83
N-10
Studies
on intake
by inhalation
concentrated
on
Island
(Shinn
et al 1980).
In
plutonium-239,-240
at Bikini
it was assumed
that
a person
would be
calculating
the results,
exposed
to maximum dust conditions
for
5 hours
per day throughout
life
(tilling
fields),
an unrealistic
assumption
bound to give
very
high
exposures
(tilling
deposits
1.5 x 10-s
picocuries
per hour in
the lungs).
To obtain
(1982b)
that
the
the
was practically
the
the inhalation-dose
transuranic
specific
Island.
of Bikini
Island
Rongelap
dose,
distribution
it
was
of particle
assumed
sizes
et al
by Robison
and of radionuclides
Therefore,
same on Bikini
and Rongelap
Islands.
as the
on Rongelap
would be to that
on Bikini
activity
of Rongelap
soil
(O-5 cm) was to that
Specific
activity
top 5 cm of soil
in 1978
in
Inhalation
30-year
dose
to
bone marrow c/
rem
pCi/g
Bikini
a/
plutonium-239,-240
americium-241
Rongelap
b/
plutonium-239,
americium-241
a/
b/
c1
-240
11
8.7
.033
.035
3.2
1.0
.010
.005
Robison
et al (1982a,
pp. 8, 12, 44, 56).
Robison
et al (1982b,
pp. 12, 14, 47, B1O, B13).
The dose throughout
the bone would be about
4 times
The
a factor
period
to be
dose
is greater
for
a growing
child.
of 2.8 to convert
the adult
inhalation
rem).
0-30 years
(.042
The dose to the
about
2.5 tines
that
to the marrow.
as
great.
Robison
et al
dose to that
adult
lung is
(1982a)
used
for
the age
considered
Dr. Robison
(personal
communication,
1988)
has reviewed
these
dose
ICRP factors.
estimates
according
to the more recent
lie has reduced
dust
consumption
by a factor
of 3.5,
which would reduce
the dose
proportionally.
This
is still
a liberal
allowance
for every
day of life
to death,
but in any case
a much more reasotile
one.
The net
from birth
result
is a reduction
in dose for plutonium
by a factor
of about
3, and
for americium
by a factor
of 4.