and committed effective dose equivalent were estimated and given in Table 4 for each of these nuclides as well. The standard deviation for the fifty-year cumulated intake for each nuclide does not include the deviations due to the variation or uncertainty of biological removal rate constants, radioactive decay constants or the fraction of an element eliminated via the urine pathway. These variations plus the varia- tion of specific absorbed fraction of photon energy would introduce even greater standard deviation than that indicated in Table 4 for the estimate of committed effective dose equivalent. External Radiation Exposure External exposure-rate history curves for periods following resettlement are plotted on Figs. 7 and 8. These exposure rates were many times less than the March 1, 1954 exposure rates 12 hours after detonation of BRAVO. time they were estimated to average 2.3x10° nc kg At that 1 nl (8.9 R nt) for Rongelap Island, Rongelap Atoll and 8.9x10° nc kg! mn! (0.34 Rh!) for Utirik Island, Utirik Atoll (Le80b). These estimates were extrapolated values based on survey Measurements made several days after the BRAVO detonation (0C68). The external exposure at Rongelap and Utirik Atolls since rehabitation varied due to radioactive decay of BRAVO fallout and the addition of low-level contamination from several other nuclear tests (see Figs. 7 and 8). The estimated total fifty-year background subtracted exposure post rehabitation was 5.9x107* Cc wg (2.3 R) at Rongelap Island and 1.5x%1077 Cc ke (5.6 R) at Utirik Island. These values were based on the exposure-rate history for each island and do not include the exposure contribution prior to rehabitation or from natural background radiation. The background exposure rate was measured by Miltenberger and Greenhouse (Gr77b) and was 9.6x10 ! nc xg h . 18 (3.7x10 Rh The fifty-