32 Neutropuits. The neutrophil levels increased slightly at the time of the 9 and 10-year surveys in both exposed and comparison populations. At 9 years the neutrophil levels were about 5% lowerin the exposed than in the comparison group,butat 10 years they were about 20% lower. Neutrophil levels are shown in Figures 23 through 29. The neutrophil deficit was greater in the exposed group whoreceived 175 rads are designated as “Rongelap exposed,” the Rongelap people who received a smaller exposure of 69 radsas “‘Ailingnae exposed,” and the larger unexposed comparison population of Rongelap as “unexposed.” Because of the small numberof people in the Ailingnae group, their data were not treated as fully as those for the Rongelap groups, andarebriefly summa- rized in a separate paragraph. The Utirik data younger age groups (<40 years). The exposed older age groups ( >40 years) did not share the deficit as muchas has been notedin the past(Figures 26 through 29). Lympuocytes. Lymphocyte levels were slightly higher in the exposed and unexposed groups dur- are summarizedseparately also. Because of certain differences noted in age and sex groups between the exposed and the unexposed, in addition to the comparisons of mean levels for entire groups, comparisons are also madeof age and sex groups. Ages 9 to 15, 16 to 40, and >40 years for each sex are compared. ing the 9 and 10-year surveys. In contrast to the 8-year survey results, the lymphocyte meanlevels showedlittle difference between the exposed and unexposed groups during the 9 and 10-year surveys; however, some individual lymphocyte counts were lowerin the exposed group. Lymphocytelevels are shownin Figures 24, 25, and 30 through 34. 7 T t T oT 3S 3 oo oO T on oO T | | Bey oO 7 CUMULATIVE (%) | | (26-30 Days) (31-59 DAYS) = 1 (31-59 Days) E1359 qT oO 0 Mostof the difference was due to lower neutrophil levels in the exposed group (see Figure 23). LEUKOCYTES AND NEUTROPHILS x i073 T Sy Mean slightly lower leukocytes than the unexposed (—4%) at 9 years, and at 10 years, lower by 9%. T oO Leukocytes. levels of leukocytes in both exposed and comparison populationsat 9 years post exposure wereincreased over the 8-year levels, and the 10-year levels were higher than thosefor either of the two preceding years. The exposed group had only y * EXPOSED, 9 YEARS POST EXPOSURE 4 UNEXPOSED ® EXPOSED, TIME OF MAXIMUM DEPRESSION ny Rongelap Population. T I The hematological data are summarized in Tables 18 and 19 and in Figures 23 through 49. In Appendices1, 2, and 3 are presented summaries of the mean blood counts of the exposed populations and of the various comparison populations since exposure in March 1954. In Appendices 4 and 5 arelisted the individual blood counts for 1963 and 1964. In Appendix 6 basophil counts are presented. J ot 4 260 40 60 80 0 NEUTROPHILS x 10> 20 40 60 20 LYMPHOCYTES xi0"? 40 60 PLATELETSx10 Figure 24. Cumulative percent distribution curvesfor neutrophils, lymphocytes, and platelets, 1963. v T T T T 5 ul - OAYS! F Qo [L789 x \ a NEUTROPHILS tippy tbat a 24 40 DAYS S672 6 | MO ft tf 23 4 TIME AFTER EXPOSURE bt 5 6 YEARS tt FF 8 39 10 Figure 23. Mean neutrophil and white blood counts of exposed Rongelap people from time of exposure through 10 years post exposure. Stars represent mean values of comparison population. I0Ge0l3 —_ \ i 80 2 60 T T TT TT T TT TT * EXPOSED, TEN YEARS POST EXPOSURE 4 CONTROL 2 EXPOSED, TIME OF MAXIMUM DEPRESSION “ DaYs} (26-30 DAYS] (31-59 T \ I 0 3 = 40 3 o 1 20 | | a ] | L tL 20 40 he 69 A i 89 NEUTS x 1073 _—l 20 on 40 LYMPHS x 1073 | 0 1 1 20 1 —L 40 60 PLATELETS x107* Figure 25. Cumulative percent distribution curves for neutrophils, lymphocytes, and platelets, 1964.