International Depleted Uranium Study Team
Environmental Audit Committee
Clerk of the Committee
7 Millbank
Dear Sirs/Madams:
I applaud your committee’s efforts in exploring the
environmental remediation requirements that must, or should, be met in order
that reconstruction efforts in
With this in mind, I strongly urge the committee to include
within the parameters of its inquiry the effects that the expenditure of large
amounts of depleted uranium munitions have had and will continue to have on the
environment in
However, the evidence we have today on DU strongly speaks to
the contrary. This evidence includes the DU warnings that the MoD itself is
currently giving to its troops in
The evidence also includes the rising incidence of childhood
cancer, leukemia and birth deformities observed in southern
These factors, taken together, add credence to the
possibility that DU poses a grave threat to the environment and to the health
of those who are forced to live day-in and day-out in its presence. The UNEP
report of
In the pages that follow, I present a brief introduction to
DU and its use by the UK and USA as munitions in Iraq and an explanation of the
physical/physiological mechanisms by which DU-oxide dust, produced when DU
munitions are used, poses such a grave
threat to health, including how DU contamination from expended munitions and
exploded bombs is very different from background uranium in the environment. If
one is to hope that the citizens of
Should the committee determine that my presence for oral testimony would be helpful in their deliberations, I will be happy to testify in person if travel expenses can be arranged.
Sincerely,
Dr. Dan Bishop, Ph.D.
President, IDUST Board
Background
Information
Depleted uranium (DU) is a radioactive heavy metal. As radioactive substances go, depleted uranium is one of the least radioactive substances known. Armed with this fact, the Department of Defense in the United States and the Ministry of Defense in Great Britain have consistently maintained that exposure to DU is, if not totally harmless, at least no more harmful than “background radiation”. Their arguments might be persuasive were it not for the fact that the particular type of DU left behind on battlefields where DU munitions have been used is substantively different in several ways from naturally occurring uranium. It is these very differences that make DU such a grave threat both to humans exposed to DU on a daily basis and to the environment in which they live.
At least 320 tons of DU were
expended in the
During the invasion of
The half-life of DU is 4.5 billion years. This means that,
when the earth is finally destroyed by the sun’s corona expanding into earth’s
orbit some 4.5 billion years from now, only half of the DU spread into
Why DU-oxide dust is
more hazardous than natural uranium
When a DU round or bomb strikes a hard target, most of its kinetic energy is converted to heat — sufficient heat to ignite the DU, which is pyrophoric, like magnesium, for example. The DU burns at nearly 5000 degrees Fahrenheit. It is this fact, in addition to DU’s high density (19.05 g/cm3, making it one of the densest metals known), that makes it such an effective penetrator, in that DU missiles, once ignited, actually melt their way through armor, concrete and rock and thus gain entry into the tank or bunker where the resulting conflagration destroys the target. In the process, as reported in an official US Army AEPI technical report from 1995, from 40% to 70% of the DU is converted to extremely fine dust particles of ceramic uranium oxide (primarily dioxide, though other formulations also occur). Over 60% of these particles are smaller than 5 microns in diameter, about the same size as the cigarette ash particles in cigarette smoke and quite efficiently respirable. In addition, the extreme heat creates an environment wherein the uranium oxide dust that is formed assumes a unique crystalline structure referred to as a ceramic.
It is this difference in particle size and the ceramic nature of the dust’s crystalline structure that make the presence of DU dust in the environment such an extreme hazard, and which differentiates its properties from that of the natural uranium dust that is ubiquitous and to which we all are exposed every day.
In the first place, natural uranium dust in the environment seldom reaches micron dimensions, as the conditions needed for this are simply not commonly available in nature. When inhaled, these larger particles cannot access the deepest air pockets in the lungs and are moved out of the air passages through exhalation and the action of millions of cilia in the trachea. They are then deposited into the esophagus and swallowed. Once in the digestive system, 67% of the uranium ingested is excreted within 24 hours. Of that which does make it into the circulatory system from the digestive tract, 90% will be excreted through the kidneys within a few days. Only a small portion will take up permanent residence in bone tissue, gonads, liver and the like. Solubilized DU can also cross the blood-brain barrier, leading to neurological disorders, and cross through the placenta to infect a developing fetus.
Particles smaller than 10 microns can access the innermost recesses of lung tissue where they become permanently lodged. Furthermore, if the substance is relatively insoluble, such as the ceramic DU-oxide dust produced from burning DU, it will remain in place for decades, dissolving very slowly into the bloodstream and lymphatic fluids through the course of time. Studies have identified DU in the urine of Gulf War veterans nine years after that conflict, testifying to the permanence of ceramic DU-oxide in the lungs.
