Proyect Number
6 Battelle
Pacific Northwest Laboratories
Date
September ll, 1984
To
W.
From
R. C. Thompson
Subyect
DRAFT LETTER TO ROGER RAY
Internal Distribution
410006
KR
J. Bair
The following scientists met in Richland, WA, on August 28, 1984, to
review the current status of predicted and actual exposure of Marshall
Istanders, particularly as these might relate to potential resettlement
of Eneu Island in the Bikini Atoll.
Bair
Eckerman
Healy
Lesard
Ray
Robison
Templeton
Thompson
Comparisons presented of measured vs predicted levels 9f,7°7Cs in
Marshall Islanders showed very good agreement.
Since
Cs is
estimated to contribute 85% of the total exposure from fallout radio-
nuclides in the Marshall Islands, this agreement between measured and
predicted levels constitutes an important overall validation of models
employed in the predictions -- including physical, biological, and
cultural aspects of these models. The accumulation of data in recent
years would seem to remove any reluctance, as previously expressed by
EPA, to apply applicable U.S. limits to the Marshall Islanders.
An area of remaining uncertainty relates to the transuranic elements,
principally plutonium and americium, where very limited bioassay data
on plutonium excretion are in gross disagreement with model
predictions. This is not considered a serious complication because the
transuranics are not predicted to contribute importantly to the total
radiation dose, and analytical problems seem to offer a plausible
explanation of the bioassay problem. This problem is being intensively
studied and a resolution may be anticipated within 3 to 6 months -perhaps sooner.
Based on the best current evidence, it would seem unlikely that an Eneu
resident, consuming a mix of local and imported foods (but no
significant quantity from the Island of Bikini), would exceed an
exposure of 500 mrem per year.
RCT: pmb
Sa4-1900-001 {3~71)