33 tion and various comparison populationssince in the exposed population will be compared with those in the unexposedfor differences that might indicate possible premature aging effects. As pointed out, such differences have not been apparentthusfar. exposure in March 1954. In Appendices 3 and 4 are listed the individual! blood counts for 1959 and 1960. The data are also summarized graphically in Figures 33, 35, and 38. The blood data have been classified as in the past according to age and sex. The results of blood counts in the 1959 and 1960 surveys may be summarizedas follows. White Blood Counts. The mean WBCin 1959 RESIDUAL BETA BURNS Ten people continued to show residual skin damagefrom beta burns sustained 6 years pre- showed a further trend upwardin both the ex- viously. Most ofthe residua consisted of very mild posed and unexposed populations, beingslightly lower in the former(see Table 21 and Figure 33). The 1960 WBC level of the exposed people showeda considerable drop from a meanlevel of 9500 in 1959 to 6500 in 1960 as compared with the trend duringthe previous two years (no counts changes, such as varying degrees of pigmentalteration giving a mottled appearance, sometimes ac- companied by a rougheningofthe skin (increased rugosity). Some showed more pronouncedchanges, such as atrophy and scarring. None of the more severe residual lesions showed any gross evidence of breakdown with the development of chronic radiation dermatitis or any premalignant or malignant change. No biopsies were taken. Several women whohadsustained moresevere neck lesions seemed to be showing an increase in pigmented moles in and around the affected areas. However, were made on unexposed people in 1960). The ex- planation for this is not clear. The percentage distribution of the various white cell levels was not very different, however, from that of the previous values. Neutrophils. The neutrophils in 1959 (Table 21 and Figure 33) showed an increase corresponding to the increase in WBC in both exposed and unexposed populations, the meanlevel also being this is not certain, and these moles will be ob- served carefully in the future for anv suspicious changes. In Tabie 20 are listed descriptions of the slightly lower in the exposed. A scattergram residual beta burns seen in 1960. Figure 32 shows healed beta burnsof the feet 5 years after exposure. (Figure 34) of the age distribution of the counts in 1959 showsa greater tendencyfor the vounger groups to have lower mean countsin the exposed than in the unexposed populations. This was noted also in 1958. In 1960 the average of neutrophil counts was 3500 for the exposed group compared with 4800 in 1959. This decrease corresponded with the decrease in the total white count. LABORATORY EXAMINATIONS Hematological In. Appendices 1 and 2 are presented summaries of the mean blood counts of the exposed popula- Table 21 Mean Leukocyte and Platelet Counts, 1959 and 1960, by Age and Sex Rongelap exposed 1959 WBC (x10), age Neut. (107°), age Lymph.(x 10-3), age Mono. (10°*),. age Eosin. (X10°7), age _ Baso.(x10°*), age >5 >5 >5 >5 >5 >5 95+ 48+ 4.0% 20> 5.0+ 0.4% 2.3% 1.9 1.3 18 3.3 0.6 1960 (60)** 6541.8 (60) 3.51.5 (60) 2.7408 (60) 0620.2 (60) 2.70.8 (60) 0420.11 Plate. (10-*), Malesage5-10 32.3410.0 ( 7) Females *Scandard deviation. Ailingnae exposed >10 244> 9.9 (20) >5 27.6210.5 (29) - - (54) (54) (54). (54) (54) (54) 1959 1960 9.742.4(15) 5.122.115) 3.741.1(15) 3.2%2.5(15) 6.044.2(15) 0.50.8 (15) 7.34.3 (14) 3.62%1.6 (13) 3.01.2 (13) 0.6+0.6 (13) 4.040.2 (13) 0420.4 (13) 26.3+6.0( 4) 26.823.7 ( 9) - 40.9 **The numbers in parentheses are the numbers of people in the groups. ( 2) - Unexposed 1959 10.1 3.24% 4.14% 2.4 6.0 0.5 3.1 (123) 2.1 (123) 1.4(123) 2.3 (123) 9.9 (123) 0.8 (123) 34.6-10.8( 11) 28.0 8.4( 54) 31.14% 7.2( 52)