Based on dissolution and excretion rate data, it is somewhat possible to extrapolate backwards and approximate the amount of DU initially inhaled by these veterans. For the handful of veterans studied, this amount averaged 0.34 milligrams. Knowing the specific activity (radiation rate) for DU allows one to determine that the total radiation (alpha, beta and gamma) occurring from DU and its radioactive decay products within their bodies comes to about 26 radiation events every second, or 800 million events each year. (See Addendum A (#1-4) for supporting calculations.)
This is where the second issue related to particle size comes into play – namely surface area. Any chemist or technician working with catalysis knows that the effectiveness of a catalyst is proportional to its surface area. The same factors apply to the “effectiveness” of a particle emitting ionizing radiation. 0.34 mg of DU dispersed as 4.3 million 2.5 micron diameter particles has nearly 50% more surface area than a single 0.34 mg sphere of DU. From such small particles, all of the gamma radiation emitted and most of the beta radiation emitted will escape the particle and affect the surrounding tissues. For the bulkier and less penetrating alpha radiation, most will be absorbed within the particle itself. Only alpha radiation from those atoms on or near the surface of the particle has any chance of escaping outside the particle and causing damage. For this reason, it is apparent that the smaller particles with larger surface area are significantly more hazardous than the larger particles in natural uranium dust.
The calculations in Addendum A (#5-8) account for this factor and assume that only the alpha radiation emitted from atoms within the ten layers closest to the particle’s surface have any chance of escaping from the particle. They also include a factor of 30% to account for the fact that only a portion of the alpha radiation emitted by an atom will be directed outward so that escape is possible; the remaining 70% will be directed inward and blocked by other molecules within the particle. The calculations further assume that 80% of all beta radiation and 100% of all gamma radiation successfully exits the particle and affects surrounding tissue. Taking both factors into account, the calculations show that one can expect approximately 1100 damaging radiation events every minute, 1.6 million damaging events per day, or 578 million damaging radiation events per year from 0.34 mg of DU dispersed throughout the lungs in the form of 4.3 million 2.5 micron diameter particles.
Effects on cells and
tissue exposed to DU
Addendum B presents a sampling of nine recent scientific research reports that
pertain to the effects of DU exposure on human health and on cell tissue. Of
significance is that several reports in the last three years have come from the
US Army’s own Applied Cellular Radiobiology Department, Armed Forces
Radiobiology Research Institute labs in
There is special significance to the word “ionizing” when describing radiation in the form of alpha and beta particles and gamma rays (photons). Alpha and beta particles are charged particles that are emitted from a decaying DU atom at speeds approaching 10% the speed of light. Because they are charged (“ionized”) they can fracture molecules without even colliding with them. The effect is similar to that observed when a magnet is brought near a pile of iron filings. The ionic charge on the radiation particle can displace bonding electrons in nearby molecules as it whizzes by, creating in its wake free radicals, DNA cleavage, etc. Because of this, one beta particle, for example, may adversely affect dozens of cells before it finally actually strikes a molecule and comes to rest. Alpha particles, being larger, don’t travel nearly so far, but they have twice the ionic charge as beta particles and are thousands of times as massive. So when an alpha particle actually collides with a molecule, the results are cataclysmic and often result in cell death and the release of dozens of free radicals into neighboring cells.
Gamma rays are not charged particles like alpha and beta particles, but are photons of electromagnetic radiation. A gamma photon must actually strike a molecule to cause damage. When a gamma photon strikes a molecule, its energy is absorbed by the electrons in the molecule, placing the molecule in an “excited state”. The molecule releases this newly obtained energy by immediately shooting a bonding electron (identical to a beta particle) into the surroundings along with another gamma ray of less energy than that of the original gamma ray. The released electron acts like any other beta particle, but it has originated some distance away from the original irradiating source of DU. The new gamma ray proceeds on its own new course until it too strikes a distant molecule and the process repeats itself. This goes on until all of the energy originally present in the first gamma ray has been used up. Thus one gamma emission from a radioactive atom can result in the production of many beta particles in a zig-zag track throughout the tissue, and each beta particle leaves its own wake of destroyed molecules.
Chemical Toxicity of
DU
In addition to its radioactive nature, DU is also a heavy metal and is chemically toxic, exhibiting a toxicity similar to that of chromium and lead. In the United States, a great deal of attention has been made over old paint in rental apartments that may contain lead-based pigment – tenants’ children might eat the stuff as it peals off the walls and window sills. Tetraethyl lead has been phased out as an additive to automobile gasoline. Similar consideration, based on DU’s very well documented chemical toxicity alone, should be given to Iraqi children’s exposure who have actually been seen PLAYING with spent DU munitions and shell fragments. Or to the exposure of teenagers who have been seen playing in and around tanks destroyed with DU penetrators and which are literally coated with DU-oxide dust.
