te ae
NR lemecrehtn t
e
bao
e te
fies
fs
14
Table 7
Mortality. 1954-1966. by Age as of 1954
Group
Age:
Rongelap {175 rads)
Ailingnae (69 rads)
Unexposed**
<10
11-20
21-30
31-40
41-30
51-60
61-70
71-80
> 80
0/19*
0/6
0/56
1/13
0/1
0/28
0/10
0/1
0/30
0/5
1/5
2/18
2/7
0/1
3/21
2/5
O/1
3/17
/i
3/3
2/7
2/3
0/1
1/1
Lyi
*Mortality/numberin group.
**Phis group was not examined until 1957.
neck and face complicating diabetes, and a 68-
Births
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
Twelve babies were born to exposed parents and
13 to unexposed parents during the period be-.
tween March 1964 and March 1966. The birth
rate per year is calculated from the number of
births per women of childbearing age (15 to 45).
There were 30 such women in the exposed group
(including 3 unexposed women whose spouses are
year-old woman (No. 894) died of pneumonia
deaths per 1000 per annum (11.7 for the more
‘heavily exposed group and 18.3 for the smaller
Ailingnae group) compared with 8.3 per 1000 for
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 accordingto
decade of death. A x’? test for significance,* comparing groupsof exposed and unexposedpeople,
showed thatthe mortality in the Ailingnae group
alone wassignificantly greater than in the control
group. The Rongelap exposed group combined
with the Ailingnae exposed also showed significant difference compared with the unexposed.
These results should be interpreted with caution
since the numbers ofpeople involved are too small
for a sensitive statistical test. None of the deaths in
the exposed group can berelated directly to radia-
tion exposure. The causes of death are similar to
those in the unexposed population. The slightly
greater mortality in the exposed Rongelap people
may berelated in part, at least, to the larger per-
centage 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 relationship with radiation
exposure.
*We are grateful to Mr. Keith Thompson of Brookhaven
auonal Laboratoryfor carrving out the statistical analvses.
3008298
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 unexposed parents.
Congenital Anomalies.
Two abnormal babies
were noted during the 1965 survey. One was a hy-
drocephalic (No. 1061) and the other a mongoloid
(No. 1055).
Sex Ratio.
Table 9 lists the births by sex in re-
lation to the exposureof the parents. There appears
to be no radiation-induced sex ratio alteration.
Miscarriages and Stillbirths.
A total of 5 mis-
carriages occurred overthe past 2-year period, all in
unexposed women, one of whom (No. 959) had 3.
As had been noted earlier, the exposed women
had a somewhatgreaterincidence of miscarriges
andstillbirths over the first 4 years post exposure
(see Table 8). During 1954-58 the exposed women
had 13 miscarriages of 32 total pregnancies (40.6%
incidence), and the unexposed women had 8 miscarriages in 49 pregnancies (16.3% incidence) during the 4-year period 1956-60. A x* test for significance* showed that total miscarriages and stillbirths weresignificantly greater (at the 5% level)
in the exposed women compared with unexposed
‘during the first 4 years, but there was no signifi-
cant difference after this period. Since 1958 the
exposed women have had 5 miscarriages in +8
pregnancies (10.4%) and the unexposed women
10 miscarriages in 62 pregnancies (16.1%).