Cardiorespiratory effects of ambient particulates, controlled human exposures to concentrated ambient PM¦2.5 (CAP) alone and with added ozone

grantor: University of TorontoEpidemiological studies suggest that there may be adverse human health effects associated with exposure to ambient fine particles (PM2.5). In preliminary studies, we examined the health effects of concentrated ambient PM2.5 (CAP) in downtown Toronto using the Harvard ambient particle concentrator. In the initial study, four young, healthy volunteers were each exposed to filtered air (FA), and CAP levels ranging from 23 to 124 [mu]g/m 3 for two hours. In the second study, four young, asthmatic individuals were exposed to FA, up to 130 [mu]g/m3 CAP and/or 80 ppb ozone. Response measures included inflammatory cells, blood coagulation factors and cardiac effects. Using the parameters examined in these pilot studies, we were not able to demonstrate that the exposure to up to 130 [mu]g/m 3 CAP alone or with 80 ppb ozone has acute health effects in young healthy or asthmatic individuals. The statistical significance of this was not assessed due to the small number of subjects in these pilot safety studies. Additional research with more subjects will be required to further examine the cardiorespiratory effects of PM2.5.M.Sc