The same tendency of regional diffe-
On the other hand, the
In the North Equatorial
The predominance of 95Zr-95Nb in plankton was re-
Resear-
concentrations of 1 ‘cs,
content of fishes. On the other hand, no appreciate amount
of 2°Zr - 95Nb was found in other organs of fishes.
Ok in the plankton and the gill, intestine and stomach
gpalysis, 95Zr ~ 99Nb, was easily detected with 652n and
TSsues| were 1.07<9.54 uuc/Kg (0.05~0.43 s.u.) in
6~18.54 “esfKg (0.29~0.58 seu.) in the
n skin. In the intestinal organs, 146 ~357auo/Kg
365
of °-2n and 60 ~147 uuofKg of 60co, were determined.
According to the results obtained by gamma-ray pyls hight
Concentrations of 90gy
#a¢/Kg, and that of sr, were from
0.1 to 0.2 aacfKg of wet samnle.
varied from 6.0 to 22.5
Tsh muscles}
Radiological Seiences and Japan Analytical Chemistry
ray Scintilation surveymeter, and detectable radioactivity
were not observed, Radiochemical analysis on sample fishes
were carried out in two institutes as National Institute of
The radioactivity survey on fish surface was done with 7 -
cognized with r-ray spectrometer by Tokai Regional Fisheries
Research Laboratry.
served,
among the types of organisms and currents was hardly ob-
This was approximately equal to the data obtained in
Japanese waters. Differences in radiation contamination
1172 dpm/O.5g of ash.
Gross f-radioactivity inplanktoy ranged from 114 to
at
aters/under survey were practically all of a low level.
In general, it was recognized that the activity in the
Current, higher concentrations of nuclides were found above
the thermocline than below.
for 137¢s and 1.5 ##¢/é for l44ce.
mean values found in the North Equatorial Current and
Equatorial Countercurrent were 0.2 nac/g for 99Sr, 0.4 nuc/g
for’ 137s and 0.5 ##0/g of 144ce.
in the Equatorial Current were 0.1 uuc/g for sr, O31 aady
rence in the concentration of nuclides was also observed.
According to the results obtained by Hydrographic Division,
Maritime Sofety Board Agency, the mean
registered 1-3 “4°/,,
The comparative results of o11 types of physica
and
did not reveal any significant symptoms which could be regarded
as products of radiation.
“biochemical examinations of the crew before and after the cruis
S0-m}
dual
Based on measurements made with film badges, indivi
an
tessth
was
cruise
entire
the
radiation exposure doses during
Helth Pbysic