Io wn ee Table 33 Urinary Sr Levels. in uuC/1, of Marshallese, 1959 Males Age 1-15 * Rongelap exposed Rongefap unexposed Aulingnae Utirik Ebeye 2.4 Females Age > 15 (2)* 7.12=2.0 (3) Age 1-15 7.3 5.1 3.9 (2) 3.3 15 +09 0.56 0.37 (4) 3.9 (1) - 5.6 =2.3 - ~ Age >15 5.4 £2.2 (9) 4.2 42.3 (6) 3.0 (1) 2.5 (2) 0.700.70 (3) *The numbers in parentheses are the numbers of people in the groups. Table 34 Cs'*" Body Burdens, in muC/kg, of Marshallese as Measured by Whole-Body Gamma Spectroscopy, 1959 14.2+5.1 (10) 14.0%4.7 (37) 11.536 (4) 4.51.6 (15) 11.32.7 (12) 9.92.1 (15) 10.043.1 (4) 4.51.9 (14) 11.0%3.4 (16) 9.82.8 £33) li.44%45 (5) 3.61.3 £15) *Toc :umbers in parentheses are the numbers ofpeople in the groups. on an average 24-hr urine output of 1660 ml (see Table 33). No significant difference was found between the Rongelap exposed and unexposed groups, although the exposed adult group hada slightly higher mean value than the unexposed group. Females tended to have a lower mean Sr®® value than males, but the difference was notsta- ment with the value of 140 days obtained by An- derson,°*? but a biological half-time of 51 to 59 days was obtained in clinical study made over a 4-month period following injection of Cs**’Cl, into two patients.** The estimates of body burden of Cs!” in 1958, tistically significant. Relatively few children <15 derived indirectly from urinalysis, are presented in Table 32. it was not possible to compare their levels statis- 1957 indicates that the Rongelap people were ex- years of age weretested for urinary Sr®°; therefore, The urinary excretion of Cs'*’ of 34 wuC/] in tically with those of the adults. The mean Sr** urinary value for an adult inhabitant of Utirik was 1.8 puC/1, which is about 35% that of the Ronge- posed to a continuing low level of Cs'*? from stratospheric fallout during 1956 while residing on Majuro. By contrast, the mean body burden of contaminated) had stil] lower values, 0.62 puC/t. exposed and unexposed groups on Rongelap seems, turned to their atoll in 1954) was 334 muC, considerably higher than that of the Rongelap people who were residing on Majuro at that time.*° This the initial exposure is detectable in the exposeda can be attributed to the higherlevel of Cs**" con- lap group. The control group on EbeyeIsland (not The lack of significant difference between the to indicate that essentially no residual Sr®° from group, Cesium-137. The Cs'** urinary excretion levels _ of the Marshallese people for the period from 50 to 180 days following exposure can be expressed as a single exponential function with a half-life of 70 days (see Figure 56). This figure is not in agree- Cs'*? in 1957 of the Utirik people (who werere- higher burden among the Utirik people in 1957 tamination on Utirik than on Majuroat that time. Zinc-65. Zn* urinary levels were not measured before 1958. With the assumptionsthat excretion of Zn** is exponential and urinary excretion is 10% of total excretion (urinary/fecal ratio=), the March 19538 urinary excretion level of 175 a Age >15_ ee 12.4+6.2 (9)* 11.8+4.8 (20) 8.9 (2) 4.61.2 (14) Age 1-15 Me Rongelap exposed Rongelap unexposed Ailingnae Utiri: Age >15 4 Age 1-15 ty ind a, Males