Verbatim account of presentationby Dr. Baverstock
Introduction
Health effects of a manmade toxin DU oxide dust, which is formed from DU metal when a
bullet or bomb hits a hardened target and burns, does not occur naturally.
The material has no natural analogue. Scientists cannot compare it with
anything else. One has to look at DU oxide on its own merits, or see what
can be learned from what is known about the basic effects of uranium on
health. Uranium is toxic like many other heavy metals. This is known from
the early days of uranium processing. Workers were exposed to dust of
yellowcake, which is a soluble oxide of uranium and an intermediate in the
processing and purification of uranium. It is known that the workers
suffered kidney problems. Dr. Baverstock is considering the long-term problem
that you might have, living in an environment that is contaminated with
the dust from burnt depleted uranium (DU). The principle concern of Dr.
Baverstock with this DU oxide has been the public health interest. He
stresses this because there is another group than the public, the
combatants, who also are exposed to DU, but much closer and in much higher
concentrations. He is sure that there are health effects there, but he has
not considered those. In 2000 the WHO was preparing its monograph on the
health effects of DU oxide. Dr. Baverstock
looked to see whether there would be a case that the WHO ought to
investigate this DU more closely. He decided that this was the case and he
invited two colleagues, Dr. Mike Thorn and Dr. Carmel Mothersill, to join
him in exploring this and writing a publication. That publication is the
basis for his speech and this report. Damage by DU on organ level
Uranium dust from rock is toxic to the lung There is some experience with health effects of
unprocessed natural uranium, as an insoluble oxide in rock dust, from the
uranium mining industry. There is confidence that there is a degree of
toxicity for this inhaled material. But the toxicity is not very great.
But then, only part of this material is in fact uranium. The rest is rock
of various kinds. Also, this uranium is highly insoluble, and therefore
retained in the lung. Altogether there is a kind of diluted uranium, which
is highly insoluble. If one looks at the lungs of diseased coal miners or
uranium miners, one will find that the deep lung in particular is very
heavily coated with these insoluble particles or dust. It is accepted as a
hazard, but not as a tremendously serious one. DU oxide dust is also toxic to the bone and
the kidney DU oxide dust, produced from depleted uranium, is
quite different than the above mentioned natural uranium. This dust is a
100% depleted uranium oxide and also has a soluble component. Mostly it is
not very soluble, but very slowly, sparingly soluble. This soluble part
gets translated through the blood and enters the bone through the bone
marrow cavities. Dr. Baverstock supposes that there is a potential for
leukaemia by this process. Eventually the DU gets to the kidney and is
excreted, but that could be after quite a long period of time. Scientists
understand how uranium produces damage to the kidney: uranium prevents the
re-uptake of water, or slows up this re-uptake, leading to a greater
amount of excretion of water. A study by a group in Finland has found uranium in
the urine of Fins who are drinking water from wells, where there is a lot
of uranium in the water. The males in particular excrete something which
probably has to do with bone formation. So there could be a toxic effect
on bone as well and that is quite consistent with the fact that once
uranium gets into the blood it gets into bone. Damage by DU on the cellular level
1. Genetic damage by a-particles A DU oxide dust particle will emit a-particles, a
particular kind of radiation. This radiation has a very small penetration,
but a lot of energy. An a-particle travels around 40 microns, which is
only about 3 or 4 cell diameters, and releases about 5 MeV of energy. This
is a very short range and a lot of energy is deposited in a very small
volume. A DU particle of the size that may be retained in the lung emits
an a-particle between once a week and once a month, depending on the size
of the particle. Uranium has a very low specific activity. But these
emissions of a-particles have an effect: chromosomal aberrations,
mutations, micro-satellite damage, are examples of damage that can occur
in irradiated cells. 2. Toxic damage by soluble depleted uranium DU oxide dust particles are partially soluble.
