JP. The association between home smoking restrictions and youth smoking behaviour: A review. Tobacco Control, 2010; 19(6):495-506. Available from: https://www.ncbi.nlm.nih.gov/pubmed/20852326
14. Mills AL, Messer K, Gilpin EA, and Pierce JP. The effect of smoke-free homes on adult smoking behavior: A review. Nicotine & Tobacco Research, 2009; 11(10):1131-41. Available from: https://www.ncbi.nlm.nih.gov/pubmed/19633273
15. Jefferis B, Thomson A, Lennon L, Feyerabend C, Doig M, et al. Changes in environmental tobacco smoke (ets) exposure over a 20-year period: Cross-sectional and longitudinal analyses. Addiction, 2009; 104(3):496–503. Available from: http://eprints.ucl.ac.uk/13887/
16. VicHealth Centre for Tobacco Control. Environmental tobacco smoke in Australia: What is being done and what could be done to reduce exposures. A report to commonwealth department of health & aged care. Melbourne, Australia: VicHealth Centre for Tobacco Control, 2001.
17. Gartner C. 'Reported smoking inside and outside in households with and without dependent children, data from national drug strategy household survey 2001, 2004 and 2007', unpublished data, 2010, University of Queensland: Brisbane.