-38-
(Table 6) show that the plant tissues concentrated the longlived isotopes e337? and Sr 90
amounts in the soil.
in the soil,
which
were present
Cel44_ py 144 | present in high
accounted for only a small
radioactivity in the plant samples.
in low
amounts
percentage
of the
Analyses were not made
of the radioisotopes later shown to be present commonly in
plant gamples
2x25 -Nb?>,
from this
Ryt06~ pp 106 |
area.
These isotopes,
Co? 7, 69 and Zn©? ,
such as
may account for
the radioactivity that was not determined in the analyses.
Radioactive decay curves of individual
samples
of
these tissues show that the radioactivity was decaying at
a very slow rate.
radiochemical data,
and ¢csi37
This observation is in accord with the
since both sr?°
(half life 27 years)
(half life 28 years)
accounted for the major
portion of the radioactivity analyzed.
DISCUSSION
Previous studies to evaluate the
recovery and rein-
vasion of the flora at the Eniwetok Proving Ground,
mately fifteen months after Operation Sandstone,
in 1949 by St.
John
(22)
and Biddulph (©) ,
approxi-
were made
They reported
morphological abnormalities in ten species of plants growing