Path to healthier air

Briefly, the approach relies on knowing 1. for each pollutant, concentration response functions that quantify the percent change in a particular health outcome per unit change in ambient concentration of that air pollutant; 2. the prevalence of each health outcome of interest in Toronto; 3. the ambient concentration of each pollutant; 4. the number of people at risk (eg., the population of Toronto [...] The burden of illness is then calculated for each pollutant by multiplying the concentration response function (in the format of percent change in a particular outcome per unit of exposure) with the concentration of the associated pollutant in Toronto, and then by the prevalence of that outcome in Toronto with and the population at risk. [...] To provide a sense of the magnitude of these other health impacts it may be useful to scale up from previous estimates in a 2007 report estimating the burden of illness from air pollution related to traffic in the City (TPH, 2007). [...] A comparison of the estimates of 440 premature deaths and 1,700 hospitalizations attributable to air pollution from traffic to the current estimates of 280 premature deaths and 1,090 hospitalizations from traffic sources suggests that a scaling factor of 0.64 could be applied to the other health outcomes to derive an estimate of their magnitude. [...] Figure 1: Pyramid of Health Effects from Traffic-Related Air Pollution Pollutants Associated With the Greatest Health Impacts Five air pollutants were considered in the calculation of the burden of illness from air pollution in Toronto.