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.

Select target paragraph3