Observers in
Environmental
distribution of DU-oxide dust
A common misconception, and one often expressed by military spokespersons, is that since DU-oxide particles are so dense, they cannot travel far from where they are formed, namely the burning tanks or bunkers that were targeted. If the particles were of normal size, there might be merit to that argument. However, micron size particles present an entirely different picture.
Imagine trying to float a tank across the
Now imagine a 2.5 micron diameter particle of DU-oxide dust
as it falls to the ground. It is radioactive, so that with each charged alpha
and beta particle emitted, the dust particle assumes an additional
electrostatic charge. Thus the DU-oxide particle is endowed with a natural
“static cling”. On contact with the earth it becomes electrostatically attached
to a (relatively) huge particle of sand. The DU-oxide particle is so small that
its weight doesn’t affect the overall weight of the sand particle. Sand storms
are a common phenomenon in desert regions and occur frequently in
To lend further credence to distribution by natural mechanisms, spokespersons for DU munitions in the military often refer to the background radiation from natural uranium and how ubiquitous natural uranium is. Natural uranium is about as dense as DU. So one might ask, if DU dust is not supposed to travel great distances, how do you explain the fact that the entire earth is covered with a small amount of natural uranium, often quite far removed from uranium ore deposits where it originated?
There may now be some evidence of DU contamination of
southern
Recommendations
Cleansing the Iraqi environment of depleted uranium will be no easy task, particularly since DU-oxide dust from the 1991 Gulf War has had 13 years to spread into the environment. However, the project must be undertaken as an integral part of the reconstruction efforts for the Iraqi society.
To that end, the following specific problems must be addressed:
Finally, it is imperative that these studies and assessments be conducted by individuals, groups and organizations that DO NOT have a vested interest in “proving” that DU contamination is benign. This includes any person or organization associated with the nuclear power industries (e.g. WHO, which is required to vet all reports through the IAEA, the IAEA, the NRC, possibly even UNEP), with the DoD or MoD, with military contractors and suppliers, and researchers whose funding relies on any of these sources. It is vital for the Iraqi people, and for all of us, that the forthcoming information in these studies be as unbiased and untainted as is humanly possible.
Respectfully Submitted to the Environmental Audit Committee,
Parliament,
by
Dr. Dan Bishop, Ph.D. (Chemistry)
President, International Depleted Uranium Study Team (IDUST)
Addendum A
DU– Micron Sized Particulate Data Sheet
by Dr. Dan Bishop, Ph.D. (Chemistry)
Summary of Calculations:
Particles smaller than 10 microns, when inhaled, become permanently lodged in the deepest recesses of the lungs. Taking 2.5 microns as the average size of a respirable DU-oxide particle, simple calculations reveal the following:
A 2.5 micron diameter particle of UO2 weighs 9.0
x 10-11 gram, contains 7.9 x 10-11 gram of DU, has a
volume of 8.2 x 10-18 m3
and surface area of 2.0 x 10-11 m2 and contains
2.0 x 1011 molecules, with each molecule occupying roughly 2 x 10-10
m3 . There are roughly 1.4 x 108 molecules on the
particle’s surface, accounting for 0.07% of the total number of molecules
present.
Studies of some Gulf War veterans have indicated an initial 1991 body burden of as much as 0.34 grams of DU that became permanently absorbed in lung tissue. This amounts to 4.3 million particles having a 2.5 micron diameter. The ALPHA activity for 0.34 grams of DU is 5.2 Bq (5.2 ALPHA disintegrations per second, 160 million alpha disintegrations per year), making total activity (alpha, beta and gamma) equal to 26 disintegrations per second, or 800 million radiation events per year.
For large particles (e.g. shrapnel), most radiation events within the particle are absorbed within the particle. This is particularly true of alpha radiation, the bulkiest and least energetic of the three types of radiation. Alpha radiation emitted by atoms on or near the surface that is directed outward will be the only alpha radiation to affect surrounding tissue. Assuming atoms more than ten layers deep will be unable to radiate beyond the particle’s surface, and that only 30% of the alpha radiation from those near the surface, on average, will be oriented outward and able to escape, one can calculate that roughly 0.2% of the total alpha radiation from this particle can reach surrounding tissue.
From such tiny particles, the much smaller and more penetrating beta emissions may be expected to have as much as an 80% success rate for escaping the particle and penetrating surrounding tissue, while gamma radiation, being non-particulate in nature, will have a 100% success rate. Taken together, these assumptions result in a finding that one can expect that the total number of radiation events to penetrate living tissue from a 0.34 mg body burden of depleted uranium will be approximately 1100 events per minute, 1.6 million events per day, or 578 million radiation events per year.