Soluble DU migrates very slowly through the cells away from the particles,
because DU binds quite effectively to cellular constituents like protein
and DNA. Micron-sized particles, deposited in the deep lung, will clear
very slowly from there. The concentration of DU around the particle is
transiently high due to the dissolution over a period of weeks to months
during which it is transferred to the bone and then the kidney Evidence came from the Armed Forces Radiation
Research Institute (AFRRI) in Bethesda (US) indicates that there is a
genotoxic effect in cells exposed both to soluble and insoluble DU. This
is observed in laboratory studies and in soldiers who have fragments of DU
in their bodies. In cell culture experiments soluble DU and insoluble DU
oxide converted cells into a transformed state. When these cells were
injected into mice they caused malignancy. Precisely the same effect was obtained using using
nickel, another heavy metal, which is not radioactive, but toxic like
uranium and a well established carcinogen. The toxic effect of uranium on the kidney is
physiological; the uranium changes the structure of the kidney and causes
it to misfunction. For these reasons Dr. Baverstock thinks it is
reasonable to suspect that DU has a chemical genotoxic effect too, and
thinks that this effect of DU is now a well established phenomenon. Many
chemicals are tested for their carcinogenicity by exactly these kind of
tests. If they produce transformations in the tests, they are potentially
carcinogenic. 3. Damage by synergism Synergism occurs when two agents have an effect
individually and a more than additive effect when present together. An
example of a synergism is with radiation and smoking. The effect of the
radiation and the chemical effect of the cigarette smoke produces a
greater risk if the two are present together. In the case of DU the
combined effect of the alpha particles and the chemical toxicity might
well be more than additive. The synergistic effect may also, at least in
part be a transient effect. 4. Toxic damage by the bystander effect Having started out as an extreme sceptic, Dr.
Baverstock came to accept the phenomenon of the so-called bystander effect
several years ago. The theory is relatively new but within the last 10
years it has been well established. The bystander effect was uncovered,
not discovered. If one looks back in the literature one finds a lot of
earlier evidence. It could have been interpreted as the bystander effect,
but the evidence was just ignored because the dogma did not allow for the
effect. It was a real battle for Carmel Mothersill and Colin Seymour, to
get the bystander effect accepted by the scientific community. However, it
was not their experiment that led to the general acceptance of the
phenomenon was carried out at Harwell. The bystander effect takes place as follows: If one cell is irradiated with an a-particle it is
expected to see the effects of radiation in that cell, but it turns out
that some of the neighbouring cells can also start to behave as if they
have been irradiated. In other words, they show the typical effects of
radiation, such as specific mutations. It is believed that cells send out
chemical signals to their neighbours and these chemical signals induce the
bystander effect. In the mechanism of the bystander effect, two
processes are known. One is through so-called gap junctions, connections
which carry very small molecules between cells. Gap junctions are little
tunnels or tubes between adjacent cells and small molecules can pass
through those to induce the effect in adjacent cells. The second process
is established from experiments by Carmel Mothersill. In this case cells
are irradiated in growth medium and the irradiated cells filtered off and
fresh cells put into the medium. One sees "radiation effects" in
the fresh cells without them having been irradiated. Apparently the medium
contains something which causes the bystander effect, possibly the same
molecules transferred through the gap junctions. The exact mechanism of the bystander effect is
unknown but according to Dr. Baverstock there is growing evidence that the
bystander effect is involved in a malignant response. It is not necessary
to be too concerned about the mechanism. The argument is that the effects
produced by the bystander effect are the same as the effects produced by
ionising radiation and ionising radiation is a carcinogen. It is
reasonable to assume that there is a potential risk of malignancy from the
bystander effect. Testing of DU poisoning
To test for DU is not simple The metabolism of uranium through the body is a
very complicated process. It is not simple to relate what comes out in
urine to what went in at the during exposure as that depends many factors
including the time of intake and the exact nature of the exposure. First
the uranium has to dissolve from the particle in the lung, then through
the blood supply be translocated to the bone, then be resorbed from the
bone to the blood and pass through the kidney into urine. This pathway is
very complex and the process will take several weeks to
months. In practice it is most unlikely that exposure will be a
singular event so level in urine are difficult to relate to exposure,
unless tests are performed sequentially over several months. Quantitative test and background level Soldiers that have been exposed to DU oxide dust
should ideally be tested on their background level of U before exposure.
Urine tests on the background can level still be done after a suspected
exposure, eg the first week, because there has not been time for inhaled
uranium to get into the urine yet. This background level can be compared
with the levels later on to determine whether there has been an exposure.
The urine test should also be done at intervals much later on. For sure,
exposure to DU is seen in a difference in the overall level of uranium.
This straight uranium test, over a period of months after the exposure, is
also a good indicator of DU contamination if the level of uranium goes up
with time. Qualitative test Ideally, but it might not be necessary if the
exposure is high enough, soldiers should be tested for the isotopic ratio
of uranium as well. DU will give rise to a different isotopic ratio
between uranium 235 and 238, compared with the natural situation. From the
natural sources the ratio U235/U238 is 0.0073, while DU has a value of
around 0.0020. This isotopic ratio can be measured with mass spectrometry.
