A method for calculation of dose per unit concentration values for aquatic biota within FASSET

摘要

A dose per unit concentration database has been generated for application to ecosystem assessments within the FASSET framework. Organisms are represented by ellipsoids of appropriate dimensions, and the proportion of radiation absorbed within the organisms is calculated using a numerical method implemented in a series of spreadsheet-based programs. Energy-dependent absorbed fraction functions were derived for calculating the total dose per unit concentration of radionuclides present in biota or their surrounding medium. All radionuclides and reference organism dimensions defined within FASSET for marine and freshwater ecosystems are included. With regard to the applicability of the method, it is assumed that differences in density between the organism and the surrounding environmental media may be ignored; for the aquatic environment this is an extremely good approximation.