Because alpha and beta radiation are IONIZING radiation and gamma exposure leads to secondary IONIZING radiation (the Compton effect), each radiation event carries with it the possibility of MULTIPLE occurrences of molecule destruction and free-radical generation along the entire wake of its trajectory. Each alpha radiation event always results in complete destruction of at least one cell with consequent generation of dozens of free-radicals. So either through direct bombardment or through secondary free-radical generation, incidents of cell damage, chromosome cleavage and DNA alteration (all observed in laboratory tests), and their subsequent consequences (cancers, lymphomas, leukemia, sterility and birth defects) , simple logic tells us that exposure to DU radiation cannot help but be considered harmful.
Calculations
1. Mass, volume and surface area of a 2.5 micron particle of UO2:
(Ref: CRC
Handbook of Chemistry and Physics, 51st Edition. Pub. by The Chemical Rubber Company,
a. Density of UO2: d = 11 g/cm3 = 11 x 106 g/m3
b. 2.5 micron diameter particle has radius: r = 1.25 x 10-6 meter
c. Volume of a 2.5 micron diameter sphere:
V = 4/3 π r3 = 4/3 π (1.25
x 10-6 meter)3 = 8.2 x 10-18 m3
d. Surface area of a 2.5 micron diameter sphere:
A = 4 π r2 = 4 π (1.25 x 10-6 meter)2 = 2.0 x 10-11 m2
.
e. mass of a 2.5 micron diameter UO2 particle:
m = (d)(V) = (11 x 106 g/m3)( 8.2 x 10-18 m3) = 9.0 x 10-11 gram
f. mass of DU in this particle: (238/270)( 9.0 x 10-24 gram) = 7.9 x 10-11 gram
2. By analyzing the urine of several 1991 Gulf War veterans’ urine nine years after their exposure and calculating what their initial exposure must have been to result in the observed DU concentrations in their urine, it is possible to estimate that these veterans had inhaled around 0.34 mg, or 3.4 x 10-4 gram, of DU.
(Ref: Estimate
of the time zero lung burden of depleted uranium in Persian Gulf War veterans
by the 24-hour urinary excretion and exponential decay analysis. A.
Durakovic, et al., Military Medicine, Vol. 168(8), Aug. 2003 (pp. 168
ff.).
Number of 2.5 micron particles permanently inhaled (in 0.34 grams):
N = 3.4 x 10-4 gram / 7.9 x 10-11 gram = 4.3 x 106 = 4.3 million particles
3. Specific alpha radioactivity of 2.5 micron particle per second and per year:
a. Specific ALPHA activity of 1mg of DU is 14.8
Bq, or 14.8 disintegrations per second.
b. A 2.5 micron particle weighing 7.9 x 10-11 gram thus gives off:
(14.8 alpha/sec) (7.9 x 10-11 gram) / (1 x 10-3 gram) =
1.20 x 10-6 ALPHA disintegrations per second.
c. There are 60 x 60 x 24 x 365 = 3.15 x 107 seconds per year, so:
(1.20 x 10-6 alpha/sec)(3.15 x 107 sec/yr) = 38 ALPHA disintegrations per year
for EACH 2.5 micron diameter particle.
d. For 4.3 million particles, the estimated number inhaled, the results are:
(4.3 x 106)( 1.20 x 10-6 alpha/sec) = 5.2 ALPHA disintegrations per second.
(4.3 x 106) (38 alpha/yr) = 160 x 106 = 160 million ALPHA disintegrations per year.
4. Since the decay products in DU emit TWO beta disintegrations and TWO gamma rays for each alpha disintegration of DU, 0.34 mg of DU results in:
(5.2 alpha ) + 2(5.2 beta) + 2(5.2 gamma) = 26 radiation events per second.
(160 x 106 alpha ) + 2(160 x 106 beta) + 2(160 x 106 gamma) = 800 x 106 =
800 million radiation events per year.
5. Atom packing density - spheres within a larger sphere:
a. Given a 2.5 micron diameter sphere (r = 1.25 x 10-6 m) consisting of 9.0 x 10-11 gram of UO2, the number of molecules in this particle is calculated from Avogadro’s number, which is 6.023 x 1023 molecules/mole, and 1 mole of UO2 , which equals 270 grams. Thus:
(9.0 x 10-11 gram )(6.023 x 1023 molecules/mole) / (270 g/mole) =
2.0 x 1011 molecules of UO2 in each 2.5 micron particle.
b. The tightest packing of spheres (molecules) within a larger sphere (the 2.5 micron particle) has been mathematically found to be 78%; the remaining 22% is empty space. The volume of each molecule can be found by dividing 78% of the volume of the 2.5 micron diameter sphere by the number of molecules in the particle:
0.78 (8.2 x 10-18 m3 ) / (2.0 x 1011 molecules) = 3.2 x 10-29 m
c. The radius of each molecule can be found from its volume: r = cube root of 3V/4π
r = cube root ( 3 (3.2 x 10-29 m)/( 4π) = 2 x 10-10 m
d. The cross-sectional area of each molecule is simply the area of a circle: A = π r2.
