Assessing population exposure using multimedia exposure model and spatial analysis techniques

International audienceAssessing population exposure using multimedia exposure model and spatial analysis techniquesKeywords: Model, multimedia, exposure, indicator Analyzing the relationship between environment and health has become a major preoccupation for public health as evidenced by the emergence of the second French national plan for health and environment. Two main axes have been retained: - To identify and manage geographic areas where hotspot exposures are suspected to generate a potential risk to human health; - To reduce exposure inequalities. The explicit objective of this project is to develop a spatial multimedia exposure model able to detect vulnerable populations and to analyze exposure determinants. A multimedia exposure model was developed by INERIS to assess the transfer of Chemicals Of Concerns (COC) from the environment (air, water, soil, food chain) to human exposure through inhalation and ingestion pathways. This project adds a spatial dimension by linking a GIS (Geographic Information System) to the model. Tools were developed using modeling, spatial analysis and geostatistic methods to build and discretize interesting variables and indicators from different supports and resolutions on a 1 km2 regular grid within France. For example, surface soil concentrations were estimated by developing a kriging method able to integrate surface and point spatial supports. We used distance from river and surface water quality measurements to build a proxy for intake by fish ingestion. Downscaling method was developed to map population density at a fine scale using census and land cover data. Eulerian atmospheric dispersion model (CHIMERE) enabled to describe atmospheric deposition and concentrations. Spatial data were used to implement environmental and population characteristics into the multimedia exposure model. The purpose of this work is to present data treatment and model development based on the example of cadmium. Simulation results enable to identify pollutant sources, determinants of exposure, and vulnerable populations. Environmental and exposure datasets will be integrated in the French coordinated, integrated environment and health (spatial) GIS-based platform to map and analyze environmental inequalities