30 Table 13 Peripheral Bloou Cultures Diploid numbers Total Subject No. counts 10 11 14 27 41 50 58 69 79 80 10 59 24 26 30 27 69 32 19 19 16 22 32 36 37 1 1 1 1 1 1 39 40 2 2 I 41 42 43 44 45 46 47 48 2 7? #3 2 I 1 4 %33(56%) 20 (80%) 22 (84%) 18(60%) 25 (92% ) §51(74%) 29(91%) 18 (95%) 15 (79%) 8 (50%) § i 1 5 1 1 1 6 2 2 4 I 1 i reached the highest levels yet recorded. The general anemic tendencyin the people is no longer as pronounced. Perhaps a better diet (increased amounts of fruits and vegetables} may partly ac- count for this change. Comparison of hematological data in the ex- posed and unexposed groups demonstrates a defi- cit in total leukocytes and absolute neutrophils and lymphocytes which is even slightly more pro- nounced this year than last year, Platelet levels in the exposed group showslightly less deficit this year than in the past. As noted previously, this deficit in leukocytes and platelets is more apparent in the younger and older groups. Erythrocyte counts and hematocrit and hemoglobin levels were again found to be about the same in the exposed as in the unexposed group. In view of these findings in the peripheral blood and the evidence of slight persisting bone marrow abnormalities, it does not seem unreasonable to assume that there is some residual effect of the radiation exposure on hematopoiesis. The finding of slightly lower leukocyte levels in the male ard female children of exposed parents Is difficult to evaluate. OTHER LABORATORY STUDIES Chromosome Studies Although moderate to good growth of peripheral blood cultures was obtained in samples from | 4 1 1 1 67 pp 1 1 1 13 of 20 unexposed and 30 of 51 exposed people, the final chromosome smears unfortunately yielded countable metaphases in only 10 preparations in the exposed group. The difficulty in obtaining good smears is believed to have been related to the high temperature and humidity of the Islands, which interfered with rapid drying of the smears. This was particularly disappointing since excellent smears had been obtained in preliminary perfec- tion of the technique under laboratory conditions at BNL. Similar difficulties with chromosome spreads and poor staining were encountered in 9 direct bone marrow metaphase studies. Neverthe- less, small numbers of dicentrics were noted in some of these preparations along with abnormal diploid numbers (sce Tables 13 and 14). These preliminary findings suggest that persistent damage to blood cells occurred in these people. In view of the importance of these studies, a concerted effort will be made on the next survey to obtain a large number of satisfactory preparations from peripheral blood and also from cultures of the skin in areas previously involved with beta burns. It is believed that the difficultics encountered in the field in making the chromosome smears can be corrected by using a hot air dryer on the next survey. Routine Urine Analyses Routine urine analyses were carried out on the majority of the people. Ten of the samples were positive for sugar. Sever) of these shoved only