B. RESULTS OF PERSONNEL MONITORING 1. 1970-1974: During this period both urine and gamma spectrographic analyses showed body burdens of 137¢s and 9[sr in people living at Bikini to be well below the maximum permissible body burdens and about & of the levels of the Rongelap people who were also measured during that period. The annual dose to the bone marrow in the Bikini people was estimated to be about 20-22 mrad from the internal exposure. This indicated that they had largely been subsisting on food furnished from the TT, since availability of locally grown foods was minimal. maturity. Coconuts, breadfruit and pandanus had not yet reached At the time of the visits of our team to Bikini, the people were informed about our findings. They were told of the presence of radioactive Sr and Cs and were advised not to eat locally grown foods. They were also advised about the presence of low levels of Pu in their urine in 1975. At a meeting with the people in 1977 they admitted they were eating some foods grown locally. During this period we were able to report to the people that levels of radiation exposure on Bikini were comparable to that Of people living in some other areas in the world, such as those living at high altitudes (e.g. Denver, Colorado), and that no detectible effects were noted in people who lived in these areas. 2. The Plutonium Finding: In 1975 the Health and Safety Laboratory reported that urine samples from the Bikini people showed the presence of low levels of ’ Pu. It was known that low levels of Pu were present on Bikini in the soil, catchment water, plants, etc. Since the levels reported were at the lower range of detection (0.009 + 0.002 pci/liter) and the standard error of counting at these levels was large, there was some doubt that the measurements were significant. Contamination of the urine samples was considered a possibility. A calculation of body burden at this level of Pu excretion revealed that the isotope could not exceed 10% of the MPBB. Although levels are very Low, diet seems to be the most probable source of Pu in urine. Samples of soil on Bikini had shown Pu to be less than the 40 pCi/g established as the upper level for the Enewetak survey. The Transuranium Task Group (advisory group to the AEC) was asked to review the Bikini data. Dr. Bair, Chairman of the Committee, reported that, "if taken at face value, the risk [to the people living on Bikini] would be very small". Recent samples of Bikini urines (1977-1978) analyzed at the Los Alamos Laboratory, have revealed very low levels of Pu. Several months ago we arranged for the Health Aide from Bikini, who was in Washington, DC, for Congressional Hearings, to have Americium-241 counts done in a special facility at NYU by Dr. N. Cohen. (Americium is known to be present with Pu.) The results were negative for Americium and presumably also for Pu. Thus the low ievels of Pu present in the people are probably not radiologically significant - 3 co -4- (3219