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various vones in the given individual‘s body which ppens
to te samplec,
However s the specific concentration © the
strontiun-S0 deposited will not exceed that in new . ne
developed entirely in the present oiological enviro: rent,
ies., the local concent ration jn adult bone will not exceed that for the whoie bone in young children, wnose total
bodies are composed of the mixture of strontium-90 and
calciurn which now is present in food.
Since the present
ratio for children to adults is about rour to one for
averege totai strontium-90 content, the factor of concentration in adults! active bone regions may be? as mucn as
four-fold greater than the whole body averége.
Thus the
apparent spread for random bone samples taken from adults
sheuld be very large compared to the true equilibrium
soread for these reasons.
As equilibrium is approacned,
however, the spread must decrease very, very markedly.
The data on human bones indicate a very wide
scatter, but it seems extremely clear that the variation
is & rerlection of the fact that the main skeleton cof
aduit individuals is net in eg vilibriun with the present
Tood supply, and that tne variations reflect the dirferent
rates at whicn the various bones in the bodies of irnvivicusls are coming into equilibrium with the food suopiy
in the general biological environment. A study of rnole
skeletons taxen from one given locality which is nov under
way as a part of Project Sunshine will clarify the point
about the variztions among individuals in their rate of
coming into equilibrium with the general biological cenvironment.
This study is under way in Dr. Kulp'ts laooratory.
% should appear from these studies that the
variation from the mean of adults will be larger than the
actor of cne-third which apparently is normal for the
types cf equilibrium distribution considered above.
It
is, of course, very important to establish the truth of
vhis prediction clearly. However, the general agrecment
in shape of the distribution curves Tor such widely dite
Yerent materials as normal potassium in whole bodies,
redium, and normal elementary strontium in fragmentavy
human bone, and actual fallout radioactive strontium in
the whole bodies of stillborn chiicren, give us good rea-
".son.to believe that there is nothins extraordinary in the
wi
“
distribution of radiostrontiun in human bone.