the external dose assessment, is based
pandanus fruit and breadfruit,
upon the unmodified conditions for the
pattern III, for example, the total
village island.
terrestrial bone dose is 75 rem, of which
The largest contribution
to the whole-body and bone doses comes
For living
74% is derived from the intake of bread-
from the terrestrial food chain, the ex-
fruit and pandanus, It is important to note,
ternal dose pathway is the next highest
however, that the large contribution to
contributor, and the marine food chain
the bone dose via these fruits occurs only
and inhalation pathway contribute the
when they are grown on northern islands,
least. The relative contributions of each
Pandanus and breadfruit grown on the less
diet component to the terrestrial pathway
contaminated southern islands lead to
dose is shown in Tables 242 and 243.
much lower dose commitments.
Table 245 shows the 30-yr integral
In general, living on JANET, visiting
northern islands, and maintaining
dose for the six living patterns for the
agriculture on northern islands (living
modified soil condition, i.e., where the
patterns III, V, and VI) lead to signifi-
village area has 5 cm of gravel and the
cantly higher doses than if the village and
village island is plowed. Table 246
agriculture are located on islands in the
shows the 5-, 10-, 30-, and 70-yr dose
southern half of the Atoll (living pattern
estimates for the same conditions.
I),
Doses for these same patterns have
Table 247 shows the additional effect
been calculated for 5, 10, and 70 yr and
on the 30-yr integral dose of limiting
are shown in Table 244,
growth of pandanus, breadfruit, coconut,
The most significant contribution via
and tacca to the southern islands, while
the terrestrial food chain is the dose to
Table 248 shows the effect of limiting all
bone resulting from 905, uptake via
terrestrial foods to the southern islands.
The effect of the combination of these preventive measures reduces the dose for
‘As indicated earlier, these dose cal-
living pattern III from 11 rem to 1.9 rem
culations assume that the Enewetak people will continue their current practice of
using catchment rain water for drinking
and that the underground lens water supply will not be a part of their diet. An
indication of doses that are to be expected
from lens water may be obtained from
four water samples taken on JANET in
July 1971. These samples, two each
from each of two 2,5-m-deep holes about
100 m from the lagoon shore, gave average concentrations of 130 pCi/liter for
for living patterns I and III relative to the
concentrations were scattered (<0.03, 21,
when the other major isotopes observed
rent purpose, we will assume an average
at the Atoll have decayed away; therefore,
90Sr, and 400 pCi/liter for 15%cs, 239py
<0,03, and 17 pCi/liter) but, for our cur-
value of 20 pCi/liter.
for whole body and from 80 to 4.7 rem
for bone.
A comparison of the 30-yr integral dose
average United States external background
doseover 30 yr is shown in Table 249,
Plutonium isotopes, because of their
long half-lives, will still be present
Tables 250 and 251 are included to show
Using these concentrations, and
assuming an average daily intake of
100 ml of lens water, the resulting 30-yr
the predicted doses from plutonium to
the three major receptor organs (lung,
doses would be 0.83 rem due to 9 Sr,
liver, and bone) via the three relevant
0.019 rem due to 137%Csg, and 0.00082 rem
due to 239py,
exposure pathways.
II-60