additional discussion and clarification (Leggett
et al., 1982; Cristy et al., 1984). Doses listed in
this paper are calculated from the Leggett
model.
Transuranic Radionuclides (239+240Py
241Am)
Ingestion.
When
with
the
s&rface
soil
potential effective dose from 137C§ and %Sris
about 3 orders of magnitude less than
239+240 Py and 241Am.
and
that from
The same conclusion can bej reached by
looking at the recent publicafion of the
National Radiological Protectiqn Board in
England (Kendall et al., 1986).
[he effective
We calculated the effective
dose from ingestion of transuranic radionuclides
_ (29+240Pu and 241Am) by ICRP methods (ICRP,
1979, 1986, 1988).
combined
concentration of the radionuplides, the
dose per unit intake for inhalation|(in Sv Bq-1)"
is 5.7x 10-8 for 90Sr, 7.7 x 10-P
1.1 10-4 for 39+240Py, and 1.2 x 14
The amount of ingested
plutonium or americium crossing the gut wall to
the blood {i.e., the gut-transfer factor) is
assumed to be 10-3 for plutonium and americium
in vegetation, and 10 and 10-3 for the fraction
of Pu and Am, respectively, ingested via soil.
Of the fraction of plutonium or americium
reaching the blood, 45% is assumed to go to bone
doses via inhalation are so small for 137Cs and
biological half-life is 50 y in bone and 20 y in
liver for both elements (ICRP, 1986). The
quality factor is 20 for the alpha particles from
ZB9Py 2A0Py, and 241Am.
Inhalation. The effective dose from
inhalation for the transuranic radionuclides is
based on the intake determined from the
assumptions discussed in the section on
Airborne,
Respirable
Radionuclide
Concentrations of this paper and ICRP dose
methodology (ICRP, 1979, 1986, 1990). The
The estimated effective} dose from
ingestion of natural 2!0Po and 219Pb is based on
particles, and the quality factor is 20. Other
parameters are described in the ICRP method
previously discussed for the ingestion of
transuranic radionuclides.
The activitymedian aerodynamic diameter (AMAD) is
determine the body weights of fhe Marshallese
people (Conard et al., 1958, 1959, 1960, 1963,
1975; McCraw,1980; Miltenberggr et al., 1980b).
The average body weights of adult males are
listed in Table 9. The average aflult male body
weight is 72 kg for Bikini, 71
for Enewetak,
63 kg for Rongelap, and 69 kg or Utirik; thus,
they are very near the 70 kg value of reference .
man (ICRP, 1975). (The lower Body weight for
Rongelap could be because of age distribution.)
Wehave used 70 kg as the average male body
%Sr that they are not listed in th¢ tables.
Polonium-210, Lead-210
and 45% to the liver (ICRP, 1986, 1988). The
new ICRPdata and methods (Ecferman, 1993).
The weighted committed effectiv@ dose per unit
intake of activity for 210Po is 2.3 10-6 Sv Bq-l.
The corresponding weighte@d committed
effective dose for 21Pb is 1.5 x 1096 Sv Bq-l.
Body Weights and Biologidal Half-Life
of 137Cs
239+240Pu and the 241Am are considered class W
assumed to be lum.
Data from BNL have been summarized to
This is a conservative
approach in that measurements at Bikini Atoll
' indicate the AMADis between 1.5 and 2.4 pm.
The potential effective dose from the
inhalation pathway for 137Cs and 99Srat the
atoll are insignificant compared with the
transuranic radionuclides. For example, the
annual limit of intake (ALJ) listed in ICRP
weight in our dose calculations. The average
body weight for 113 aduit Females in the
Enewetak population is 61 kg. [it is 67 kg for 13
Utirik females, 66 kg for 41 Bikini females, and
54 kg for 83 Rongelap femaleq The weighted
average for females is 60 kg.
The average biological Balf-life for the
long-term compartment for 1{7Cs in adults is
publication 61 (ICRP, 1991b) is 106 Bq
(2.7 x 107 pCi) for 137Cs, 5.9 x 105 Bq
(1.6 x 107 pCi) for 99Sr, and 3 x 10% Bg
(8.1 x 103 pCi) for each 239+240Py and 241Am.
1 Sv = 1 Joule kg-! = 1
disentegration sec 1 = 27 pCi.
26
rem; 1 Bq = 1