INTERNAL DEPOSITION OF RADIONUCLIDES 73 Table 5.5.—Radiochemical Analysis of Urine From the Rongelap People (45 days post detonation) Beta ACTIVITY—D/mM/24 Hour SAMILE NO. G Nowmes | sm) 12-2 ---__-_- ween ee eee eee eee 2..----- one eee ee eee $__-----_- wee wee eee eee 4.0.2 22- wee ee eee wees a 1370 1260 1020 1210 §-_---- eee eee pene ee 1460 1200 727 Average_.-._...-------------------Percent of total Beta activity. ___..._- 1253 100 6. ----- anole wee eee eee eee eee on the radioactive content of yarious tissues. Details of the animal study are presented in a subsequent section. The estimate of the mean body burdenof the Rongelap group at 82 days post detonation is presented in Table 5.6. The body burden at one day was calculated in the following manner. A formula was obtained fromurinaryexcretion data reported by Cowan, Farabee and Love (6) in a case of accidental inhalation of Sr”. The excretion curve was best represented by four exponential terms. (Very similar results were obtained by approximating the biological decay of strontium with a power function, based on human excretion of the metabolically similar element, radium) (6, 7,8). Estimates were made of other radioelements ae) | R BASa F 490 510 480 626 120 130 120 150 197 244 324 284 328 110 170 353 526 42 134 10.7 312 20. 5 474 present in significant amounts at one day, as shown in Table 5.6. These estimates were made on the basis of the level of Sr* at one day, towether with the data on the activity of the various fission products at this same time (9) and animal isotope absorption and retention data (1, 5). The LAST has also estimated the body burden at one day, on the basis of radiochemical analysis of pooled urine saniples from a representative number of the Rongelap and American groups (10). These calculations were based on the analysis of 1" in the early samples of urine (15 days post detonation) as well as the above mentioned physical and biological data onfission products (1, 5,9). Their findings are presented in Table 5.6. Table 5.6—Mean Body Burden of the Rongelap Group ACTIVITY AT 82 Days uC (USNRDL) RADIOISOTOPE eS eee eee 0. 19 0. O21 0. 03 Bato Rare earth group. _.-_-- =. 0 T8! (in thyroid). ee a Rus oo ee Cate _ owe eee ee ee ee eee a Fissile material. ___..._-__-______ ~ oe ee | | — Cs4 md C3 cm Cs 881712 O-—d6 G — 0 0 ! ACTIVITY AT 1 Day uC (USNRDL) 1.6 2.7 1.2 6.4 — 0 0 ACTIVITY AT 1 Day uC (LASL) 2. 2 0. 34 — 11.2 0. 013 0. 019 0. 016 (ugm)