viscera. If the internal, body burdens of transuranic nuclides are accumulated by the fish through the gut, then it could be concluded that in most cases there is a discrimination against @4!Am relative to 239+240py in different tissues. The radionuclides 242cm, 243cm, and 244cm have been detected in some fish tissues from Bikini. Concentrations of 43cm and 244cm are a few percent of the 239+240py concentrations and 242cm is less than 1% of the 239+240py levels in the entire fish. 25 years after The detection of 242cm (tj/2 = 163 d), approximately the end of testing, indicat®s the presence of a parent radionuclide, 242MAm, in the environment. OTHER RADIONUCLIDES IN FISH Concentrations of '13mMcg and naturally occurring 2!0pu, 210p0, and 2108; determined in fish samples are listed in the Appendix. Discussions of the concentrations and significance of these radionuclides at Bikini Atol] have been presented in the literature®-8 and will not be repeated here. RADIONUCLIDES IN INVERTEBRATES Edible species of clams and a few other invertebrates were collected by hand (free diving) in shallow areas of the lagoon. sometimes Collections for radionuclide analyses were terminated in 1980 for fear of depleting this valuable food resource at the atoll]. Radiological concentration data from analysis of these few samples are included here for reference. The clams were weighed, measured (total length), and dissected. muscles, mantle plus siphon, kidney, Adductor and remaining viscera that included © gills, gonad, stomach, intestine and contents, crystalline style, heart, and nervous system were removed for analysis. Tissue samples were dried in ovens at 90°C to constant dry weight and dry ashed in muffle furnaces at 450°C for approximately ~ invertebrates 72 were hours. Radionuclide determined by the concentrations same procedures in tissues used to of measure concentrations in fish tissues (see Sample Processing and Analysis, page 7). Collection information and radionuclide concentrations are shown in Tables A-15 and A-16 of the Appendix. Too few samples were collected and analyzed to develop trends or meaningful relationships with the concentration data. However, it is noted 5000519 irae | a]