Risk of cardiopulmonary ambulance attendance associated with sub-daily exposures to forest fire smoke
To quantify the population risk of respiratory and cardiovascular health outcomes associated with sub-daily exposures to fine particulate matter (PM2.5) associated with forest fire smoke. Study results will address two gaps related to forest fire smoke and public health: (1) the health risks associated with transient exposures that last for less than one day, and (2) the health risks associated with peak exposures within smoky days.
More specific objectives:
1) To generate hourly smoke maps for all populated areas of British Columbia (BC) for all fire seasons from 2003 through 2015.
2) To obtain the time and location of all ambulance dispatches across BC for the same period.
3) To geocode all dispatch locations, and to assign exposure variables to each dispatch for the 48 hours prior to the call.
4) To use a case-crossover design to evaluate the effects of different smoke exposure windows ranging from 1-hour to 48-hours for the purpose of understanding the risks of sub-daily exposures compared with those of daily exposures.
5) To disseminate study results to public health authorities across Canada via the Guidance for Public Health Decision Making During Wildfire Smoke Events, which has been developed and maintained by the BC Centre for Disease Control (BCCDC).
1) An empirical model that combines hourly satellite, air quality, and meteorological data can produce hourly estimates of forest fire smoke-related PM2.5 that are comparable with measured concentrations for all populated areas in BC
2) Exposure to increased concentrations smoke-related PM2.5 for periods shorter than one day (i.e. sub-daily exposure) is associated with increased risk of respiratory and cardiovascular events attended by ambulance services, and that the lag time between exposure and response can be characterized in hours.