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4.4

Infant Dosage

The following factors should be taken into account.

The infant

during the first six months may absorb from the gut a much great
fraction of radionuclide than the adult. The residence time of
radionuclide in the body may be shorter than in the adult. For
residence times, the amount retained is diluted by growth.
eats less than the adult.

Jonger

The

@nfant

In the case of cesium-137, which is completely absorbed from

the gut

in both infant and adult and whose residence time is short, the

difference between adult and infant dose factors will be small. [For
plutonium-239, whose absorption by the infant is much greater and whose
residence time is long, an appreciable difference can occur. Hofever,

because the transuranic contribution to the adult dose is so smajl, even

if it be increased very appreciably in the infant, it will not

necessarily be quantitatively important.

Balancing these variables against one another leads to the following
committed dose factors (rem per picocurie daily intake) for wholb-body
exposure:
Radionuclide

Factor at specified age (rem/pCi/day)
O-1yr

Cesiun-137
Strontium-90
Transuranics

5 yr

10 yr

0-10

ye

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