SECTION I
PHYSICAL DECAY OF SAMPLES FROM ENIWETOK ATOLL IN 1952
INTRODUCTION
Previous decay studies (UWFL-53) of the biota and other materials
from the Marshall Islands
have
covered periods
up to nearly three
years following the detonation of atomic testing devices.
The earliest
curves (AECD-3446:27) were for oyster, XE-19, and ovary of damsel-
fish, XE-40, whose slopes from 20 to 800 days were -1.6.
Decay of 83 samples from Rongelap Atoll (UWFL-42:46) over a
period of from 38 to 500 days following March 1, 1954 averaged -1. 4.
Coconut milk was most unusual among these,
having a decay rate of
only -0. 24.
Decay data for samples collected in 1952 offer the most compre-
hensive picture of long-term decay trends that may now be contributed
from studies by the Laboratory of Radiation Biology.
proximately seven years is involved.
A period of ap-
These samples number 102, of
which 96 were from Eniwetok Atoll collected within 10 days after the
Mike test,
6 were within 10 days pre-Mike and would be referred to the
Greenhouse series.
In addition there were 2 Nevada sand samples
col-
lected on November 29, 1951, related to the Uncle-Jangle atomic tests,
making a total of 104 decay curves.
-l-