Multi-Region Multimedia Chemical Fate and Exposure Model for use in Life Cycle Assessment in Japan

This presentation provides an overview of the prototype for a multi-region multimedia fate and exposure model to support Japan's National Life Cycle Assessment (LCA) initiative.  Multi-region multimedia models provide a solution to take both spatial resolution, as well as intermedia transport, into account.  The model consists of modules for the calculation of the long-term fate and exposure of chemicals.  The multimedia fate module takes spatial variation, advective transport, intermedia exchange and degradation processes into account.  Fate processes are considered for hydrologically-defined surface water areas (watersheds), coastal waters, sediments, air zones, urban areas, soils and vegetation.  The human exposure module includes consideration of the spatial variation of population density, which is required to later estimate population-based characterization factors (marginal effect of a chemical emission of 1 kg hr-1) in LCA.  Both region-specific and generic characterisation factors are developed.  The generic factors can be used with LCA inventory (emissions) data in the absence of release location information.  An estimate of the uncertainty associated with the lack of release location information is provided.