Associations between Respiratory Health Outcomes and Coal Mine Fire PM2.5 Smoke Exposure: A Cross-Sectional Study.

In 2014, wildfires ignited a fire in the Morwell open cut coal mine, Australia, which burned for six weeks. This study examined associations between self-reported respiratory outcomes in adults and mine fire-related PM2.5 smoke exposure. Self-reported data were collected as part of the Hazelwood Health Study Adult Survey. Eligible participants were adult residents of Morwell. Mine fire-related PM2.5 concentrations were provided by the Commonwealth Scientific and Industrial Research Organisation Oceans & Atmosphere Flagship. Personalised mean 24-h and peak 12-h mine fire-related PM2.5 exposures were estimated for each participant. Data were analysed by multivariate logistic regression. There was some evidence of an association between respiratory outcomes and mine fire PM2.5 exposure. Chronic cough was associated with an odds ratio (OR) of 1.13 (95% confidence interval 1.03 to 1.23) per 10 μg/m3 increment in mean PM2.5 and 1.07 (1.02 to 1.12) per 100 μg/m3 increment in peak PM2.5. Current wheeze was associated with peak PM2.5, OR = 1.06 (1.02 to 1.11) and chronic phlegm with mean PM2.5 OR = 1.10 (1.00 to 1.20). Coal mine PM2.5 smoke exposure was associated with increased odds of experiencing cough, phlegm and wheeze. Males, participants 18-64 years, and those residing in homes constructed from non-brick/concrete materials or homes with tin/metal roofs had higher estimated ORs. These findings contribute to the formation of public health policy responses.