Acute effects of low levels of ambient ozone on peak expiratory flow rate in a cohort of Australian children

Int J Epidemiol. 2000 Jun;29(3):549-57.


Background: We enrolled a cohort of primary schoolchildren with a history of wheeze (n = 148) in an 11-month longitudinal study to examine the relationship between ambient ozone concentrations and peak expiratory flow rate.

Methods: Enrolled children recorded peak expiratory flow rates (PEFR) twice daily. We obtained air pollution, meteorological and pollen data. In all, 125 children remained in the final analysis.

Results: We found a significant negative association between daily mean deviation in PEFR and same-day mean daytime ozone concentration (beta-coefficient = 0.88; P = 0.04) after adjusting for co-pollutants, time trend, meteorological variables, pollen count and ALTERNARIA: count. The association was stronger in a subgroup of children with bronchial hyperreactivity and a doctor diagnosis of asthma (beta-coefficient = -2.61; P = 0.001). There was no significant association between PEFR and same-day daily daytime maximum ozone concentration. We also demonstrated a dose-response relationship with mean daytime ozone concentration.

Conclusions: Moderate levels of ambient ozone have an adverse health effect on children with a history of wheezing, and this effect is larger in children with bronchial hyperreactivity and a doctor diagnosis of asthma.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Air Pollutants / adverse effects*
  • Asthma / etiology*
  • Child
  • Cross-Sectional Studies
  • Female
  • Humans
  • Longitudinal Studies
  • Male
  • Oxidants, Photochemical / adverse effects*
  • Ozone / adverse effects*
  • Peak Expiratory Flow Rate
  • Respiratory Sounds / etiology


  • Air Pollutants
  • Oxidants, Photochemical
  • Ozone