A = π(2 x 10-10 m)2 = 1.3 x 10-19 m2 .
e. The tightest packing of circles within a circle is 91% of the larger circle’s area. Assuming this would roughly represent the packing of circles over the surface of a sphere, one can estimate the number of molecules on the surface of a 2.5 micron diameter particle by dividing 91% of the particle’s surface area by the cross-sectional area of each molecule:
0.91 (2.0 x 10-11 m2 ) / (1.3 x 10-19 m2) = 1.4 x 108 surface molecules.
Allowing for the top ten layers to have molecules located where alpha radiation (the least energetic, and also the bulkiest) could escape the particle, we are dealing with 1.4 x 109 molecules, which represents:
(1.4 x 109 molecules) / (2.0 x 1011 total molecules) = 0.7% of total
f. Now if only 30% of the alpha radiation from these 0.7% of total molecules is directed toward the surface of the particle and can escape, 30% of 0.7% = 0.2% for alpha radiation.
g. On the other hand, from such tiny particles it is reasonable to assume that 80% of the beta radiation and 100% of the gamma radiation could escape and effect surrounding tissue. Thus the contribution from each type of radiation must be taken into account separately.
g. With these assumptions, we can adjust the total number of radiation events calculated in step 4 to determine the number of radiation events that actually reach surrounding tissue and cause damage:
For Alpha Radiation:
0.2% (5.2 events/sec) (60 sec/min) = 0.6 alpha radiation event per minute
For Beta Radiation:
80% (10.4 events/sec)(60 sec/min) = 499 beta radiation events per minute
For Gamm Radiation:
100% (10.4 events/sec)(60 sec/min) =
624 gamma radiation events per minute
Thus
the total number of damaging radiation events to penetrate living tissue from a
0.34 mg body burden of depleted uranium will be approximately 1100 events per
minute, 1.6 million events per day, or 578 million radiation events per year.
Addendum B
Sampling of Recent Scientific Literature
Citations on DU Studies
I.
Cellular and Molecular Response to Uranium
and Depleted Uranium Exposure
Uranium compounds have been shown to create DNA strand breaks1, a phenomenon known to be a precursor to cellular genetic mutations that lead to cancer and genetically caused birth defects. Studies of lymphocytes in Gulf and Balkan war veterans’ blood showed chromosome aberrations and sister chromatid exchanges, indicative of exposure to ionizing radiation2. Radiation induced genomic instability from DU exposure was demonstrated by observing delayed reproductive death and micronuclei formation in human bone cells3. Both soluble and insoluble DU compounds have been shown capable of transforming cells to the tumorigenic phenotype characterized by morphological, biological and oncogenic changes consistent with tumor cell behavior.4 Radiation specific damage has been observed to human cells directly exposed to DU.5
1.
Uranyl acetate causes DNA single strand breaks
in vitro in the presence of ascorbate (Vitamin C). M. Yazzie, et al., Chemical Research in
Toxicology, 16(4), April 2003 (pp. 524-530). Department of
Chemistry,
Uranium is a radioactive heavy metal with
isotopes that decay on the geological time scale. People are exposed to uranium
through uranium mining, processing, the resulting mine tailings, and the use of
depleted uranium in the military. Acute exposures to uranium are chemically
toxic to the kidney; however, little is known about chronic exposures, for
example, if there is a direct chemical genotoxicity of uranium. The hypothesis
that is being tested in the current work is that hexavalent uranium, as uranyl
ion, may have a chemical genotoxicity similar to that of hexavelent chromium.
In the current study, reactions of uranyl acetate (UA) and ascorbate (vitamin
C) were observed to produce plasmid relaxation in pBluescript DNA. DNA strand
breaks increased with increasing concentrations of a 1:1 reaction of UA and
ascorbate but were not affected by increasing the ration of ascorbate. Plasmid
relaxation was inhibited by coincubation of reactions with catalase but not by
coincubation with the radical scavengers mannitol, sodium azide, or 5,5-dimethyl-1-pyrroline-N-oxide. Reactions of UA and
ascorbate monitored by (1)H NMR spectroscopy showed
formation of a uranyl ascorbate complex, with no evidence of a dehyroascorbate
product. A previous study inferred that hydroxyl radical formation was responsible
for oxidative DNA damage in the presence of reactions of uranyl ion, hydrogen
peroxide, and ascorbate [Miller et al. (2002) J. Bioinorg. Chem. 91, 246-252].
