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Abstract: Background: Although ambient air pollution exposure has been linked with poor health in many parts of the world, no previous study has investigated the effect on morbidity in the city of Adelaide, South Australia. Objective: To explore the association between particulate matter (PM) and hospitalisations, including respiratory and cardiovascular admissions in Adelaide, South Australia. Methods: For the study period September 2001 to October 2007, daily counts of all-cause, cardiovascular and respiratory hospital admissions were collected, as well as daily air quality data including concentrations of particulates, ozone and nitrogen dioxide. Visibility codes for present weather conditions identified days when airborne dust or smoke was observed. The associations between PM and hospitalisations were estimated using time-stratified case-crossover analyses controlling for covariates including temperature, relative humidity, other pollutants, day of the week and public holidays. Results: Mean PM10 concentrations were higher in the warm season, whereas PM2.5 concentrations were higher in the cool season. Hospital admissions were associated with PM10 in the cool season and with PM2.5 in both seasons. No significant effect of PM on all-age respiratory admissions was detected, however cardiovascular admissions were associated with both PM2.5 and PM10 in the cool season with the highest effects for PM2.5 (4.48%, 95% CI: 0.74%, 8.36% increase per 10μg/m3 increase in PM2.5). Conclusion: These findings suggest that despite the city''s relatively low levels of air pollution, PM concentrations are associated with increases in morbidity in Adelaide. Further studies are needed to investigate the sources of PM which may be contributing to the higher cool season effects. [Copyright &y& Elsevier]

Abstract: Background: Climate change projections have highlighted the need for public health planning for extreme heat. In Adelaide, South Australia, hot weather is characteristic of summer and heatwaves can have a significant health burden. This study examines the heat thresholds and temperature relationships for mortality and morbidity outcomes in Adelaide. Methods: Daily maximum and minimum temperatures, daily mortality, ambulance call-outs, emergency department (ED) presentations and hospital admissions were obtained for Adelaide, between 1993 and 2009. Heat thresholds for health outcomes were estimated using an observed/expected analysis. Generalized estimating equations were used to estimate the percentage increase in mortality and morbidity outcomes above the threshold temperatures, with adjustment for the effects of ozone (O3) and particulate matter<10μm in mass median aerodynamic diameter (PM10). Effect estimates are reported as incidence rate ratios (IRRs). Results: Heat-related mortality and morbidity become apparent above maximum and minimum temperature thresholds of 30°C and 16°C for mortality; 26°C and 18°C for ambulance call-outs; and 34°C and 22°C for heat-related ED presentations. Most health outcomes showed a positive relationship with daily temperatures over thresholds. When adjusted for air pollutants, a 10°C increase in maximum temperature was associated with a 4.9% increase in daily ambulance call-outs (IRR 1.049; 95% CI 1.027–1.072), and a 3.4% increase in mental health related hospital admissions (IRR 1.034; 95% CI 1.009–1.059) for the all-age population. Heat-related ED presentations increased over 6-fold per 10°C increase in maximum temperature. Daily temperatures were also associated with all-cause and mental health related ED presentations. Associations between temperature over thresholds and daily mortality and renal hospital admissions were not significant when adjusted for ozone and PM10; however at extreme temperatures mortality increased significantly with increasing heat duration. Conclusions: Heat-attributable mortality and morbidity are associated with elevated summer temperatures in Adelaide, particularly ambulance call-outs, mental health and heat-related illness. [Copyright &y& Elsevier]