See
Graph Four shows the number of microcuries of fission products in_ gested at times after detonation to produce 1.0 rad to-the thyroid.
IiI. Doses to the Bones
The three principal bone-seeking isotopes of concern are gr? - Y,
: 89
140
140
Sr“, and Pa
-I1a
.
Evaluation of these may be made in terms of amount
deposited in the bones versus maximm permissible body burdens, or in rads
of dose that they deliver after deposition.
Since values for maximmper-
missiblé body burdens are based on the concept that these will be maintained
.
indefinitely in the body, they are not so valid for sr°9 and patt0_ la
140
when considering short periods of emergercy intake.
‘
The following principal assumptions are used in calculating the
‘doses to the bones of adults:
a.
The percentages of the isotopes of gr??? or, and palOte
140
in mixed fission produste are according to Hunter and Ballau.?
b.
The percentages of intake of these isotopes that are deposited
“in the bones, the energies of emissions, and their effective half lives
are according to reference five - except for sr90 where a 27.7 year radiological half life is used here. c.
The mass of the bones is 7,000 grams. -
~
The method of calculation of doses to the bones is {]lustrated by
“computing the dose from er°? from the intake of 27 microcuries (See IV Discussion below) of mixed fission products on the 120th hour.
-culatiors were made for gr20 -y90 and Ba
1k0o
-6-
-La
iho
Bimilar.cal-
and then the three doses
_ DOE ARCHIVES