-38-
(Table 6)
show that the plant tissues concentrated the long-
lived isotopes Cs
137
90
and Sr~~,
amounts in the soil.
in the soil,
which
cel44_p,144
were present
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 samples
Zr ?>-Nb?? ,
from this
Rut96_pp106 |
area.
These isotopes,
Co? 769 ana 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 cs137
This observation is in accord with the
since both sr 90
(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
in 1949 by St.
John
after Operation Sandstone,
(22)
and Biddulph (©) ,
approxi-
were made
They reported
morphological abnormalities in ten species of plants growing