Radionuclide Intake
Diet
estimates.
Wewill first discuss the adult diet model
currently used in our dose assessments because
the fetus and infant dose will be dependent on
the intake of radionuclides by the mother.
model, rather than attempt further speculative
Adult (2 18 y)
local
and
from
very
important parameter in the dose assessment;
radiological dose is directly proportional to the
total intake of 137Cs
and 99Sr, which is
proportional to the quantity of locally grown
foods that are consumed at a contaminated atoll.
Therefore, a reasonable estimate of the average
daily consumption rate of each food item is
essential. There is in general, however, a
paucity of data available to develop a diet
model at the atolls.
The diet model we use for estimating the
intake of local and imported foods is presented
in Robison et al. (1980 and 1987). The model
results for the case where imported foods are
available are summarized in Table 1. The basis
of this diet model was the survey of the Ujelang
community in 1978 by the Micronesian Legal
Services Corporation (MLSC) staff and the
Marshallese school teacher on Ujelang; details
of the MLSC diet summary are presented in our
1980 dose-assessment paper (Robison et al.,
1980). This survey is the best estimate of the
current dietary practices of the Enewetak
Data are presented for women, men,
teenagers, and children. Adult intake exceeded
those of teenagers and children, and the intake
of local food was about 20% greater for women
than for men. The higherintake attributed to
women
is
unexplained,
questionable.
uncertainty in
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en
and
certainly
It is, however, indicative of the
acknowledged
cs
refinement.
Our choice of this diet model is supported
The estimated average intake of
foods, i.e., those grown on the atoll,
imported foods, i.e., those brought in
outside the contaminated atoll, is a
people.
Nevertheless, we believe that the
MLSC survey provides a reasonable basis for
estimating dietary intake.
Pending the
availability of empirical data, we have chosen
to use the higher (female) diet for our diet
the dietary
by other considerations. The estimated intake
of coconut is higher in the Brookhaven National
Laboratory (BNL) diet than in our diet model
(Naidu et al., 1980); this difference arises in
part from the fact that the BNL estimates were
for food prepared rather than for food actually
consumed. A more detailed comparison of the
Ujelang diet survey with higher dietary intakes
estimated by the BNL is also discussed in the
1980 report (Robison et al., 1980). When the
estimated body burdensfrom both our dose model
using the MLSC diet and the BNL diet are
compared to actual whole-body measurements of
the Rongelap and Utirik people made by
another BNL team, the MLSC diet predicted
observed body burdensbetter than the BNLdiet
(Robison, 1983; Robison et al., 1987).
In fact,
predictions of body burdens and doses using our
diet model are very close to the whole-body
measurements of the population, as is
illustrated in Table 2.
Further support of our diet modelis found in
the estimates of coconut consumption. The
coconut, at many stages of growth, is the food
product that is of major significance and
dominates the potential exposure of people. The
current estimate of consumption of coconut meat
and fluid in our diet model, which is about 1 to
1.5 coconuts per day per person averaged over a
year, is Consistent with estimates of an average
of 0.5 and 1.0 coconuts per day per person made
by two Marshallese officials with considerable
experience on living habits at outer atolls
(DeBrum, 1985).
Based on data published by
Mary Muari in 1954, the average intake of