True?
http://www.pdhealth.mil/downloads/Chem-Rad-DU.pdf
>...Once absorbed in the blood stream, uranium circulates as the
uranyl ion (U0
22
+), forming uranium-carbonate and uranium-
albumin complexes.
24
Approximately 90% of a single uranium
exposure is renally eliminated in the first 24 hours.
14
The re-
maining 10% is rapidly redistributed to the bones and other
organs. Sixty-six percent of the total uranium body burden
resides in the skeleton, where the uranyl ion codeposits with
calcium.
14.20
The average human body contains approximately
100 µg of uranium.
14
The kidney, liver, and muscle are the
major extraskeletal sites of uranium deposition with the kidney
potentially acting as a second site of long-term storage.
24 25
Nor-
mal urinary uranium excretion levels range from 0.04 to 0.5
µg/L urine.'
4
Radiobiological Characteristics of DU
The radiological effects of DU are considered a "negligeable
hazard."
14
Because of the very long half-lives of the
individual
radioisotopes
(234
U
,
245,000 years;
235
U,
704
X
10
6
years; and
238
U,
4,470 X 10
6
years), the specific activity of uranium is
low.
20.26
The predominant radioisotope,
238
U, also has the long-
est half-life and therefore the lowest specific activity. Placed in
perspective, radon has a specific activity 10,000 times greater
than naturally occurring uranium. By its very nature, DU con-
tains only 50% to 60% of the radioactivity of naturally occurring
uranium.
19.20.26
DU is approximately 3 million times less radio-
active than Ra-226 found in luminous clocks and watches and
10 million times less radioactive than Am-241 found in fire
detectors.''
Uranium emits α, β, and γ ionizing radiation.
27.28
Although α
particles are the primary radiation hazard, these particles are
unable to penetrate the superficial layers of dead skin and so do
not pose any external radiation risk.
9
These α particles do pose
a potential hazard upon inhalation, ingestion, or contamination
of open wounds. β and γ radiation, although present in much
lower activities, do represent a potential external radiation haz-
ard. Calculated potential whole body radiation doses in tank
crew members have demonstrated levels of 0.00001 to 0.00013
rem/h (0.001-0.013 Sv/h) above ambient background.
23
The
maximum possible annual whole body radiation dose in a sce-
nario involving continuous exposure would be 2.6 rem (260 Sv),
which is one-half the current annual occupational exposure
limit. Direct contact with DU ammunition produces a skin dose
rate of 0.2 rem/h, predominantly through β particle emis-
sions.
23
Direct skin contact for 250 hours per year would be
required to exceed current occupational skin dose limits
Michael Pugliese