12
Ocean in 1954. Fourteen of them were examined
under hospitalization, and the other four were
treated as outpatients. At first we planned to
examine ail the exposed persons (twenty-two in
total), however, mainly for reasons of their own,
we could not include four of them in the 1964
survey.
In general, these persons had been in good
health during the past years. Although several
diseases occurred in some of them, there was no
definite reason to relate the radiation exposure
to such diseases. Since most of them got children after being discharged from hospitals, it
would seem evident that permanentsterility did
not occur in them.
The routine physical examinations of 1964
revealed that liver was palpable in ten cases.
However, it was not cirrhotic, and did not seem
to be related to liver disturbances. The routine
physical examination had no observation to be
relatable to the radiation exposure.
Residual beta burns of the skin were noted in
13 people of the 18 examined. The burns were
observed in wrists, external ears, abdominalwalls,
foot and leg. Most remarkable ones were those
seen in abdominal walls. Skin biopsies of the
abdominal walls were performed in six cases.
Histological diagnosis as well as macroscopic
examination of these lesions indicated no malignant change. In two cases that showed complete
epilation at the time of the accident, a small
alopecic area wasstill noted in each scalp.
Ophthalmological studies revealed lens opacities in 7 cases, in which 2 cases showed op~ ‘° of posterior capsules. However, these changes
had not characteristic features described about
progressed cataracts of atomic bomb survivors
in Hiroshima, although lens opacities of 2 cases
were found in posterior. Further ophthalmological survey should be needed.
Haematological survey showed that the results
of peripheral blood examinations were almost
normal, although neutropenia, lymphopenia, eosinophilia and slight basophilias were observed in
one or two cases respectively. N. AP-ase-score
decreased in one case. Bone marrow examinations revealed slight increase of myeloblasts
and M/E ratio in Cases T-3 ond K-12 respectively. “ Mitotically Connected Abnormalities”
were found in a few cases. In view of these
findings, it could be indicated that there is some
residual effect of radiation exposure on haematopoiesis on these persons.
Chromosomeobservations of peripheral leucocytes were made in 13 cases. The average rate
of chromosomeaberrations was much higher than
that in the normal. The frequency of aneuploid
cells was higher, aud chromosome-type abnormalities such as dicentric chromosomes and monocentric abnormal chromosomeswere frequently
observed. Cells with dicentric chromosomes occurred in 7 cases, and those with monocentric
abnormal chromosomes were present in all of the
cases. To trace the fate of such cells with chro-
mosome abnormalities persisting in them seems
to be necessaryin the succeeding annual inves-
tigations.
There were some abnormal findings in different
laboratory studies. However, it was not proved
that radiation exposure was related to these results.
Whole body counting and determination of
urinary excretion of '’Cs and "Sr were carried
out. No significant increase of '’Cs or “Sr was
found on the exposed persons by the examinations.
|
In general, the results of 1964 medical survey
on Japanese fishermen did not indicate clinically
significant late effects of the fall-out exposure in
1954. However, it seems to be very important
as well as necessary to conduct further medical
survey to detect the significance of subtle changes
such as observed in haematological, chromosomal
or ophthalmological examinations.