the Bikini Island options.
inhalation rate in pCi/da.
The Eneu
A mass
living pattern, therefore, has more
loading of 100 g/m? is at the high
flexibility for potential exposure via
end of the observed range for normal
other pathways without exceeding Fed-
open air aerosol measurements.
eral guidelines.
ever, since local resuspension created
How-
in the immediate vicinity of an indi-
INHALATION PATHWAY
vidual during his normal activities
No air sampling data were taken
Open
measurements, it appears reasonable,
field aerosols were measured to some
for lack of specific data, to use the
extent previously at Bikini Atoll. 8°27
higher number.
Because of the sparsity of data, how-
concentrations in the surface soils
ever,
(O to 5 cm) of Bikini and Eneu Islands
and also the lack of data on
The average 239, 2405,
resuspension processes in the atoll
are 9.3 and 1.4 pCi/g, respectively.
environment, the average concentra-
The pCi/day intake resulting from the
tions of Pu in the soil were used in a
above model is, therefore,
mass loading model to predict the
Bikini and 0.0028 for Eneu.
0.019 for
The doses resulting from inhalation
doses via the inhalation pathway.
This is the same approach used to
of 241,240, are listed in Table 10 for
evaluate the inhalation pathway at
the three critical organs:
Enewetak Ato11.28
and liver.
The mass loading concept may be
lung, bone,
The doses predicted on
Eneu are, of course,
less than those
more relevant for estimating the
predicted on Bikini Island.
potential dose via inhalation than
doses will be compared below with bone
‘open air aerosol measurements because
and whole body dose from other pathways.
is reflected in open air measurements.
in the soil on Bikini and Eneu is
Therefore, it is assumed that the con-
approximately 10 times that of
centration of Pu observed in the sur-
239, 2405, 3
face soil at Bikini and Eneu Islands
energy beta radiation (0,021 MeV maxi-
will remain the same in the respir-
mum) and a much shorter half life
able, resuspended surface material.
(14 yr) the integrated 30-, 50-, and
In addition, a mass loading of
70-yr doses from 24doy are more than
100 gsm and a breathing rate of
one-tenth less than those listed in
20 m>/da were used to develop the Pu
Table 10 for 239,240,
loas
be
LapeEct
Se
Xgl n tal
eee
ment may be significantly greater than
Two other isotopes must be consid24tn
ered in the inhalation pathway —
241 Pu
24.an.
and
The concentration of
at dniotaanee
These
Ans
Lehele
ek a
aer A oe Ped ae bo
ee
during the 1975 Bikini survey.
is probably greater than open air
the resuspended material created by a
person in his own immediate environ~
90099b8
-18-
However, because of low