ARE CHILDREN WITH ASTHMA AFFECTED BY SMOG

Objective: To assess the relationship between atmospheric smog and emergency department attendances in children with asthma. Design: The number of child attendances with acute asthma was calculated retrospectively for each day of the 1989 calendar year. Daily smog data for 1989 were then obtained from the Environment Protection Authority of Victoria, and were related statistically to asthma attendances. Setting: The Emergency Department of the Royal Children's Hospital, Melbourne, which provides primary, secondary and tertiary level health care to the children of Victoria. Patients: All children over two years of age with acute asthma. Main outcome measure: The number of attendances with asthma each day for the 1989 calendar year. Results: Smog alerts (smog days predicted by the Environment Protection Authority) and smog episodes (actual smog days of all types) were not significantly related to asthma attendances. A significant relationship was noted, however, between asthma attendances and days when the airborne particulate index was above the acceptable threshold. No relationship was found between asthma attendances and ozone levels (a marker of photo-oxidant smog), or between any smog index and days of unusually high asthma attendance (asthma epidemic days). All smog variables combined explained only 2.3% of the variance in asthma attendance. Conclusions: Although the overall contribution of smog to asthma attendances in children is small, the correlation between asthma attacks and airborne particles is a hitherto unreported finding in Australia and is potentially of public health importance.