BASES FOR CALCULATION OF RISK ESTIMATES USED IN
“THE MEANING OF RADIATION AT BIKINI ATOLL”
I.
ASSUMPTIONS
Estimates of cancer and birth defect risks for the Bikini populations
were based on a number of assumptions.
sulted from consultation
Some of these assumptions
re-
with other scientists including members of the
BEIR committees.
1.
Risk coefficients
not been accepted
from BEIR-I were used because BEIR-111 had
by any U.S. government agency.
We elected to use the
values as given in BEIR-I rather than the revised values based on increased
age of the population
shown in Table V-4 of BEIR-111.
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2.
For estimates
and the absolute
risk.
of cancer risk both the relative
risk coefficient were used to give a range of estimated
The absolute
cancer incidence,
which is not known for the Bikini population.
3.
I
The
I
1
which is unknown for the Bikini
it is probably less reliable than the estimates
calculated
risk coefficients.
For estimating
dose was used because
increased cancer incidence,
the bone marrow
it was slightly higher than the whole body dose.
This probably introduced
4.
I
gives a high value, but since it is based on
cancer incidence,
from the absolute
,
and is not dependent upon the spontaneous
relative risk coefficient
population,
\
risk coefficient gives a lower value, is less vari-
able with the population
the spontaneous
,, I
risk coefficient
For estimating
a small element of conservation.
birth defects neither BEIR-I or BEIR-111 is very
clear about what is meant by parental dose, thus it is not clear whether
birth defects should be based on the dose to one parent or both parents.
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I
In the latter case, the 30-year whole body dose would be doubled. We
assumed the BEIR-I risk of 0.2% rem was based on both parents being
irradiated.
Also because we believed the risk coefficient
from BEIR-I
,