Frank Cluff

ale

The Ad Hoe Committee has recomended certain precautions in planting
peundanmus, nenely removal of contaminated eeil from the area of the

Plants, which ghould significently reduce the radionuclide content of

the Sruit. However, there must be followup studies when thease locally
produced foods do become svailable since the levels will not be zero.

As to dose to children, I have taken what may be a worst case situation
for 13Tcg to see how the dose compares with the value for adults.

I

have used as a reference, "The Half-Tine of Cesium-137 in Man" (Attech~

ment 3) and have considered the improbeble case where the datly 137cs
wi

intake of the 2 year olf is as high as for the adult.

The resultant —

year dose of 276 mrad for the child is not significantly different

from the 230 mrad 5 year dose obtained for adults.

I did not correct

the child's 5 year dose for changes in biological half-time or body
weight that occur over that period sinee the curve in Figure 4 of the
cesium reference indicates that for a given intake the dose rate does
not change much over this range of ages.

Using this worat case

azsumption, I get a total 5 year dose (extermal plus internal) of about
1 rad for the chilé which agrees with the value in Table VIII.

sees

One ccament on the general subject of whole body ani organ dese de-

terminations (such as spleen) and comparisons vith standards for
small groups such as this Bikini population.

The proper standard

for use ag a comperison ts the value for the individual in the Bikint

population. The followup studies by Conard and others will establish
a basis for determining the range of infividual exposures so that there

should not be any surprises.

Thus Oustafson's "Acceptable Intake for

Individuals” in Table VI is the proper ecolwm for comparison with diet

Levels and the dose standard for comparison purposes for whole body,
blocé forming argans, ete. would be 500 mrad per year.

While I don't expect we will learn anything dwring the cleanup operaions that will change Gustafaon's predictions regarding external exposures, it may be vorthwhile to again review the internal exposure
question at the end of cleanup operation, particularly if additional

|

|

oe

|

semples of itema of the diet are taken and analysed end base-line body

burden dats become available. I recommend that review of such data
be a consideration in the AEC determination that the cleanup project
ia ecmpleted and that the atoll is ready far return of the population.

l

The conclusion to be drawn from this exercise and from vorking with

|

|

|

—

available data is that the estimates of internal exposures I have mace
are not significantly different from Dr. Gustafaon's. If anything,

Select target paragraph3