39 relative immunoseems to indicate a reduction in antibody relogical capacity or at least lowered ency for the serves in the exposed people. The tend tively greater depression of these moieties to be rela to be al re. . it the age. anti1 age mma ies to d the Perconrease sable ve. If ‘grity culo- light y, no arate rious efore 3SO0CIthese n the It bendered to + satsAAin Rl ng in ther gree ied aging effect. Since such studies were not carr e out earlier, it is not possible to say when thes expost s year 3 at r, changes developed. Howeve posure, when the people were challenged with s tetanus toxoid, primary and secondary response t the in eren y diff antl ific sign were found notto be exposed and unexposed populations.® Also, in spite ofslight depression of blood elements andreduced serum globulin levels, the exposed Marshallese people, on the basis of our observations over a 15-year period since the accident, have shown no recognizable impairment of immunological capac- ity as evidenced by the incidenceof, or susceptibility to,illness or diseases.58 If theserum protein changesare a recent development, then such impairment may yet become apparentif the people are faced with a virulent antigenic challenge in the future. Thelack of any differences between the exposed and unexposed people in transformation of lymphocytes in response to PHAstimulation is somewhat unexpected in view of the abovefindings. However, the lymphocyte levels in the exposed group have not been depressed as severely as some ed to . duced n-in in the older groups may implya radiatio on of cually on of ~»yosed festa- order to obtain base-line data, 24-hr urine samples were collected from 14 of the people at Kili in 1969 and brought back for radiochemicalanalyses. ESTIMATION OF INTERNAL BODY BURDENS OF RADIONUCLIDES IN MARSHALLESE ses on the Rongelap and Bikini people for calcium, 90Sr, and 137Cs for 1967, 1968, and 1969are listed in The last evaluation of body burdens of gamma emitting isotopes in the Marshallese was done in *Radiochemical analyses were done at the Environment Studies Division, Health and Safety Laboratory, AEC, New there may be nosignificant depression of lymphocytes capable of responding to PHAstimulation. Individualresults of radiochemical urine analy- 1965 on 179 Rongelap people"! in a shadow-shield York, by Mr. Edward P. Hardy. Table 17 such been ‘ssion Summary of Marshall Island Radiochemical Urine Analyses, 1967-1969 1967 il ex- 1e semens ding. - Island, several hundred miles to the south. In of the other blood elements, which indcates that opol- nulins lesser lains whole-body counter with an 11%-in. Nal(TH) crystal. Radioisotope levels in the exposed and unexposed people were indistinguishable by this method, both groups showing elevated total body burdens of 10 to 20 nCi 137Cs and 1/1000 this amountof 6°Co. Also in 1965 radiochemical urine analyses were done on 24-hr samples from 23 people and on two pooled samples. The results showed no increase in internal body burdens since 1961; therefore, no whole-body counts were considered necessary duringthe next 3 years (19661969). However, urine samples were collected for radiochemical analyses* as follows: 24 in 1967, 22 in 1968, and 23 in 1969. The urines were analyzed first for 157Cs by gammaspectroscopy by counting the wet ashed samples on top of an 8 x 4-in. NalI(T)) crystal. Then the residues were dissolved and analyzed radiochemically for 137Cs and ®°Sr, Calcium was determined by the oxalate-permanganatetitration method. Because oftheir high 9°Sr and 137Cs content, coconut crabs on Rongelap Atoll have been banned for use as food. Several crabs were brought back for radiochemicalanalysis during the past 3 years. Our group at BNL has been given the responsibility for monitoring the radioactive body burdens of the Bikini people when theyreturn to live on their homeisland.59 They are nowliving on Kili Rongelap exposed Rongelap unexposed Kili 500b29b 1968 1969 90Sr, 137Cs, 90Sr, 137Cs, 9Sr, 137Cs, pCi/liter nCi/liter pCi/liter nCi/liter pCi/liter nCi/liter 2.5 3.0 4.8 4.8 27 5.6 2.8 2.8 4.9 4.1 0.48 3.4 2.9 0.34 7. OES weese With nlza. a the