71 in adults and 22 nCi in children, about 6 and 11% respectively of the maximum permissiblelifetime body-burden levels for the population at large, ie., local nuclear testing program and also from worldwide fallout, and to be concentrated by marine life, particularly fish. The estimated body burdens for the Marshallese tested (Table 43) are higher than those found for Japanese bombsurvivors and “othe ICRP value.!®® Analyses of bone samples from several autopsies during the past 20 years gave estimated 9°Sr body burdenssimular to those obtained from urinalysis (see Figure 37). 137Cs body burdens also reached their peak in about 1965, at nearly 0.7 pCi (23% of the permissible level for the general population). The body burdensof the Utirik people were considerably below those of the Rongelapese. Table 42 showsthat the estimated bone marrow doses of Rongelap people of the maximum permissible levels for non-occupationally exposed individuals estimated with the total body as the critical organ. The values are slightly higher in females than in males, andsignificantly higher in older persons. *5Fe emits photons of very low energy, and, sinceit is incorporated into the hemoglobin ofthe red cells, ic results in reduced by 1974, and presents data also for Uunk blood samples from the 1974 surveyare also being analyzed for 95Fe. from internal and external sources (both natural and man-maderadioactivity) were considerably and Bikini.* The coconut crab was banned from thediet on Rongelap becauseofits high level of radioactivity, but about 2 years ago the ban waslifted on the southern islands of the atoll because the radioactivity had decreased sufficiently (see Table 40). B. °5Fe BODY BURDENS IN RONGELAPESE In 1971 blood samples from 62 Rongelapresidents were analvyzed** for °°Fe, and their body burdens were estimated by the method of Beasley et al.170 55Fe was known to be present in the Marshall Islandsin fairly high levels as a result of the *Mr. R. Fairchild at BNL calculated the bone marrow dose for the 1974 data. **The °°Fe analyses were carried out by T.M. Beaslev and E.E. Held at the University of Washington Schoolof Fisheries, Seattle. Table 43 Average Body Burdens of 55Fe in Rongelapese, 1971170 Males Age No.of samples 16-20 21-31 32-42 43-53 8 4 5 2 >64 3 54-64 Females 16-20 21-31 32-42 43-53 54-64 >64 6 6 212 5 7 2 2 Body burden, pCi 0.31 0.33 0.52 0.58 0.53 0.48 0.23 0.34 0.33 0.66 0.57 0.66 for others tested, but they are not more than “00 relatively little irradiation of nucleated cells. Some C. PERSONNEL MONITORING AT BIKINI In 1946, before Operation Crossroads, theresidents were evacuated from Bikini. After stays at Rongerik and at Kwajalein which proved unsatisfactory, they were relocated on Kili Island in the southern Marshalls, which also proved unsatisfactory. The Eniwetok people were relocated at Ujelang Atoll, to the west, after their evacuation. After the 1958 moratorium on atmospheric nuclear testing, numerous radiological surveys were done on Bikini and later on Eniwetok Atoll.17!-174 In 1967 the principal isotopes contributing to the gammaradiation field on Bikini and Eneu Islands were 137s, 69Co, 125Sb, and !55Eu; slight amounts of Pu werealso found. Considerable variation was seen in the contamination of individualislands comprising theatolls of Bikini and Eniwetok since different tests had been conducted on various ones. The contamination of Rongelap and Utirik was more uniform, being due largely to fallout from a single detonation, Bravo. In 1968 an ad hoc committee reviewed the survey results for Bikini and decided that Eneu and Bikini Islands were safe for habitation, with cer- tain measures recommendedto reduce exposure (see Appendix 13). In 1969 about 30 people started work on Bikini Atoll (living on Eneu), and in 1971 several Bikini families moved back to Bikini Island itself, which now has about 50 Bikini people plus a few administrators and construction workers. Annual monitoring of personnel has been carried out since 1969. In 1974 radiochemical analyses were done on urine (see Table 37 and Appendix 12) and other samples, whole-body gamma spectroscopy was carried out on personnelliving on