This test is much more expensive, typically a €1000 for each
measurement. The test is not tremendously sensitive. ICRP models are unreliable
The ICRP works mostly with models Calculation or estimation of radiation risks is
guided by advice from the International Committee on Radiation Protection
(ICRP), the International Atomic Energy Agency (IAEA) and the World Health
Organisation (WHO). The ICRP has derived models relating risks to
radiation dose. These models are constructed on the basis of
epidemiological studies of the risk of cancer seen in the survivors of the
atomic bombings in Japan even though the the exposure characteristics of
internal exposure are very different from in those in Japan. Thus,
radiation risks are mostly derived from models and not direct observation. CERRIE report criticises ICRP models Recently, the models of the ICRP have been
criticized by a committee in the United Kingdom. The publication states
that internal irradiation risks may well have an uncertainty much greater
than that which the ICRP presently admits to. This might be in fact a
factor of ten in either direction and in a few case much more, a tenfold
underestimation or a tenfold overestimation, depending upon the situation. In the report DU was interestingly enough not
identified as one of the issues, but Dr. Baverstock thinks that this is
one example where the risk is underestimated probably by the ICRP. The ICRP models ignore the chemical toxicity
of DU It is a big problem that the ICRP only looks at the
risks of radiation effects and ignores the risks of chemical effects.
Therefore, only the contribution of the first effect, the a-particles, is
dealt with, and therefore the risk of DU considered very small. DU oxide dust is treated as if it is totally
insoluble. Solubility is not considered at all, so the toxicity of the
other three effects can completely be neglected. The impact of such a minimal interpretation can be
found for instance in climate differences and the risk from re-suspension
of DU oxides in the environment. In Iraq the climate is very arid and dry,
so the soluble component of the DU oxide particles in the environment do
not get washed or weathered by the rain. Also DU has been found inside
buildings, in Baghdad for example. Such DU particles still have their
soluble component. In Dr. Baverstock's view, re-suspension is not so
important in the much less arid climate of the Balkans, but is important
in Iraq. An attack on a single tank might produce a few kilos of DU dust.
The DU particles that have fallen to the ground become available for
inhalation again and again, when blown by the wind or when vehicles pass. A deliberate blind eye The issue of independence of the official
institutions has to be questioned. The ICRP, the IAEA and the WHO continue
to admit only part of the risk, apparently ignoring the evidence from the
work at the Armed Forces Radiation Research Institute. Radiobiological
protection regulation depends on models and there has been is no attempt
to update these models in the light of the new information. What we have instead is a social judgement, that
the risk in the context of the usefulness of DU is in fact an acceptable
risk. This judgement is made on the behalf of those who are exposed to the
risk, not on behalf of those doing the regulating, of course. It is a
choice to not interpret the new information, not to include it in ones
calculations. Dr. Baverstock cannot understand why the ICRP and
the IAEA in 2003 could ignore the evidence which was available in 2000 and
2001, without incorporating it into their risk assessments. The position
of the ICRP has to be to address the DU problem. The ICRP has to make a
full risk assessment including the chemical toxicity and the synergistic
effects, because at the moment radiation is treated separately from
toxicity in their models. In the case of DU, a potential effect is missed
by doing that. It has to be a deliberate "blind eye", because
these institutions have access to all the evidence. Economical and political pressure There are thousands to hundred of thousands of
chemicals in use in modern society and very many different exposure modes
to radiation and radioactiivty. Epidemiological surveys of each of these
risks would not be practicable so regulation and the declaration that a
chemical or exposure route to radiation or radioactivty is carcinogenic
has mostly to be based on models. There is no doubt that there is political pressure
on organisations like the ICRP, IAEA and WHO. The countries hold a key to
this. For example, member states tell the UN to be free and independent,
but only as long as it does what is required. And that is particularly
true of the UK and the US. This political pressure is always
"understood", never explicit. Pressure is also applied through
"wheeling and dealing". Dr. Baverstock is sure that in the case
of the WHO, the then Director General, Mrs. Brundtland, was often faced
with such a situation. In return for support in one aspect, the tobacco
initiative for example, less attention would be given to other aspects.
Often it is a conflict between economic progress and the environment. This
pressure, coming from the economic side, is driving the system off its
course. Politicians should give real freedom to these organisations,
instead of putting pressure on them. These institutions can only become independent if they are
not pressured. He is sure that is the problem. Other difficulties with proof
Acknowledgement of diverse symptoms There might be a situation in the long term in an
environment where DU gets re-suspended into the air. Civilians could
breathe large quantities of DU oxide dust. There is no agreement that the
symptoms of people who have been exposed in this way are due to DU. There
is a suspicion that symptoms are there because of exposure. That is the
connection, but the problem is that the symptoms are often fairly diverse.
No two people have exactly the same symptoms. Very different symptoms have
been claimed, especially in the case of veterans who might have been
heavily exposed: excessive tiredness, skin rashes, headaches and muscular
weakness. There is a very interesting parallel, around twenty
years ago in Spain, there was something known as the toxic oil syndrome.