Current results, in the absence of added hydrogen peroxide, were not completely
consistent with the interpretation that strand breaks were produced by a Fenton
type generation of reactive oxygen species. Data were also consistent with the
interpretation that a uranyl ascorbate complex was catalyzing hydrolysis of the
DNA-phosphate backbone, in a manner similar to that known for the lanthanides.
These data suggest that uranium may be directly genotoxic and may, like
chromium, react with DNA by more than one pathway.
2.
Chromosome aberration analysis in peripheral
lymphocytes of Gulf War and Balkans War veterans. H. Schroder, et al., Radiation
Prot Dosimetry Vol. 103(3), 2003 (pp. 211-219). Center of Environmental
Research and Technology,
Chromosome aberrations and sister chromatid
exchanges (SCEs) were determined in standard peripheral lymphocyte metaphase
preparations of 13 British Gulf War veterans, two veterans of the recent war in
the Balkans and one veteran of both wars. All 16 volunteers suspect exposures
to depleted uranium (DU) while deployed at the two different theaters of war in
1990 and later on. The
3.
Genomic instability in human osteoblast cells
after exposure to depleted uranium: delayed lethality and micronuclei formation.
A. Miller, et al., Journal of Environmental Radioactivity, 64(2-3), 2003
(pp. 247-259). Applied Cellular Radiobiology Department Armed Forces
Radiobiology Research Institute,
It is known that radiation can induce a
transmissible persistent destabilization of the genome. We have established an
in vitro cellular model using HOS cells to investigate whether genomic
instability plays a role in depeleted uranium (DU)-induced effects. Transmissible
genomic instability, manifested in the progeny of cells exposed to ionizing
radiation, has been characterized by de novo chromosomal aberrations, gene
mutations, and an enhanced death rate. Cell lethality and micronuclei formation
were measured at various times after exposure to DU, Ni, or gamma radiation.
Following a prompt, concentration dependent acute response for both endpoints,
there was de novo genomic instability in progeny cells. Delayed reproductive
death was observed for many generations (36 days, 30 population doublings)
following exposure to DU, Ni, or gamma radiation. While DU stimulated delayed production
of micronuclei up to 36 days after exposure, levels in cells exposed to
gamma-radiation or Ni returned to normal after 12 days. There was also a
persistent increase in micronuclei in all clones isolated from cells that had
been exposed to nontoxic concentrations of DU. While clones isolated from
gamma-irradiated cells (at doses equitoxic to metal exposure) generally
demonstrated an increase in micronuclei, most clonal progeny of Ni-exposed
cells did not. These studies demonstrate that DU exposure in vitro results in
genomic instability manifested as delayed reproductive death and micronuclei
formation.
4.
Potential
late health effects of depleted uranium and tungsten used in armor-piercing
munitions: comparison of neoplastic transformation and genotoxicity with the
known carcinogen nickel. A. Miller, et al., Military Medicine Vol. 167
(2 suppl), Feb. 2002 (pp. 120-122). Applied Cellular Radiobiology
Department Armed Forces Radiobiology Research Institute,
Limited data exist to permit an accurate
assessment of risks for carcinogenesis and mutagenesis from embedded fragments
or inhaled particulates of depleted uranium (DU). Ongoing studies have been
designed to provide information about the carcinogenic potential of DU using
in-vitro and in-vivo assessments of morphological transformation as well as
cytogenetic, mutagenic, and oncogenic effects. For comparison, we also examined
tungsten alloys used in military projectiles and the known carcinogen nickel.
Quantitative and qualitative in-vitro transformation studies were done to
assess the carcinogenic potential of radiation and chemical hazards. Using a
human cell osteosarcoma cell model, we demonstrated that soluble and insoluble
DU compounds can transform cells to the tumorigenic phenotype, as characterized
by morphological, biochemical and oncogenic changes consistent with tumor cell
behavior. Tungsten alloys and nickel were also shown to be neoplastic
transforming agents, although at a frequency less than that of DU. Sister chromatid exchange, micronuclei, and alkaline filter elution
assays showed DU and tungsten alloys were genotoxic. Exposure to a non-toxic,
nontransforming dose of DU induced a small but statistically significant
increase in the number of dicentrics formed in cells. These results suggest
that long term exposure to DU or tungsten alloys could be critical to the
development of neoplastic disease in humans and that additional studies are
needed.
