SLIDE 29
Airborne activity intakes were dependent upon
Activity intake by inhalation.
Breathing
the breathing rate of individuals during fallout cloud passage.
conclusion
this
at
arrived
We
rate was assumed proportional to body mass.
based on reference data given by ICRP for persons less than 58 kg (ICRP74).
Adult reference values for breathing rates (ICRP74) were assumed for all
At Rongelap Island, BRAVO debris
Marshallese adults regardless of body mass.
passed during the afternoon, a period of light physical activity for the
population. At Utirik Island, the debris passed during the night, a period of
resting. At Sifo Island a period of light physical activity was assumed in
On the
order to estimate breathing rate during the morning they were exposed.
inhalation
that
qed
basis of urine results and breathing rate, it was determi
Less than 1% of
I.
could not account for the estimated activity intake for
the intake could be attributed to inhalation.
In fact lethal external
exposure rates would have to accompany significant radioiodine intakes if
inhalation was assumed to be the dominant intake pathway leading to the urine
activity excreted on day 17.
ESTIMATE OF INHALED ACTIVITY*
KBaq
Body
Weight
Rongelap Adult Male
Rongelap Child
70
80
890
§20
370
220
410
240
97
55
18
10
110
59
20
12
Utirik Adult Male
Utirik Child
70
30
70
41
—_
_
1200
700
410
230
78
44
410
230
59
35
Sifo Adult Male
Sifo Child
70
30
81
48
85
48
a,:
.
~
85
48
.
4.4
2.5
0.85
0.48
wos
Air concentrations normalized to exposure rate measurements and fallout composition.
31
5.5
3.2
1.1
0.59