14 Table 7 Mortality, 1954-1966, by Age as of 1954 Group Age << 10 Rongelap '175 rads) 0.19" Unexposed ** 0/56 Auingnae (69 rads} 0:6 11-20 1-13 O;} 0/28 21-30 31-40 0/10 0.5 0/30 2/18 0-1 *Mortality/numberin group. neck and face complicating diabetes, and a 68year-old woman (No. 894) died of pneumunia complicating Asiatic influenza. A 91-year-old male (No. 862) died presumably of cardiovascular disease; he had been quite senile and bedridden for the past few years. During the past 12 years, 13 deaths have occurred in the exposed group. This represents 13.0 deaths per 1900 per annum (11.7 for the more heavily exposed group and 18.3 for the smaller Ailingnae group)-compared with 8.3 per 1000for the Marshall Islands as a whole in 1960. In Table 7 mortalities for the exposed Rongelap and Ailingnae groups as well as the unexposed comparison population are presented according to decade of death.A x test for significance,* comparing groups of exposed and unexposed people, showed that the mortality in the Ailingnae group alone wassignificantly greater than in the control group. The Rongelap exposed group combined with the Ailingnae exposed also showed a significant difference compared with the unexposed. These results should be interpreted with caution since the numbers of people involved are too small for a sensitive statistical test. None of the deaths in the exposed group can be related directly to radiation exposure. The causes of death are similar to those in the unexposed population. The slightly greater mortality in the exposed Rongelap people mayberelated in part, at least, to the larger percentage of older people originally in this group. No cases. of leukemia have appeared in the exposed population. Twoearlier deaths from cancer in exposed women and the recent development of a malignant thyroid nodule, to be described below, make it necessary to. keep in mind the possibility of causal relauionship with radiation CX POsure "We oate vrateful to Mer Kerth Thompson of Brookhaver National Laboratory dor carmang gut (he statistical analyses 41-50 51-60 2.7 1,5 0/1 3/21 2°5 0/1 3/17 61-70 74-80. > 80 a 2/3 1 | 2:7 0.1 14 3/3 - - **This group was not examined unul 1957. Births Twelve babies were born to exposed parents and 13 to unexposed pavents during the period between March 1964 and March 1966. The birth rate per year is calculated from the number of births per womenof childbearing age (15 to 45). There were 30 such women in the exposed group (including 3 unexposed women whose spouses are exposed males) and 32 in the unexposed group (see Table 8). From these data, there appears to be no difference in fertility between. the two groups. All these babies appeared normal except for the two listed below, who were both offspring of un- exposed parents. Congenital Anomalies. Two abnormal babies were noted during ihe 1965 survey. One was a hydrocephalic (No. 1061) and the other a mongoloid (No. 1055). Sex Ratio. Table 9 lists the births by sex in relation to the exposureof the parents. There appears to be no radiation-induced sex ratio alteration. Miscarriages and Stillbirths. A total of 5 miscarriages occurred overthe past 2-year period, al] in unexposed women, one of whom (No. 959) had 3. As had been noted earlier, the exposed women had a somewhat greater incidence of miscarriges and sullbirths over the first 4 years post exposure (see Table 8). During 1954-58 the exposed women had 12 miscarriages of 32 total pregnancies (40.6% incidence), and the unexposed women had 8 mis- carriages in 49 pregnancies (16.3% incidence) during the 4-year period 1956-60. A x’test for significance* showed that total miscarriages and suillbirths were significantly greater (at the 5% level) in the exposed women compared with unexposed during the first + years, but there was nosignifi- cant difference after this period. Since 1958 the exposed women have had 3 miscarriages in 45 pregnancies (10.4'.) and the unexposed women 10 miscarriages in 62 pregnancies (16.1).