.Fete
ee “i feePT eaateed
RRL
eR ariaeee
Pe seat
ae pee
ea ae, Seip
*
Vee
a
cy
ard ADgyNS
;
ae
r
.
and sex subgroup distributions.
This less pronounced variation may be due tu
“a
the fact that ©> 7 measurements took place over a 3 year interval while 905,
and 1376, occurred over a 23 year interval and thus was contained in a more
homogeneous population than were the longer lived nuclides.
;
ede.
90
Figures 22 and 23a and 23b summarize the
!
uy
~’Sr dose equivalent results for
individuals at Ronge lap.
In this analysis, only the ingestion pathway was considered important,
Some radioactivity would enter the body via the resuspension and direct inhalation pathways.
It is known that for a given soil concentration of ‘the Stable
s
*
naturally occurring analogs to
the radionuclides
considered here, the ratio:
:
5
|
*
i
of food and fluid intake to blood relative to airborne intake to blood, are
as
follows:
Co > 3000
Zn > 130
Fe > 550
Sr > 10,000
a
Ce > 400
Thus, dietary intake of radioactive material is the principal pathway leadiig to
internal deposition,
This applies to most nuclides in the environment, howrver,
there are notable exceptions including I, U, and Pu.
External Exposure
ag
A value of .73 rade in tissue of interest per rontgen, measured in air at
.
A
one meter above the surface, was used to convert exposure in air to absorhei dose
in tissue.
The source was assumed to be an exponential distribution of
tivity with depth in soil, typical of aged fallout (Be70).
137,
ae
Because of the
multidirectional nature of the source, variation of absorbed dose with depth of
organ was minimal.
Additionally, external doses were adjusted for living pat 43
mo