WwW
The herbivore are obviously the test
concentraters,
-
DONALDSON:
e4y
of what you get from the whole-body count, showing the com-
nw
~
o
parsion of 1957 and 1959.
CONARD:
The next slide I think shows a srectograph
In March, 1957, shortly after they
had come back Showing an increase, the first peak being
otk
We carried out
these whole-body counts over the years since they've been
Dn
cesium-137 and the second peak is zinc-65,
back on the Island and I can now review very briefly what's
19
happened in the way of the body burden of these isotopes.
il
The next slide, please, This®is a histogram that
12
Shows the changes over the years,
13
Shows the higher levels, of course, connected. with the initial
The first 1954 data there
#
14
contamination.and then up until 1957 their body burdens re-
15
- duce practically to zero and then you see on their return to
16
Rongelap the increase in cesium and zinc and strontium-90,
17
of course ,also began to appear, and this had to be detected
18
not by whole-body counting but by urinalyses, radiochemical
19
analyses of the urine.
20
The levels reached a peak about 1961 or so andbe-
el
yond that time they have seemed to be at equilibrium with the
22
environnental levels of the isotope,
23
peaked at about a little less than one microcurie of body
24
burden, which is not high, but it represents @2bout 300 times
25
the level of those of us in the medical team that were counted.
26
Since that time it seems to have remained fairly constant,
aT
In other words, they are taking in just about as much as they
28
are putting out,
29
Cesium, for instance,
In regard to the zinc, it reached a peak at about the
39
same time that the cesium did but suddenly within one year's
31
time it dropped to about 1/10 the previous year's value, and
32
I wonder, Lauren, do you have any comment on that as to why
33
we had this sudden drop in zinc~-65 in the people?
Was
Stafford Warren
DOE/UCLA ¢D