The average adult male Rongelap body-burden for CS-137 rose 561 from
-.
6.7KBq (0.18 uCi) to 10KBq (0.28 uCi) during the interval July 1981 to June
1982.

The mean adult female CS-137 body burden increased 11% from 6.9KBq

(0.19 vCi) to 7.lKBq (0.21 BCi); the male adolescent body burden remained at
6.3KBq (0.17~Ci); the female adolescent body burden decreased 15% from 9.3KBq
(0.25 vCi) to 8.lKBq (0.22 vCi); for male children it increased 9% from 4.OKBq
(O.ll PCi) to 4.4KBq (0.12 uCi) and for female chil&n
3.5KBq (0.093 PCi) to 6.3KBq (0.17 vCi).

it increased 82% from

Overall, the population exhibited a

1.8% per month rise in CS-137 body burden during the.July 1981 to June 1982
interval. This follows an apparently constant body burden (0.0% per month
rise) of CS-137 during the previous twenty four month interval, August 1979 to
August 1981 and a constant declining body burden from the early 1960’s until
1979 (see Graph One).

This recent increase may have resulted from the

relaxing of>restrictions to the northern islands of Rongelap Atoll as a source
of coconuts and coconut crabs.

A summary of the Rongelap Atoll residents

June 1982 average CS-137 body burden is given in Table Two.
The effective dose equivalent rate on July 10, 1982 from gamma emitters
was estimated for various average body masses (see Table Three) for persons
residing at Rongelap Atoll.

These body masses represent the mean body mass of

the adult, adolescent, and juvenile groups. The nuclide CS-137 contributes the
greatest portion of the total effective dose equivalent rate.

The effective

dose equivalent rate frcm CO-60 and Bi-207 was estimated to be less than
5X1O 9 ‘Sv a-l (0.S mranper

year) and was based on the minimum detection limit

of the direct whole-body counting system.
tracted) extern~

The net (natural background sub-

effective dose-equivalent rate

2

is

also

reported in Table

Select target paragraph3