mulative percentage of neutrophils, lymphocvtes, and platelets at various times. From these datait appears that hemopoietic recovery in the exposed groups was incomplete during the first 15 years after exposure. Since that timethe levels in the exposed group have been about the sameasin the unexposed group. On the basis of RBC, hematocrit, and hemoglobin determinations, erythropoi- T T T 7 Siri BV =091 +0.090 (TBW) RCV =0.08 +-0.0474 (TBW) BV =0.647+0.115 (TBW) BV 3=0.5337 +0.0767(TBW) Moore | RCV=0 158 +0.05296 (TBW) Marshallese { RCV = ~0.1749 +.0.0441(TBW) Caucasians in Pacific Volume, liters this contention. T Regression lines etic function has been about the same in the ex- posed and in the comparison population. Thelag in recovery of leukocytes and platelets may represent residual bone marrow injury. The results of bone marrow and chromosomestudies and the development of a case of leukemia tend to support T { BV =1 2101 +0.0792 (TBW) RCV =0.19947 +0.0419 (TBW), Bk 4 53k 4 th 4 3 [ 4 be — 3. Bone Marrow Although bone marrow examinations at 6 monthspost exposure showed no gross abnormal- ities, smears on four exposed Rongelap people 10 years later showed alteration in the myeloiderythroid ratio in three of them, manifested by an increased numberofred cell precursors. In addition to hyperplasia. the findings included abnormalities of chromatin material with double nuclei and an increased numberof mitotic figures in the normoblastic series (see Figures 14 and 15).11 Occasionaily, bilobed lymphocytes have been noted in the peripheral blood of some exposed people. 4. Other Hematological Findings Total blood volumeand red cell volume were studied 10 vears after exposure.!!* No differences were found between exposed and unexposed Rongelap groups, but it was noted that blood volume andred cell volume tended to be reduced in many Marshailese compared with Americans?9(see Figure 16).12 Several other hematological observations,not related to radiation exposure, were noted. Eosinophilia >5% in more than half the people has been a consistent finding. This could be accounted for only-partly on the basis ofintestinal parasitism and maybe related also to numerous fungus infections of the skin and other chronic infections. Other findings possibly related to chronic infections are above-normal sedimentation rates and high gammaglobulin levels (both tending to increase with age). Varying degrees of anemia have been seen occasionally, particularly in wo- “These studies were done by Dr. L.M. Mever, Veterans Adminstration Hospital, Brooklyn, N.Y., and Dr. W.E. Sin, University of California at Berkeley. 2 Le W. Siri *. RED CELL VOLUME of seseeee Marshallese . ita z*” 0 4 10 F, Moore L = —-— Caucasians L i in Pacific 20 30 40 Total body water, liters ri 50 60 Figure 16. menof childbearing age. Price Jones sizing of red cells in these cases showeda slight microcytic tendency.§ Iron deficiency apparently was not the cause since serum iron usually was in the normal range.§ Reticulocyte counts have not been significantly increased in either the exposed or unexposed population. Macrocytic anemia has not been seen. Vitamin By levels have been unusually high in the Marshallese§; the cause of this is unknown but does not appearto berelated to liver disease or leukemia. Thesickling trait has not been seen in the Marshallese examined. D. SUBSEQUENT COURSE OF SKIN LESIONS The residual skin lesions noted in the Rongelap and Ailingnae people since the initial lesions are listed in Table 13. During thefirst year manyof the healed areas, particularly on the back of the neck, showed a roughening (rugosity) and bluishblack pigmentation, which becameless noticeable with time (see Figures 17 and 18). Deeper lesions exhibited early residual scarring andlackofpig-