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(34-05) GLOBOX: a spatially differentiated global fate and exposure model. Wegener Sleeswijk, Anneke*,1, 1 CML, P.O. Box 9518, Leiden, The Netherlands ABSTRACT- GLOBOX is a model under construction for the calculation of spatially differentiated LCA characterization factors on a global scale. GLOBOX consists of three main modules: an impact-category independent fate module, a human-exposure module, applicable to all impact categories that are related to human exposure to chemicals, and an effect module, which contains effect-related parameters for every separate impact category. The fate and exposure modules are differentiated on the level of separate countries and oceans, which means that there are about 250 regions. Each country or ocean has its own set of homogeneous compartments, and all countries and oceans are interconnected by atmospheric and aquatic flows. Oceanic water bodies are handled as a two-compartment system: the surface mixed layer and the deep ocean. Multimedia transport and degradation calculations are largely based on the EUSES multimedia model SimpleBox 2.0, and are supplemented by specific equations to account for advective air and water transport between different countries or oceans. Metal-specific equations are added to account for speciation in fresh and marine surface water. Empirical estimates of individual sedimentation rates in the ocean surface mixed layer are included for a number of important metals. Distribution parameters for multimedia transport equations are differentiated per country or ocean with respect to climatic features, water coverage, and land use. All distribution equations are solved simultaneously by matrix inversion (matrix dimension 3000×3000), allowing for the calculation of global-scale multimedia transport. Human exposure calculations are based on intake by food and drinking water consumption and inhalation of the exposed population. Exposure parameters are differentiated per country with respect to population density, estimated mean body weight, consumption pattern, fraction of drinking water derived from surface water and groundwater, respectively, and fraction of drinking water that has been purified. GLOBOX requires only substance-specific input of physicochemical and toxicity data to calculate specific human and ecological toxicity characterization factors for unit emissions to any compartment in any country of the world. Key words: fate modelling, exposure modelling, spatial differentiation, global multimedia model |
