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Part VIII
Biology and Medicine
PROJECT SUNSHINE (UNCLASSIFIED)
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To disseminate the most up-to-date knowledgeof fallout and radiation effects, Commis‘sioner Libby presented a review and analysis of available data in a speech delivered on |
March 27 before the Swiss Academy of Medical Sciences Symposium on Radioactive Fallout.*
Monitoring and sampling programs to study the distribution of radioactive fallout continued during the January-March quarter, as did research on the biological hazards of fallout. The results of analysis of some of the samples collected are given below. a
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Stratospheric Monitoring
The preliminary results of analysis for strontium 90 of some> of the stratospheric sam--
ples collected during the period November 1956 through November 1957 are summarized in
ne
Table 1. Progress was made in tests of filter efficiency but it was still not possible to interFN aM ee
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Table 1— Average Concentrations of Strontium 90 in Stratospheric Samples Collected
November 1956 through November 1957*
Based on Data Available through April 14, 1958
{Strontium 90 content expressed in disintegrations per minute per 1,000, cubic feet
of air, reduced to standard conditions)
‘Panama Canal Zone
Minneapolis, Mino.
Altitude
(feet) 90,000
_ 80,000
65,000 |
. 50,000 |
Average
strontium 90
content
45 +4 24t
23415
45 +37
1948
- San Angelo, Tex.
France Air Force Base
|
Southern Hemisphere
Number
of
samples
Average
strontium 90
content
Number
of
samples
Average
.
strontium 90
' content ‘
Number
of
samples
Average
* strontium $0
content
|
3
7
12
6
15412
28 +13
62431
644
8
8
7
6
<3
28219.
88 + 72
-
1
3
3
0
22 +19
34414
30 + 12
342
Numbe
of
sample
_
:
oT
10
8
2t
* Analyses have not been completed on all samples collected during this period. The Program calls for one sample a month from
eachaltitude at each location. In some instances the sample was not recovered.
t Range shows one standard deviation above and below average. Standard deviations shown include both errors of measurement +
variations in strontium 90 content from month to month.
t These samples were collected within the troposphere (below the stratosphere). The 50,000-foot eimplingI
level is usuaily below f
the etratosphere at this location.
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~* Copies of. Commissioner Libby’s talk entitled ‘Radioactive Fallout”? were provided to the Joint
Committee. The document includes tabulations of recent data and bibliographical references to recent
contributions to the subject.
UNCLASSIFIED
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