EO ee ee er
INTERNAL
DEPOSITION
and the analysis at 4 months represents only
radiological decay. Thus, the results are not
directly comparable to those obtained from animals which were veturned alive, and jn which
biological turnover as well as rachological decay
were operating.
The largest fraction of the gross beta activity
in the fish was contributed by the concentration
of radioactive material in the viscera. In two
of the fish in which bones and muscle were sep-
arated and analysed, equal amounts of activity
were found in ench fraction.
WTowever, the
storage of these fish in formaldehyde for 3
months may have permitted the diffusion of
the radioelements fron: bone to muscle to take
place.
Further studies on fresh fish will clarify
OF
RADIONUCLIDES
may represent the distribution in luman beings.
The absolute amount of internal contamination
in the Roneelap people was, however, only 2
tenth of that found in the animals.
At 4 months post detonation, the alkaline
earths comprised less than 2 percent of the total
activity in the chum (Table 5.10).
beta activity. The balance of the activity was
contributed chiefly by Zr"* (21 percent) and
Rus (32 percent). About 40 percent of the
material found in the viscera of the fish wits
of the rare earth ereup. Very small amounts
of strontium and barium were found. In the
tissues of the fish, strontium, barium and the
rare earths contributed only abont 10 percent of
the total activity.
was considerably greater than that of the Jand
anunals studied. As fish form a Jaree staple
5.43
item in the diet of the Marshallese. the high
level of contamination 3s important.
At the end of a 214-month experimental
period, the excretion by the chickens of both
beta and gamma activity per 24 honrs was 5
percent of the value measured at the start at 87
days post detonation (Fig. 5.1).
Analysis of pig excreta indicated a
decrease of activity with time. In a
period, the gamma activity excreted
hours decrensed to about 2.4 percent of
similar
G-week
per 24
the ac-
tivity excreted at 44 days post detonntion.
The excreta of the pigs from Utirik contained
Jess than 10 percent of the gross bet activity
found in the excreta of the pigs from Rongelap
at the same time.
This ratio of 10 was approx-
imately the same ratio found between the activity of the food, water and soil samples of the
two locations.
Radiochemical Analysts of Tissues and Ex-
ereta,
Raciochemical analysis of pie tissues
licheated that 62 percent of the skeletal beta
activity was derived from Se". 7 percent from
Bat? and 10 percent from the rare earth sroup
at 8&2 days post detonation (Table 5). The
radioisotopic composition of the urine at this
time was similar to that of the skeleton. ‘The
distribution of activity an the body of the pig
9002159
The rare
earth group constituted 33 percent of the total
this point.
The contamination of the fish in the lagoon
$1
Autoradiographs
A aummber of autoradiographs of the tibiae
and femurs of 1 chick, 4 pigs. 1 rvoster and 2
chickens were prepared both at the LSNRDLI
and at the Argonne National Laboratory
(ANIL) to determine the pattern of deposition
of fission products. Contact printing on A-ray
no-serees filam was found to be the most satisfactory method of preparing the antoradiowyaphs. The discussion and conclusions pre-
sented below summurize.the findings reported
by Norris (14).
The antoradiograph of a tibia from a chicken
sacrificed at 45 days post detonation (Fig. 5.2)
indicated a relatively uniform distribution of
the activity throughout most of the bone, with
the highest concentration of activity in the area
adjacent to the epiphysis. This area of high
activity corresponds to an area of dense trabe-
cular bone.
)
The tibia and femur of a baby chick, which
died spontaneously 47 days post detonation,
showed the heaviest concentration of radioactive riaterial in the diaphysis (Fig. 5.3). The
end recions of the bone, which were laid down
after the antmals were removed from the contaiminated environment, were relatively lacking
inactivity. The reeion of rreatest activity was
li the diaphysis, which appeared to be ab-