days, respectively),
these patients did
not receive the highest total doses.
Less than a month after the moribund
patient (HP-11) at Rochester had been
injected with 5 micrograms of plutoni-
um (on March 13), Langham had writ-
ten to Bassett, saying:
Your letter of February 27 regard-
ing Hp 11 was startling, to say the
least. The specimens have already
arrived and I am making prepara-
tions to analyze them. . . . In case
you should decide to do another
terminal case, I suggest you use 50
micrograms instead of 5. This
would permit the analysis of much
smaller samples and would make
my work considerably easier. I
have just received word that
Chicago is performing two termi-
nal experiments using 95 micro-
grams each. I feel reasonably cer-
tain there would be no harm in
using larger amounts of material if
you are sure the case is a terminal
one.
On March 27, Bassett replied, saying
that “this case did turn out to be termi-
nal, but at the time I started the experi-
mental period, there was sufficient un-
certainty regarding the outcome to
make me feel that the dose should be
within the range of tolerance.” He
added that “if a suitable opportunity oc-
curred and if you are very anxious that
I should carry it through, I will see
what can be done [about a 50-micro-
gram dose in a terminal patient].” The
opportunity never occurred.
The Chicago scientists also studied the
gastrointestinal absorption of plutonium
by having, on May 13, 1946, six male
employees of the Met Lab drink a
water solution containing 0.35
nanocuries (or about 6 nanograms) of
plutonium-239. That amount was about
a factor of a thousand or ten-thousand
less than the amount injected into the
Chicago patients, so the plutonium ex-
creted in the urine and feces was barely
detectable. Besides measuring the frac-
tion of the plutonium absorbed by the
gastrointestinal tract, the scientists used
the results to improve the interpretation
of plutonium exposure and bioassay
data collected from occupationally ex-
posed workers.
More California patients. On April
26, 1946, Hamilton and his group at the
University of California Hospital in
San Francisco continued their studies,
injecting 2.7 micrograms of plutonium-
239 intravenously in a 4-year-old boy
suffering from terminal bone cancer
(CAL-2). The injection solution also
contained radioactive cerium and yttri-
um. A week later, surgery was per-
formed and significant bone and tissue
samples were taken. The samples were
analyzed for the uptake of the radioiso-
topes and comparisons were made be-
tween normal and tumor tissue. Thus,
the experiment may have been both a
continuation of Hamilton’s 1941 re-
search to find a therapeutic treatment
for bone cancer and a continuation of
the Manhattan Project plutonium me-
tabolism research—the data were ap-
plicable to both studies.
On July 18, 1947, a third person, a 36-
year-old man, purportedly with bone
cancer in the leg, was injected with a
mixture of plutonium-238 and tracer
amounts of other radioisotopes. That
injection was done intramuscularly,
rather than intravenously, and after his
leg was amputated at mid-thigh, the de-
position of plutonium in the bone and
tissue was determined. A month earli-
er, on June 10, a 16-year-old boy with
bone cancer had also received an intra-
muscular injection, but with americium
rather than plutonium. Again, part of
the patient’s leg was amputated and tis-
sue samples were analyzed. Both these
experiments may also have been a con-
tinuation of the bone-cancer research
and were possibly done independently
of the Manhattan Project or its succes-
sor, the Atomic Energy Commission
(AEC).
Such “dual-purpose” research produced
further data for the Manhattan Project
but also allowed physicians to search
for radioisotopes that could be used to
treat cancer. The radioisotopes being
administered would not have any thera-
peutic value for the people receiving
the injections—the quantities were too
small—but the studies might have led
to the development of new therapies for
future patients.
Results of the Injection
Experiments
By 1950, five years after the start of the
study, Langham and Bassett, as well as
Payne Harris and Robert Carter from
Los Alamos, wrote a classified report
(LA-1151) that summarized much of
what had been learned from the eleven
Rochester patients, the Oak Ridge pa-
tient, the three Chicago patients, and
the first California patient. They con-
cluded that about two-thirds (66 per
cent) of the plutonium injected into the
bloodstream was deposited in the skele-
ton and more than a fifth (23 per cent)
was deposited in the liver. Thus, “the
skeletal system and liver are the tissues
of major interest when considering the
plutonium tolerance, as these two or-
gans alone account for 90% or more of
the total plutonium in the entire body.”
The level of plutonium in the blood
was high at first (35.7 per cent of the
injected amount after 4 hours and 15.7
per cent after 1 day) but fell rapidly
(1.2 per cent after 10 days and 0.3 per
cent after 30 days), which ruled out the
use of blood tests “as a means of diag-
nosing the degree of exposure of per-
sonnel.”
The Los Alamos report used the accu-
mulated data obtained from the fifteen
patients to determine excretion rate
equations, which appeared (for both
urinary and fecal excretion) to be most
easily described by “a logarithmic func-
tion:
Y
5
a X
2
b
,
The Human Plutonium Injection Experiments
210
Los Alamos Science Number 23 1995
continued from page 207