Samples of human bone from all over the world and representing all
ages have been collected by Dr. J. L. Kulp (12, 20) of Columbia University
and analysed for Sr~90.
The moat recent data, 1956-57, indicate an
average in small children (a few months to a few years old) of about
0.8 yuo Sr.90/gm Ca.
Samples containing more than three times this figure
have not been reported for this age group.
appreciably lower.
Older ohfildren and adults run
Interestingly enough and not inconsistent with the
milk data from Western Europe the Sr-90 levels in human bone for the
United States and for Western Europe are not very different.
As mentioned earlier, such farm practices as leaving sloping ground
bare to erosion by water or by wind can move the fallout from where it
fell to some place of accumulation.
This, of course, makes for non
uniform distribution in an area.
The vertical distribution of fallout in a soil may be altered by
a