~
>
wet KS
on wh
vaieetegone tats 2S cecemeanate
1 eras. Sakae ey elle awnelin me he
-4-
where
fwa
= fraction of ingested Sr% which is retained by
Io
= pe of sr ingested in U.S. = 6 x 10! kg x
' poedy.
Assume 0.3 (From reference 4).
sr™ content of milk (assume 1 ype/ke) (See
reference 5).
Teff
2 bh,
o
=
ore
jab ¥4
= 604 x 10? days.
% E(RBE)N
bone
= 1.1 (See yeference 6).
_ uw Mt
~
2330 9%
t
= 35 x 365 days.
Based on average life span of
m
=7x10 grams for an average adult.
70 years mimus average age of population, 35 years.
1h x 0o3 x6 x10 x1 x 6.4 x10 x 1el x 0675 x 107°
7x10
= 106 rens for 1 pye/ke of sx? only for l year.
But since sr
cannot be kept free of Y%, which has a half life of 65 hours and would
therefore come to equilibrium rapidly (400-500 hours) compared to the
exposure time (t) of 35 years, we mist repeat the calculations for Y™
dose.
However, since the only difference in the two calculations is the
value for ZB(RBE)p for Y™” of 4e4 as opposed to that for sr”? of 1.2,
therefore
if sr dose
the Y* dose
totel dose
> fale
a5 tN ny
Then the equation becomes:
Drens
.
1x 10° rens
hel x 10° rens and the
ee eersteae ae
544, x 10° rens/1 pye/ke of Sr? in milk, or
|