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RADIATION STANDARDS, INCLUDING FALLOUT
discuss these things tomorrow will give you much more detail on
that. That is one type of approach.
Another approach is looking for possible tracers in the very large
scale detonations, the two large ones of the Russians. We may be
able to trace them quitespecifically.
In our own tests in the Pacific, tracers have been introduced into
certain of the devices so that we can get very good followup data as
to where the material from any particular device goes and how long
it stays in the stratosphere and where it comesout.
Representative Price. Do you expect the 1962 spring fallout measurements to throw any further light on the situation mvolved in the
Soviet 60-megaton test?
Dr. Dunnam. I think we will learn a great deal aboutit, definitely.
Representative Price. Have you had problems in connection with
this so far?
Dr. Dunuam. The problem has been only to gear up fast enough.
Wehave had a tremendous amount of cooperation from everybody
whom we have asked to help onit.
Representative Pricer. You mention at certain levels of cesium 137,
humans-tend to lag behind the milk level by about 6 months. Would
you explain the reason for this more fully ?
Dr. Dunuam. Dr. Langham can probably give you a better answer. It is my understanding there are two factors here. One,
cesium is more in meat than it is in milk and consequently a large
part of the cesium comes into the diet late because meat is held before
it is eaten. The other factor is that the body turns over cesium
relatively rapidly, about 100 days half-life in the human body, and
it takes a while to reach the equilibrium level.
Representative Price. On the figures of the amount of strontium 90
in the milk supply, and so forth, as a result of previous fallout, are
they far below the permissible level?
Dr. Dunuam. Yes; I think they have been well below the permissible level.
Representative Pricz. How far below would you say ?
Dr. Dunnam. Some of them have gotten as high as 30 to 40 strontium units from time to time. I think the permissible average levels
for a year for the population as a whole as recommended by FRCare
66.
Representative Price. The mere presence of any strontium in the
bonestructure of a child or adultis hazardousitself. It is the presence
of any strontium.
Dr. DunHam. Certainly no more hazardous than the normal amount
of radium in people’s bones. The strontium is not natural but it is the
same sort of thing. It doesn’t necessarily mean certainly in any given
child that it is going to cause serious trouble. It is a matter of degree.
Chairman Hotrrierp. You spoke of radium being in the natural
bones of a child.
;
Dr. DunHam. Yes.
Chairman Hotirrep. What is the measurementthere in relation to
the strontium 90 which has been absorbed ?
Dr. Dunwam. In general the radium content of bones on the average is relatively low. There are certain areas in the country, and I
think Mr. Price knows where I am referring to, in which the local