ASSOCIATION OF SPATIAL-DISTRIBUTION OF CHILDHOOD RESPIRATORY MORBIDITY WITH ENVIRONMENTAL DUST POLLUTION

The objective of this study was to investigate the spatial distributio n of respiratory morbidity and asthma in children in relation to high levels of airborne dust pollution. A cross-sectional survey of 2035 ch ildren (aged 5-11 yr) by parent-completed questionnaire, with concurre nt monitoring of dust deposition rates in the vicinity of children's h omes, was performed in 15 primary schools (5 in each of 3 areas of Mer seyside). The main outcome measures were (I) doctor-diagnosed asthma, (2) parent-reported respiratory symptoms of recent excess cough, wheez e, and breathlessness, and (3) school absenteeism due to respiratory i ll health. Proximity to the source of dust pollution was associated wi th increased prevalence of excess cough, breathlessness, school absenc e due to respiratory ill health, and doctor-diagnosed asthma, after ad justing for a range of socioeconomic, environmental, and other confoun ding factors. The adjusted odds for excess cough and breathlessness fo r children living within 2 km of the source (dock area) are estimated to be almost twice those for children living more than 2 km away: exce ss cough 1.9 (95% CI 1.4-2.6); breathlessness 1.9 (1.3-2.7); school ab sence 1.5 (1.2-1.9); and doctor-diagnosed asthma 1.5 (1.1-2.0). Excess cough was significantly associated with the mean annual dust depositi on recorded in the vicinity of the child's home. The adjusted odds rat io for excess cough corresponding to an increase in mean annual dust d eposition of 50 mg/m(2)/d was 3.1 (95% CI 1.1-8.2). These results sugg est that airborne dust was associated with respiratory morbidity in th ese children, which could relate to the high prevalence of childhood d octor-diagnosed asthma in this community.