5.
Observation
of radiation-specific damage in human cells exposed to depleted uranium:
dicentric frequency and neoplastic transformation as endpoints. A Miller,
et al., Radiat Prot Dosimetry Vol. 99(1-4), 2002 (pp. 275-278). Applied
Cellular Radiobiology Department Armed Forces Radiobiology Research Institute,
Depleted uranium (DU) is a dense heavy metal
used primarily in military applications. Published data from our laboratory
have demonstrated that DU exposure in-vitro to immortalsed human osteoblast
cells (HOS) is both neoplastically transforming and genotoxic. DU possesses
both a radiological (alpha particle) and chemical (metal) component. Since DU
has a low specific activity in comparison to natural uranium, it is not
considered to be a significant radiolgical hazard. The potential contribution
of radiation to DU-induced biological effects is unknown and the involvement of
radiation in DU-induced biological effects could have significant implications
for current risk estimates for internalised DU exposure. Two approaches were
used to address this question. The frequency of dicentrics was measured in HOS
cells following DU exposure in vitro. Data demonstrated that DU exposure (50
micorM, 24h) induced a significant elevation in dicentric frequency in vitro in
contrast to incubation with heavy metals, nickel and tungsten, which did not
increase dicentric frequency above background levels. Using the same
concentration (50 microM) of three uranyl nitrate compounds that have different
uranium isotopic concentrations and therefore different specific activities,
the effect on neoplastic transformation in-vitro was examined. HOS cells were
exposed to one of three-uranyl nitrate compounds (238U-uranyl nitrate, specific
activity 0.33 microCi.g-1; DU uranyl nitrate, specific activity 0.44
microCi.g-1; and 235U-uranyl nitrate, specific activity 2.2 microCi.g-1)
delivered at a concentration of 50 microM for 24 h. Results showed, at equal
uranium concentration, there was a specific activity dependent increase in
neoplastic transformation frequency. Taken together, these data suggest that
radiation can play a role in DU-induced biological effects in vitro.”
II.
Organ
and Organism Response to Uranium and
Depleted Uranium Exposure
(Including Studies on Embedded DU
Fragments)
Analysis of urinary DU excretion up to nine years following inhalation exposure and known biological half-life figures for ceramic DU oxide in the lungs can be used to estimate the extent of initial pulmonary exposure to DU.1 Results showed exposed veterans had inhaled 0.34 mg of DU, over 2200 times the time-zero estimated DU lung burden of non-exposed veterans. Another paper showed that radiation and chemical damage to kidneys, lungs and other internal organs was observed in a study of over 600 humans exposed to DU.2
A study has compared the biokinetics of DU migration in the body from embedded fragments with the more common laboratory migration studies which use injection of soluble uranyl nitrate and found the results to be comparable with respect to long-term accumulation in kidney, bone and liver tissues.3 Furthermore, 24-hour urine samples from 27 Gulf War Veterans ten years after the war were tested for DU and 14 of the veterans’ samples showed clearly positive results.4
1. Estimate of the time zero lung burden of
depleted uranium in Persian Gulf War veterans by the 24-hour urinary excretion
and exponential decay analysis. A. Durakovic, et al., Military Medicine,
Vol. 168(8), Aug. 2003 (pp. 168 ff.).
The aim of this study was to estimate the amount
of depleted uranium (DU) in the respiratory system of Allied Forces Gulf War
Veterans. Mass spectrometry (thermal ionization mass spectrometry) analysis of
24-hour urinary excretion of DU isotopes in five positive (238U/235U > 191.00)
and six negative (238U/235U > 138.25) veterans was utilized in the
mathematical estimation of the pulmonary burden at the time of exposure. A minimum value for
the biological half-life of ceramic DU oxide in the lungs was derived from the
Battelle report of the minimum dissolution half-time in simulated interstitial
lung fluid corresponding to 3.85 years. The average DU concentration was 3.27 x
10(-5) mg per 24 hours in DU-positive veterans and 1.46 x 10(-8) mg in
DU-negative veterans. The estimated lung burden was 0.34 mg in the DU-positive
and 0.00015 mg in the DU-negative veterans. Our results provide evidence that
the pulmonary concentration of DU at time zero can be quantitated as late as 9
years after inhalational exposure.