Evidently contaminated rape seed oil was sold and some 20,000 people
suffered illness, some very severe illnesses and 800 died. It was due to a
toxicological response of some kind, but the toxin has never been nailed
down. Even now, it is not exactly clear what symptoms are directly
associated with the toxic oil syndrome as these symptoms were rather
diverse. "Dilution" effect in epidemiology
and statistics Exposure to DU could very patchy where soldiers are
concerned. It is possible that only some of the soldiers in an area would
be exposed. If soldiers have died of cancer, it is not immediately clear
how many of them were actually exposed to DU even if they were in the
vicinity where others were exposed. In the follow-up of such a mixed group
the effect can diluted by the people that actually have not been exposed. This kind of dilution effect is a problem that
often arises when measurements are done in a group. People who were
nearby, but not actually exposed, lead an underestimation of the result.
This allows others to say: well, a few problems but not enough for
action to be taken. Dr. Baverstock thinks that epidemiology often falls
into this trap. It has often been convenient to look at a larger group
than just the exposed and hence miss an important health effect. So, in
examining groups one has to be very careful to select only those people
who actually have been exposed. The same problems with patchy exposure applies to a
realistic environmental measurement, it has to be clear were the exposure
is. Laboratory conditions Urine measurements on DU have to be really made
under laboratory conditions. If urine samples are taken in an environment
which is contaminated with uranium one will get high values in the
samples, just from external contamination. In the Iraq situation, it will
be very difficult to take realistic, biological samples. Depleted uranium
would be found in the environment, therefore it is not really feasible to
test in Iraq right now. Credibility and stress If a message of concern is raised, the message has
to be true. People become unnecessarily stressed if they believe they are
living in a highly contaminated environment if indeed they are not. Their
lives become very difficult. From the public health point of view that is
damaging. The prevailing economical argument
Compensation is expensive To be compensated for something, one usually has to
show that there has been an exposure which has caused symptoms. It is not
enough to say that there has been an exposure. In the case of soldiers who come into contact with
DU in cleaning up operations, the hazards are extremely high and
compensation would be expensive. Compensation could be a factor driving
the military authorities away from using DU. But also to completely
discard equipment such as tanks and everything that was in them is also a
very expensive way of conducting business.
There is the public concern and the concern of the soldiers
themselves but the economic factors, rather than the humanitarian views,
would seem to be more likely to influence the military authorities over
the use of DU. Compensation of Pacific veterans In the case of American veterans involved in
nuclear testing in the Pacific, there is a list of thirteen cancers. If
veterans have one of these thirteen cancers, and they have been in that
area where weapons were detonated, then they are compensated, whether that
cancer was actually caused by the radiation or not. The veterans are
deemed to be in a compensatable position. Possible action
Ask the right questions A basic question for Dr. Baverstock is: what are we
looking for proof of? Are we looking for proof that there is an effect, or
are we looking for proof that there is not an effect? Because these are
two completely different questions. Lawyers and politicians have to be
very clear about this. He thinks that in the case of DU compensation,
there is a kind of precedent that can be exploited by lawyers and
politicians. Precautionary p If a risk is suspected, or there is reasonable
suspicion that there might be a risk, one is also supposed to apply the
precautionary principle. In the case of uranium weapons Dr. Baverstock
believes that the precautionary principle would require cleaning up
battlefields quickly after the battle, before the material spreads. The
Geneva Convention states that civilians should not be at any health risk
as a result of things left over from the battle. He believes that
the Convention ought to include DU. When the military are working to clean up they take
full precautions. When the US military clean up a tank, full protective
clothing for the skin and a breathing apparatus to prevent inhalation of
the material is used. This is not required of the public living in the
region where this material is deposited. According to Dr. Baverstock a precautionary
approach is definitely needed, but very costly. Actually abandoning DU
would be a better solution. Costs are a realistic argument for a ban, and
a ban may well be what will happen. Independent research Out of a lot of issues mentioned, Dr. Baverstock
liked the suggestion that the Socialist Party in the Netherlands might
take up some kind of investigation on an independent basis. There is a
fear that if one approaches two scientists and asks them the same
question, this will result in two different answers. That is solved when
these people are brought together in the same room and discuss the issue
with one another. When Dr. Baverstock, for example, is put in the same
room as people from the IAEA and the ICRP, he would ask why they do not
use the actual data on chemical toxicity. They would have to give a very
good reason which would ultimately be made public. Empowering the military unions Dr. Baverstock thinks the military union is
absolutely right to be concerned. He supposes that the union could
negotiate, if not insist, on having proper measurements taken to protect
military personel where they may be exposed to DU. |