.23 Laboratory Examinations older (age >40) groups than in the middle (age 15 to 40) group. This is demonstrated in the histogram (Figure 30) and in the scattergrams (Fig- HEMATOLOGICAL ures 19 and 20), the latter showing more than half the individual counts below the meanline of the Summarytables of hematological data are pre- unexposed. An accumulative percentage distribution curve (Figure 21) also showsthe lower counts dices. The more heavily exposed Rongelap group who received 175 r are designated as “Rongelap posed group. These findings conform generally with previous data except that the younger females tend to show more depression. sented in the tables and graphs in the text, and raw data on the individuals are presented in the appen- exposed,” the Rongelap people who received a smaller exposure of 69 r as “‘Ailingnae exposed,” and the larger unexposed comparison population of Rongelap as “unexposed.” Because of the smail (displacement of the curve to the left) in the ex- Lymphocytes number of people in the Ailingnae group, their data were nottreated as fully as those for the larger groups, and are briefly summarized in a separate paragraph. Because ofcertain differences noted in age and sex groups between the exposed and the unexposed, in addition to the comparisons of meau levels for entire groups, comparisons are also made The mean absolute lymphocyte level in the exposed is 24% below that of the unexposed, which indicates a deficit greater than the mean neutrophil dciicit (see Table 10 and Figure 22). The lymphocyte levels appear to be more depressed this year. >40 yr for cach sex are compared, The hematological data are summarized in with neutrophils) a somewhat larger deficit appears among the younger females. The scattergrams (Figures 23 and 24) and the accumulative distribution curve (Figure 25) also confirm these observations. of age and sex groups. Ages 8 to 15, 16 to 40, and Tables 10 and 11 and in Figures 18 through 37, In Appendices 1 and 2 are presented summaries of the mean blood counts of the exposed population and of the various comparison populatious since exposure in March 1954, In Appendix 3 arelisted the individual blood counts for 1962. In Appendix 4, the individual alkaline phosphatase and basophil counts are presented. Leukocytes The leukocyte levels in both exposed and unexposed groups were slightly lower than last year (sce Table 10 and Figure 18). The mean leukocyte level in the exposed group was slightly (12% ) below that in the unexposed group. This waslargely a reflection of deficits in the neutrophil and lymphocyte levels. Neutrophils The mean neutrophil level in the Rongelap exposed group was 13.6% below that in the unexposed group (see Table 10 and Figure 18). The levels were lower in the younger (age 8 to 15) and The histogram (Figure 30) shows that the deficit in lymphocytes seemsto be distributed fairly evenly in the age and sex groups, except that (as noted Eosinophils, Monocytes, and Basophils These all showed nearly the same mean levels in both groups. The general persistence of eosinophilia in both groups was apparent, as in past surveys. Platelets Meanplatelet counts in both exposed and unexposed groups were higher this year than previously (Figure 26). The male counts this year averaged about the same as the female; previously the female counts had been higher. As noted consistently in the past, mean counts in both males and females in the exposed group were slightly below the corresponding unexposed levels (males by 5.7%, females by 10% ). Also as previously noted, the younger and older groups showed the grcater deficit (see histogram, Figure 30). Scattergrams (Figures 27 and 28) show that the majority of