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BIOLOGY AND MEDICINE
In an address before the Washington Academy of Sciences, Washington, D. C., November
15, Merril Eisenbud, Director of the Atomic Energy Commission Health and Safety Laboratory,
New York, stated that his estimates of the deposition of strontium 90 in soils are in good agreement with those of Commissioner Libby. On the basis of current concentrations of strontium 90
in milk in the New York area, Eisenbud estimated that 8 micromicrocuries of strontium 90 per
gram of calcium becomes the upper limit of the foreseeable strontium burden in the skeletons
of the population of that area, and that 25 micromicrocuries of strontium 90 per gram of
calcium is the highest foreseeable skeletal burden anywhere in the United States from weapon
tests already conducted. Eisenbud qualified the estimate with the statement, “This estimate is
likely to be reduced as new information about the uptake of strontium 90 eliminates some of the
uncertainties which have prompted the use of highly conservative assumptions.” (End of
UNCLASSIFIED section.)
Radiological Marine Biology Survey (aR
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A survey to determine the amount of radioactivity in the waters around Bikini and
Eniwetok Atolls was made during the period June 11—21, 1956, from on board the USS Walton
(DE 361). The 3,300-mile cruise covered a grid of 53 sampling stations about 45 miles apart,
lying between 10° 15’ and 14° North Latitude and between 159° and 166° East Longitude, within
the restricted zone established for Operation REDWING,
Radioactive materials were found in the plankton samples from every station. The highest
plankton counts, 1,100,000 disintegrations per minute per gram (d/m/g) wet weight, were obtained near Bikini Atoll, and the lowest, 1,300 d/m/g, in the northwestern part of the survey
area. The average value of 71,000 d/m/g for plankton was about 7,000 times the average
value for surface water.
Water samples were collected at the surface and at depths of 25, 50, 75, and 100 meters.
The average radioactivity of water was 10,000 disintegrations per minute per ter (d/m/1) at
the surface and 3,900 d/m/1 at 100 meters. A scintillation probe was used to record con-
tinuously the radioactivity of the surface water. This method has interesting possibilities if
problems of contamination, vibration, and static electricity can be overcome. The survey
successiully demonstrated the usefulness of the various methods in evaluating the amount
and distribution of radioactivity in the sea.
The above values for plankton and water are of the same order of magnitude as similar
samples from Rongelap lagoon during Operation CASTLE. The only fish collected on this survey were three flying fish in which the radioactivity of the liver sample was about 0.1 that of
the plankton, and the muscle 0.05 that of the liver.
The second and final open survey operated from on board the USS Marsh (DE 699) between
Kwajalein, Eniwetok, and Guam. The 4,000-mile cruise was expected to be completed about
October 1, 1956. (End of Cis section.)
Aerial Monitoring —Operation REDWING es
The use of fast moving aircraft to delineate fallout patterns was successfully accomplished
during Operation REDWINGin support of Task Force fallout studies. P-2V aircraft equipped
with the aerial monitoring equipment designed by the Health and Safety Laboratory of the New
York Operations Office mapped tens of thousands of square miles of open ocean after each of
the large detonations. Equipment employed during REDWINGis presently being considered by
the Federal Civil Defense Administration to meet state requests that aerial radiation detection
instruments be supplied on a matching fund basis as part of the national civil defense program.
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