2. Depleted
Uranium: radiation and ecological safety aspects. I.B. Ushakov, et al.. Voenno-Meditsinskii
Zhurnal, 324(4), 2003 (pp. 56-8) (Russian). [Ushakov-2003/4-VMZ-324(4),55]
The authors have analyzed the ecological,
sanitary-and-hygenic and medicobiologic aspects of using the impoverished
uranium in armaments and military equipment. The influence of impoverished
uranium on human body (600 cases) was studied using medicobiologic
investigation. It was shown that the particles of aerosol of mixed uranium
oxide cause the radiation and chemical damage of kidneys, lungs and other
internals. Uranium’s alpha radiation is very effective in induction of biologic
effects during internal radiation. Taking into account that bone tissue is the
critical organ for uranium isotopes the medullar tissue is exposed to
alpha-radiation. In the armed conflicts of the last decade, wide use of
armour-piercing means with elements consisted of impoverished uranium has led
to the appearance of new technogenic risk factor for the environment and the
man.
3. The
biokinetics of uranium migrating from embedded DU fragments. R.W. Leggett,
et al., Journal of Environmental Radioactivity, Vol. 64(2-3), 2003 (pp.
205-225). Life Sciences Division of
Military uses of depleted uranium (DU) munitions
have resulted in casualties with embedded DU fragments. Assessment of
radiological or chemical health risks from these fragments requires a model
relating urinary U to the rate of migration of U from the fragments, and its
accumulation in systemic tissues. A detailed biokinetic model for U has been
published by the International Commission on Radiological Protection (ICRP),
but its applicability to U migrating from embedded DU fragments is uncertain. Recently,
Pellmar and colleagues (1999) conducted a study at the Armed Forces
Radiobiology Research Institute (AFRRI) on the redistribution and toxicology of
U in rats with implanted DU pellets, simulating embedded fragments. This paper
compares the biokinetic data from that study with the behavior of commonly
studied forms of U in rats (e.g., intravenously injected U nitrate). The
comparisons indicate that the biokinetics of U migrating from embedded DU is
similar to that of commonly studied forms of U with regard to long-term
accumulation in kidneys, bone and liver. The results provide limited support
for the application of the ICRP’s model to persons with embedded DU fragments.
Additional information is needed with regard to the short term behavior of migrating
U and its accumulation in lymph nodes, brain, testicles and other infrequently
studied U repositories.
4. The
quantitative analysis of depleted uranium in British, Canadian and
The purpose of this work was to determine the
concentration and ratio of uranium isotopes in allied forces Gulf War Veterans.
The 27 patients had their 24-hour urine samples analyzed for 234U, 235U, 236U
and 238U by mass spectrometry. The urine samples were evaporated and separated
into isotopic dilution and concentration fraction by the chromatographic
technique. The isotopic composition was measured by a thermal ionization mass
spectrometer using a secondary electron multiplier detector and ion-counting
system. The uranium blank control and SRM960 U isotopic standard were analyzed
by the same procedure. Statistical analysis was done by an unpaired t test. The
results confirm the presence of depleted uranium (DU) in 14 of 27 samples, with
the 238U:235U ratio > 207.15. This is significantly different from
natural uranium (p<0.008) as well as from the DU shrapnel analysis, with
22.22% average value of DU fraction, and warrants further investigation.
Addendum C
Gulf War Syndrome Symptoms Compared to
Radiation Illness
Table I
52,835 Gulf War Veterans in a
Fatigue 20.5%
Skin Rash 18.4%
Headache 18.0%
Muscle & Joint Pain 16.8%
Memory Loss 14.0%
Shortness of Breath 7.9%
Sleep Disturbance 5.9%
Diarrhea & other GI symptoms 4.6%
Other skin/integumentary tissue 3.6%
Chest Pain 3.5%
Table II
20,000 Gulf War Veterans in the DoD Comprehensive Clinical
Evaluation Program (CCEP) through
Joint Pain 49%
Fatigue 47%
Headache 39%
Memory Loss 34%
Sleep Disturbance 32%
Skin Rash 31%
Difficulty Concentrating 27%
Depression 23%
Muscle Pain 21%
Diarrhea 18%
Shortness of Breath 18%
Abdominal/Gastrointestinal Pain 17%
Hair Loss 12%
Table III
Chronic complaints of victims of secondary radiation exposure to
Constant Fatigue & Lack of Stamina
Skin Rash
Headache
Stiff Shoulders, Numbed hands & feet
Poor Memory & Dizziness
Sleeplessness
Nausea
Severe Palpitations
Loss of Weight
Rush of Blood to Head
Table IV
284
Muscle & Joint Pain 35%
Tiredness 55%
Short-term Memory Loss 22%
Sleep Disturbance 24%
Skin Problems 16%
Irritability 29%
Tingling in Limbs 11%
Breathlessness 21%
Tables I, II and IV were obtained from
the Center for Disease Control and Prevention (CDC) document: “Background
Document on Gulf War-Related Research” prepared for the Health Impact of
Chemical Exposures During the Gulf War: A Research
Planning Conference in
Addendum D