Urban Air and Emergency Department Visits in Toronto, Canada

This study examines the relationship between short-term exposure to ambient air pollution and the onset of human health conditions in Toronto, Canada. Urban air quality is influenced by various pollutants, many of which pose risks to human health. This research specifically investigates the acute effects of these pollutants in Toronto, with health outcomes measured by emergency department visits. To assess relative risks, statistical models were developed for 8 air pollutants and 18 demographic and seasonal strata (defined by sex, age, and season). Health outcomes were categorized into 12 disease groups based on the International Classification of Diseases, 10th Revision (ICD-10). The results were compiled into matrices, each containing 18 rows (strata) and 15 columns (lags) for each of the 8 pollutants and 12 health categories classified by ICD-10 codes. Estimated coefficients and their standard errors were analyzed to interpret the associations. A series of graphs were generated to visualize the effects of selected air pollutants on health. The findings highlight a significant association between ambient ozone levels and respiratory diseases (ICD-10 codes: J00–J99). Additionally, correlations were observed for certain infectious and parasitic diseases (ICD-10 codes: A00–B99). These results contribute to the growing evidence on the health impacts of urban air pollution.