Relationships between environmental factors and lung function of asthmaticsubjects in South East Queensland, Australia

Few panel studies have investigated the relationships between air pollutant s and air spora and lung function change in asthmatic subjects. This articl e examines the association of outdoor air pollutant concentrations and air spora with the decrease in lung Sanction (measured by morning-peak expirato ry flow) of two groups of asthmatic subjects in the subtropical environment of South East Queensland, Australia. Lung-function responses were stratifi ed by age, allergy status, and location, and seasonal effects were examined . Allergy status and age were found to be important, with air pollutants su ch as ozone and particles associated with decreases in lung function in all ergic individuals older than 15 years. Fungal spore counts were strongly as sociated with a decrease in lung function in allergic adults, especially in those over 54 years, only in seasons when these air spora peak. Analysis f or the entire study period indicates that the effect of ozone on peak expir atory flow in the allergic group can sometimes be confounded by air spora e ffects, indicating that in a subtropical climate the impact of ozone on ast hma severity can be accurately estimated only when the confounding effects of air spora are included.