458
FALLOUT EFFECTS—CONARD & HICKING
Internal absorption of radionuclides, largely
from eating and drinking contaminated food and
water, and to a lesser extent from inhalation of
fallout,
resulted in
detectable radioactivity in
urine samples. However, during the first few days
when the body burdens were highest the maximum
permissible concentrations were exceeded only
for **Sr and the radioisotopes of iodine. The dose
to the thyroid glands of the adults from the radio-
iodines absorbed was estimated to be about 150
to 160 rads.
Follow-Up
Health Status.—Medical evaluation of the health
status of the exposed people over the years since
the accident has revealed about the same incidence
of illness and disease as noted in the unexposed
population with certain exceptions noted below.
General health and nutrition have continued to be
satisfactory and comparable to the unexposed
comparison population. Annual hematologic follow-up studies revealed that the levels of white
2. Gross picture of sectional thyroid gland showing
nodules in 14-year-old Marshallese girl.
group, it was not statistically significant. The e
posed girls showed nosignificant differences cor:
pared with unexposed girls. The slight retardatic
of growth noted in the bows suggests that radiatic
may be a causal factor, although possible mech:
nisms are not clear. The dose to the bones from »:
ternally absorbed isotopes is believed to have bee
too small to have affected bone growth. These fin:
ings are being published in detail by Sutow et al
Development of Thyroid Nodules.—Thyroid noc
ules were detected in three girls nine and te
blood cells and platelets of the peripheral blood
in the exposed group never quite reached thelevels
of the unexposed comparison population (Fig 1).
years after exposure; two girls were 13 and on
was 14 years of age at the time of detection. The:
girls were in the higher dose group in which thei
were 29 children (<18 years of age); 17 of the 2
were girls, with 6 girls in the 10 to 15 year range
for the other Marshallese people. A recent study
in which certain criteria of aging were put on a
and 21 of the girls were in the age range of 10 i
Mortality and Aging.—There were ten deaths in
the exposed population over the ten-year period:
this represents a mortality rate near that observed
numerical basis did not reveal any differences in
age scores between the exposed and unexposed
groups.”
Fertility, Miscarriages. Stillbirths, and Genetic
Effects.—Effects on fertility were not apparent
as judged by comparison of the birth rates for the
exposed and unexposed populations. Possibly related to radiation exposure was the fact that dur-
Of 75 unexposed comparison children, 37 were gir.
15 years. No thyroid nodules were noted in thi
latter group. No lymph node involvement wa
grossly evident. The individuals were hospitalize
and two had complete thyroidectomies and th
third a partial thyroidectomy. Grossly. the gland
had a cobblestone appearance with multiple har
nodules and wereat first thought to be malignant
ing the first four years after exposure an increase
Sections of the tissues were reviewed by a numbe
of pathologists, all of whom agreed that the nod
ules were not malignant and resembled in man:
exposed women, 41%
ficiency, with its characteristic regenerative rathe
in miscarriages and stillbirths was noted in the
of the births
(13 in 32
respects adenomatoid goiter seen with iodine de
spring compared with 21% (8 in 38 births) in the
than neoplastic proliferation. It should be note
that goiters are rare in the Marshall islands sinc
no iodine deficiency exists (Fig 2 and 3).
of abnormalities in children of exposed compared
3. Section of thyroid gland shows characteristic multiple, discrete noduies with wide variation in size and
births) in this group terminated in nonviable off-
unexposed women. Nospecific genetic studies have
been carried out, but no difference in incidence
with those of unexposed women has been observed.
Growth and Development Studies.—Anthropometric examinations of the 42 exposed and 75 unexposed children have been conducted over the past
five years. Using nonparametric statistical meth-
ods, comparisons of weight, stature, and bone age
(the latter determined from roentgenograms oi
the wrist and knee) were made between exposed
and unexposed children of the same age groups.
foal
gta!
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Boys exposed at 1 to 5 years of age showed retardation of statural growth as well as bone age.
This was most marked in those boys exposed at
12 to 18 months of age. The average skeletal
maturation in the exposed boys was about seven
months behind their unexposed peers. Though
weight gain also appeared slightly retarded in this
growth pattern. Some consist of microfollicular tissue,
some of colloid cysts, while others show hyperplasia
with papillary infolding of epithelium.