TABLE 11
RECOVERY OF KNOWN
.
Sumber
oo
AMOUNTS OF PLUTONIUM FROM REGULAR AND MOCK URINE SAMPLES
) Determinations
Nature of Samples
94
88-100
Mock urine solucion
93
85-101
ra
Regular urine
88
73-104
}
Regular urine
95
81-105
‘
Mock urine solution
11
MPLE
29.
In a fur-
Health Pass Ward for sample collection.
eogae art.
4
2.2
4.3
to reduce costs, the Health Pass Ward
ther «tfort
wan abolished
to collect
in 1951, and employees were asked
at home 2 morming and 2 evening void-
These samples were pooled and considered
inys.
3.4
the “equivalent' 24-hour urine sample.
O.1
2.2
A reusable
. exposures
), and this
able IT)
nformation
of
fore,
The metal kits proved eventually to be
There-
a disposable cardboard kit containing four
ay health
ted to the
ote = AEERa cage©
procedure
tion per minute.
In 1955, an alkaline earth phos-
phate precipitation was used directly on urine
samples to concentrate plutonium, eliminating the
Need to evaporate large volumes of urine.
This
recoveries or blanks.
ysis of samples collected by this means suggests
The desire for greater sensitivity resulted
that a “true'�� 24-hour sample is not necessarily
in adoption in 1957 of the Hanford procedure.
collected.
this method, plutonium is separated by TTA extrac-
The pooled samples represent the urine
In
voided over a period of 22 + 4 hours when collected
tion, and the final radiometric measurement is made
correctly.
by NTA (nuclear track alpha)
This collection procedure is used today.
film counting.
The
Hanford procedure afforded plutonium recoveries of
been collected in special containers with time marks
70 + 17 percent with blanks of 0.007 + 0.005 dis-
on the lids in an effort to learn more about the
integration per minute.
constancy of plutonium urinary excretion.
chemical separation procedure utilizing anion ex-
Informa-
A somewhat simpler radio-
tion gained from analysis of such timed samples has
change was substituted in 1963.
made it possible to apply corrections by volume and
electronic equipment capable of pulse-height dis-
Introduction of
specific gravity so that results expressed in dis-
crimination made it possible in 1967 to include a
integrations per minute per sample can be realis-
step utilizing 2365, as a tracer or yield-determiner.
2
In June 1972,
feo was substituted for 23654 to
23854 and 239-240), |
reduce the background in the
corrected to disintegrations
per minute per
regions.
ami
¥ ap-
phosphate-lanthanum fluoride co-precipitation tech-
l-pint bottles was introduced in January 1958; a
dav,
ANCES
counter
By 1949, the serial bismuth
statistical review of the results obtained by anal-
the early
per min~
tion per minute.
change in procedure did not alter the measured
tically
ecovery
Suggest that plutonium recovery was 82 + 19 percent
associated with blanks of 0.69 + 0.53 disintegra-
20 percent with blanks of 0.15 + 0.1 disintegra-
l-pint bottles, which were discarded
Since 1969, occasional nonroutine samples have
em of
Existing data from that time
tained three
ings in three bottles proved unacceptable.
is been
cupferride complex.
nique was in use, affording recoveries of 67 +
after use.
our samples
an after a
plutonium separated by co-extraction with an iron-
metal kit was furnished the employee; each kit con-
unsanitary, and the concept of collecting 4 void-
ght voidings
zh bathing
(O-1.2 cpm)
(average 0.5 cpm)
Blanks (regular urine)
le (cpm
ospital
Spread
:
(4)
Recovery
;
(A)
Amount of Spike
(cpm)
f
The procedure, in use today, affords an
RALTOCHEMICAL SEPARATION METHOD OF URINARY ASSAY
overall recovery of 80 + 20 percent as determined
FOR PLUTONIUM
by internal spiking with
To the best of our knowledge, as of January
1944, urine samples were ashed and the alpha activity of the ash was measured directly.” However,
we
knuw that in 1945 urine samples were ashed
and the
RADIOMETRIC MEASUREMENT
The measuring device used in 1944 was a gas
flow proportional alpha counter of unknown efficiency
25