C-C1-02: Creating a GIS Infrastructure to Evaluate Air Quality's Effect on Health Outcomes

Abstract

Background and Aims: Air pollution exposure is a complex and heterogeneous condition. The association of air pollution with disease is consistently established in many epidemiological studies. This creates a need for an infrastructure to measure both air pollution levels and health outcomes geospatially. Methods: As part of the North American Public Health Institute, we developed a multidisciplinary, international research team encompassing Windsor, Ontario, Canada and Detroit, Michigan, USA. While this geographic region consists of a single air-shed it exhibits different socioeconomic conditions and health delivery systems. We deployed 100 active and/or passive pollution samplers across this common air-shed based on U.S. Environmental Protection Agency guidelines for ambient air monitoring to determine levels of gaseous (i.e., NO2, SO2), volatile and particulate pollutants at a resolution greater than what is currently available. We are collecting asthma-related health outcomes for the populations residing within this region using emergency room, clinic, and hospital encounters from American and Canadian health care providers. Utilizing global positioning satellite for pollution sampler allocation and geocoding technique for patient address location, we created a complex mappable system to relate air pollution components and levels to health outcomes. Results: Air pollution levels can be linked to asthma events by several mechanisms. The first step is to use direct measurement value of the closest sensor by creating Voronoi polygons and mapping the asthma events to that geographic area. Associations between pollution level and asthma exacerbation can be examined between these data set. Models of the pollution levels using land use regression can increase the resolution beyond the point values. Longitude/latitude coordinates can be mapped to a pollution level in the surface generated by the model. Conclusion: Establishing a geospatial information system (GIS) integrated database with both pollution measurements and health outcomes creates a comprehensive resource. This infrastructure is flexible enough to investigate the effects of air pollution on many diseases, such as respiratory and cardiovascular disease, by physical and mathematic modeling. We can also compare health outcomes by health delivery system.