An Integrated and Spatialized Approach to Identify Potentially Overexposed Population : A Case Study of Chlorpyrifos Contamination

Exposure to pesticides is characterized by the multiplicity of exposure routes (food, water, soil, air) related to their presence in all environmental media. First, for a fine characterization of the environmental exposure, it is necessary to gather within the same analysis system a dataset integrating the population behavior and the local contamination of the environmental media at fine resolutions and on large territories. This integration requires a sufficient toolchain to produce or process these data in a rigorous manner, characterize the entire continuum from the source of contamination, transport, and transfer of contaminants in environmental media, and estimate external and internal exposure doses for the general population. The aim of this work is to establish an integrated methodology for the mapping of exposure indicators at fine spatial and temporal resolutions (1 km² and week) directly comparable with individual biomonitoring measurements from French cohorts. To illustrate the approach, we consider the levels of chlorpyrifos among pregnant women in the Picardy region (France). Results provide insights into the identification of areas of potential overexposure and analysis of environmental determinants, elements useful for public health decision to reduce exposure and thus health and environmental impacts. However, the exposure characterization involves uncertainties regarding modeling assumptions and data measurements. Moreover, the efficiency of exposure modeling can be limited by calculation times. To optimize numerical resolution and reduce uncertainties related to knowledge limits and data representativeness, modeling assumptions and tools need to be reconsidered to improve the methodology and allow future developments