16.
Bryant, F. J.3 Chamberlain, A. C.3 Morgan, A.3 and
_
Spicer, G. 8. RADIOSTRONTIUM IN SOIL, GRASS, MILK AND
BONE IN THE UNITED KING)0OM; 1956 RESULTS. Journ
Nuclear 6, 22-40 (1957
The results of Sr-90 analysis of soil, grass and s..eep
bone from twelve stations in England and Wales are
given.
The &r-90 in the top & inches of undistyrbed
soil in July 1956 ranged from 1.9 to 10.0 me/xa-,
UE
depending on the rainfall. The Sr-90 activity of
herbage and of sheep bone showed a wider range, samples
from acid hill soils being relatively mre active.
Milk from Somerset had a median activity of 4.% pye
Sr-90/g Ca in 1956, compared with 4.1 in 1955.
Humane
bone specimens obtained in 1956 showed Sr-90 activity
depending on age. The average level in children under
5 was 0.7 pue Sr-90/g Ca and the average bone dose 2
mrad/year.
17.
Comar, C. L.3 Wasserman, R. H.3 and Russell, R. Scott.
STRONTIUM-CALCIUM MOVEMENT FROM SOIL TO MAN.
126, 485-92 (1957).
Science
ia
wnat
Radiostrontium moves similary to calcium in food
chains, is well absorbed by plants, animals, and man}
is deposited and retained in bones; is transmitted to
milk and to the developing fetus; and is known to
cause bone tumors and is suspected of causing leukemia.
Megaton nuclesr.explosions result in a large fraction
of Sr-90 formed being deposited in the stratosphere.
This material slowly passes back into the troposphere
with an average residence in the stratosphere of about
10 years. Kiloton weapons deposit their Sr-90 in the
troposphere. Radioactivity in the tropospiisre, regardless of origin, is relatively quickly deposited on the
surface of the earth, primarily by precipitation. The
comparative movement of Sr and Ca in biological systems
is discussed. Finding related to the differential
x
behavior of the two elements are reviewed.
18.
Commoner, Barry
THE FALLOUT PROBLEM.
Science 127, 1023-26 (1958).