Mini-symposium: Pollutants and respiratory health in children
Indoor air quality and respiratory health of children

https://doi.org/10.1016/j.prrv.2007.08.007Get rights and content

Summary

Indoor air pollution (IAP) is an important environmental health issue in developing countries and is a major contributor to mortality and morbidity from acute lower respiratory illness in children. In developed countries, IAP in homes is not nearly as severe as it can be in developing countries; however, evidence suggests that it does contribute significantly to the risk of adverse respiratory health in children. Children spend the majority of their time indoors, mostly at home. Homes are built so that air exchange between the indoor and outdoor environments is minimised and there is a large range of pollution emission sources inside. For many pollutants, indoor concentrations regularly exceed those outdoors. Although there has been considerable interest in the health effects of IAP, questions still remain regarding the role of IAP in the exacerbation and/or development of respiratory disease. Prospective, longitudinal studies are required to better clarify the contribution of IAP to the respiratory health of children.

Section snippets

Why indoor air pollution?

Outdoor air pollution has long been considered a considerable risk for human health, particularly since major air pollution events such as the London smog of the early 1950s. Although outdoor air pollution, particularly pollution associated with vehicle exhausts, remains a concern,2 there has been a growing recognition that IAP is of equal or greater significance to human health.3 Reasons for this include: the amount of time people spend indoors; the wide and varied range of indoor emission

IAP and children's respiratory health

Important indoor pollutants were identified in Table 1. Each of these has been associated with adverse respiratory health in children, although in many cases the data remain equivocal. Although indoor biological pollutants are an important contributor to respiratory disease in children,14 the remainder of this review will focus on the more ubiquitous chemical pollutants in homes.

Does IAP cause asthma?

Indoor allergens are considered by some, but not all, to be an important cause of asthma and allergy in children.14 In contrast, indoor chemical air pollutants are considered more likely to be, at worst, a trigger for asthmatic symptoms. A causative role for IAP in asthma is difficult to demonstrate, however, evidence is emerging that suggests some air pollutants may indeed contribute to the development of asthma and other allergic diseases in children. For example, exposure of pregnant women

Conclusion

In 2000, the US Institute of Medicine published a book on asthma and indoor air exposures,61 which concluded that for asthma exacerbations there was: sufficient evidence of a causal relationship with ETS; sufficient evidence of an association with NO2; and suggestive evidence of an association with formaldehyde. For asthma initiation, the authors concluded that there was no evidence of a causal relationship with any of the chemical pollutants although there was suggestive evidence of an

Final remarks

Children spend the majority of their time indoors at home and this is unlikely to change in the near future. Homes are still built to reduce air ‘leakage’ and increase energy efficiency. Again this remains a dominant factor in building design. The exchange between indoor and outdoor air, therefore, relies on the opening of external windows and doors. However, there is an increased reliance on mechanical means to control indoor climate, reducing the need for active ventilation. Some form of

References (65)

  • H. Bisgaard

    The Copenhagen Prospective Study on Asthma in Childhood (COPSAC): design, rationale, and baseline data from a longitudinal birth cohort study

    Ann Allergy Asthma Immunol

    (2004)
  • M. Kabesch

    Gene by environment interactions and the development of asthma and allergy

    Toxicol Lett

    (2006)
  • World Health Organisation

    The World Health Report 2002 - Reducing risks, promoting healthy life

    (2002)
  • J. Schwartz

    Air pollution and children's health

    Pediatr

    (2004)
  • P.T. Harrison

    Health impacts of indoor air pollution

    Chem Indust

    (1997)
  • A. Farrow et al.

    Time spent in the home by different family members

    Environ Technol

    (1997)
  • J.A. Wiley et al.

    Study of Children's Activity Patterns

    (1991)
  • Department of Environment and Heritage

    Unflued Gas Appliances and Air Quality in Australian Homes

    (2004)
  • J.L. Adgate et al.

    Outdoor, indoor, and personal exposure to VOCs in children

    Environ Health Perspect

    (2004)
  • J. Jurvelin et al.

    Personal exposure levels and microenvironmental concentrations of formaldehyde and acetaldehyde in the Helsinki metropolitan area, Finland

    J Air Waste Manage Assoc

    (2001)
  • L. Wallace

    Indoor particles: a review

    J Air Waste Manage Assoc

    (1996)
  • L.C. Oliver et al.

    The indoor air we breathe

    Public Health Reports

    (1998)
  • C. Howard-Reed et al.

    Use of a continuous nephelometer to measure personal exposure to particles during the U.S. Environmental Protection Agency Baltimore and Fresno Panel studies

    J Air Waste Manag Assoc

    (2000)
  • United States Environmental Protection Agency

    Respiratory health effects of passive smoking

    (1993)
  • I.B. Tager et al.

    Maternal smoking during pregnancy. Effects on lung function during the first 18 months of life

    Am J Respir Crit Care Med

    (1995)
  • P.S. Noakes et al.

    Maternal smoking is associated with impaired neonatal toll-like-receptor-mediated immune responses

    Eur Respir J

    (2006)
  • D.P. Strachan et al.

    Health effects of passive smoking. 6. Parental smoking and childhood asthma: longitudinal and case-control studies

    Thorax

    (1998)
  • S. Soliman et al.

    Decrease in the prevalence of environmental tobacco smoke exposure in the home during the 1990s in families with children

    Am J Public Health

    (2004)
  • G.E. Matt et al.

    Households contaminated by environmental tobacco smoke: sources of infant exposures

    Tob Control

    (2004)
  • R. Bascom

    Health effects of outdoor air pollution

    Am J Respir Crit Care Med

    (1996)
  • M.H. Garrett et al.

    Respiratory symptoms in children and indoor exposure to nitrogen dioxide and gas stoves

    Am J Respir Crit Care Med

    (1998)
  • G. de Bilderling et al.

    Gas cooking and smoking habits and the risk of childhood and adolescent wheeze

    Am J Epidemiol

    (2005)
  • Cited by (0)

    View full text