OFFICIAL USE ONLY
that destructive changes might have appeared in the thyroid if these
patients had survived.
However, the evidence from other studies strongly
indicate that if any pathological effects were to be noted in the
thyroid after an exposure of some 10,000 reps they would be minimal.
Likewise, the possibility of serious damage to other organs of the
body, such as parathyroids and trachea which are simultaneously exposed
“SEED mK
to the 131saiations, would be exceedingly smell.
On long term effects, two summarizingstatements may be made.
"No thyroid neoplasm was found which could be attributed to yi3iin @)
after doses to normal thyroidsnjyning into many tens of thousands of
reps and after periods of vbservation up to more than eight hundred
days. "In a series of over 400 patients treated with radioactive
todine at the Massachusetts General Hospital during the past ten years
¢
no ky..o carcinoma of the thyroid attributable to this agent has de_ :¢loped.
Definite answers to the question of carcinoma formation must
await prolonged observation of treated patients.”
131
treatment dose of I 3
23
Here the average
was 10 millicuries and of 713° 25 millicuries.
3. Bones
It is recognized that the intake and deposition of strontium-89
and 90 are intimately associated with the calcium in the diet.
Whereas
it has been assumed here that a fixed percentage of the strontium intake
is deposited in the bones (Reference Five).
It is realized that this
method involves uncertainties, as wuld the necessary assumptions to
generalize for a wide variety of caicium--strontium ratios and intakes
to cover multiple categories.
In situations where doses to the bones
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