RADIATION STANDARDS, INCLUDING FALLOUT
133
Dr. Caapwicx. In terms of the other materials it is considerably
longer. Of course, by the same token, the other materials do not tend
to showthe kinds of wide variations from day to day or even month
to month that iodine 131 shows.
The fluctuations in strontium 90, for instance, tend to be very much
less. They are much more gradual, whereas the iodine, by virtue of
its short half-life, shows very wide variations.
Representative Price. Has there been any area of the country so
far where the fallout has been considered to the point where you even
thought about the necessity of stopping the milk consumption ?
Dr. Cuapwick. No, sir; it has not. As indicated in the paper submitted for the record, “Intake of Iodine 131 by U.S. Population,” table
II, which shows estimated thyroid doses to infants, even the highest
values for estimated thyroid dose were below the annual RPG of the
Federal Radiation Council.
Representative Price. We frequently read press stories as to the
extent of fallout in given areas.
.
Would you care to comment on the significance of the period of
high dosages? For instance, the most recent one was in the Midwest.
Dr. Cuapwick. The significance of any daily value can only be
evaluated in terms of what you expect the annual average to be. This
is particularly true for the case of iodine where the total amount of
radiation dose from any given activity is delivered over a very short
period of time.
So the only way that one can make any evaluation of these high
values is on the basis of expectation and predictions as to what the
annual accumulated doses are going to be.
Chairman Howirirtp. You see where we get a lot of excitement
and a lot of fear is because a headline will say, “Radioactive Iodine
Found in Milk Doubles That of Previous Measurements.”
They may be talking about a millionth of a millionth of a curie goes
to twenty-millionths. But the word “doubles” indicates to the per-
son who does not have access to the annual average that here is something thatis startling and this makes a headline and it scares the
mothers to death. and they cancel their milk orders.
In a case of Minnesota a year or two ago, even the purchase of
bread fell off because of a headline which was taken completely out
of context of its scientific meaning. But this is something you can't
control] and wouldn’t control in a free society.
But it does cause alarm. Oneof the reasons for this committee’s
hearings is to try to put these values in proper perspective so that at
least people who want to be informed can be informed on the relative meaning of these headlines.
Representative Prick. Dr. Chadwick, you state that range TIT
could occur without exceeding the average annual rangeTT intake.
Is this not a rather confusing form of guidance for the public/
Dr. Crrapwick. Of course, the Federal Radiation Council guidance
reallywas not addressed to the public. In other words, the guidance
was directed to Federal agencies with responsibilities in radiological
health to give them some basis for the kinds of actions which onght
be appropriate in the situation of different transient rates of intake.
T suspect that it is somewhat complicated, but T am not sure 1 know
exactly how it can be simplified.
In other words, it is a matter of
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