years of age ingested more activity each daythendidadolescents_andpersona
greater than 40 years of age.
Max imum deviation from the average value of the
daily activity ingestion rate for.menbers of: an.
1 agesubgroup wasno greater than
a factor of 3.
However, the population distributions illustrated a maximum fac~
ae
tor of 5 times the mean activity ingeat ion:vate value. 25:31
nt
ff
pat
,
Dose equivalent rates post return were determined for members from both
oad
atolls.
'
For Rongelap Atoll, the residents received approximate ly 100 to 200
mRem per year during the first 5000 days post return from internal emitters.
The principal contributing nuclide was 137G4,
For Utirik Atoll, the residents
'
‘
received up to [5 Rem per year during the first 400 days post return,
contributing nuclides were 652, and 6000,
1:
Themajor
Dose equivalent rates to the
Utirikese from internal emitters fell below 50Q mRem per year at approximately
.
{200 days post return.
i
*
ran,
oo
i
1.
The dose equivalent for ipopulation subgroups and for individuals was deter:
mined.
Table 6 summarizes the results for the total body, thyroid, red marrow,
testes, ovaries, lower large intestine wall, and liver.
The catenary compart-
~
ment model of Bernard and Hayes (Ber70) was used to determine doses to various
“oNs
segments of the gastrointestinal tract.
Bs
“ol
RS
more radiation dose from
e
4
65
“Zn,
60
The Utirikese received significantly
Co, and
55
“Fe than did the Rongelapese because
e
of short mean residence cimes of these nuclides in the environment.
.
to the Rongelapese were 2.5 time greater and
doses received by persons at Utirik.
137 Cs
re
9055 doses
a
doses 1.5 times greater than
HS
mt
:
ae
This occurred even though Utirik resident<:
hy
. ae
returned to their atoll 3 years earlier and somewhat reflects the degree
Uo
to which Utirik was less contaminated than Rongelap.
51
‘
.
ey
CE ae ee es
Ws
yeaa
SQ +
Meee
ee
nage
a+
1 ARE