bimodal activity ingestion rate distribution for 905, in the Rongelap population, Data for 9c and 6525 were noc sufficient for analysis for the Utirik Atoll residents. Values for Ke observed st Rongelap were assigned’ to Utirik males and females and body burden histories for population subgroups were reconstructedusing Eq. 1 or'2. Figures 7 and 8 illustrate| the derived mean adult body burdens for all significant nuclides studied on fongelep and Utirik. This method provides abast’ fit of the data shown in Figures 2 through 6, and provides a body burden history during the early years post return at Utirik, a « toby time when body burden measurements were not made. Actual data points are also plotted to demonstrate the fit, The curves shown for ae in Figures 7 and 8 were obtained by setting Ke equal to zero. future ones. This underestimated the initial body burdens and overestimated Since 35 p¢ contributed less than 1,0% to the total dose equiva~ lent, an arbitrary assignment of Kp based on observed values for the other inclides was not attempted. During 1974, another series of blood samples was obtained from Rongelap and Utirik (Co75). reported. Analysis for 73 re hae yet to be A recalculation of 5556 body burden and its impact on early dose equivalent rates will be conducted when the data is made available. A substan- tial change in dose equivalent is not to be expected. Figure 4 and Figure 6 illustrate the observed adult histories of 905, and 137 06 mean urine activity concentrations. adults were plotted. Figure 7. Mean values for adult males or al! a "a oe Measured values for 1376, body burdens were also shown in A much smoother curve was plotted in Figure 7 and it was determinc: that the collection and analysis technique for urine samples introduced the idditional variations. . . : 137 Cs, a smooth brady On the basis of this observation for 17 12 be regs “rei ” mA: TPTET IE: “O aa