TPS 684: Long-term health effects of air pollutants 1, Exhibition Hall, Ground floor, August 26, 2019, 3:00 PM - 4:30 PM
In 2014 a coal mine fire exposed an Australian community to high smoke concentrations over six weeks. The longer-term health impacts of such exposure in utero and in early childhood are unknown. Existing evidence suggests that increased risks of respiratory disease and allergies are plausible. We evaluated the association between early life coal mine fire smoke exposure and parent-reported indicators of respiratory and atopic illness 2-4 years later.
Methods: This prospective cohort study enrolled children in three exposure groups: in utero, early childhood (0-2 years of age) and unexposed (conceived after the fire). We estimated individual average and peak fire-attributable PM2.5 exposures using modelled 12-hourly air quality and time-activity data. Parents reported symptoms, medication use, and doctor attendances relating to respiratory and atopic illness by monthly diary for 29 months 2-4 years after the fire. We used modified mixed-effects Poisson models, adjusted for important confounders including age, season, and tobacco smoke exposure, to separately examine associations between outcomes and exposure to PM2.5 in utero and in early childhood.
Results: The in utero analysis included 2678 monthly diaries from 160 children, while the early childhood analysis included 3290 diaries from 210 children. Both average and peak PM2.5 exposure in utero were associated with increased reports of multiple outcomes. An increase in average PM2.5 of 10µg/m3 was associated with increased reports of runny nose and/or cough (RR 1.09; 95%CI 1.02-1.17), wheeze (RR 1.56; 95%CI 1.18-2.07), seeking health professional advice (RR 1.17; 95%CI 1.06-1.29), and doctor diagnosis of ‘upper respiratory tract infection, cold or flu’ (RR 1.35; 95%CI 1.14-1.60). Associations with early childhood exposures were less consistent.
Conclusion: Findings suggest children exposed to coal mine fire smoke in utero had a higher risk of acute respiratory infections 2-4 years later. These findings require confirmation in other studies and settings.