Massimo Zucchetti * / Red Voltaire
In recent years, science has taken the problems related to depleted uranium and its toxicity. Now should consider the impact it is having the use of depleted uranium in the war against Libya on the environment and health. Reports on its use have appeared in news organs from the beginning of the conflict.
Given their specific physical characteristics, particularly its density makes it extremely sharp, and its low cost production of depleted uranium costs about $ 2 a kilogram (kg) - and the difficulty of their treatment as radioactive waste, depleted uranium has found many great ways to use the military.
If properly treated, the alloy U-Ti (uranium-titanium) is a very effective material for the construction of penetrating elements driven by kinetic energy of dense metal rods capable of piercing armor when used as high-speed projectiles.
spray penetration process most of the uranium, which bursts into incandescent fragments "a violent combustion occurs almost 5 thousand degrees centigrade, when airs across the perforated shield, thus increasing the destructive effect.
pyrophoricity This property is called? Feature found in the sulfur from the matches and domestic matches?. That is, besides its high density, pyrophoricity increases the attractiveness of depleted uranium for various applications, in particular as an incendiary weapon (armor piercing incendiary : element against armor piercing incendiary).
Finally, the phase of impact against the target, the relative hardness of depleted uranium (in a titanium alloy) provides the ability to sharpen the projectile itself. This is the bullet "is not crushed" against the shield-as, for example, with a lead bullet, "but maintains its pointed shape until complete fragmentation, without losing therefore its penetration properties.
Depleted uranium has been used in the battlefields of the Gulf War in 1991, during the bombings of the Atlantic Treaty Organization (NATO)-United Nations Organization (UN) against the Bosnian Serb Republic, in September 1995 against Yugoslavia in spring 1999, and the attack on Afghanistan and Iraq in 2003.
devices use depleted uranium in the wars in Somalia and Bosnia-central and central-eastern particularly in large areas around Sarajevo in early 1990, in Palestine and shooting ranges under the authority military forces of NATO, has been documented incomplete.
Among the weapons that use depleted uranium, it includes also the Tomahawk cruise missile, whose use in the Balkan war in the spring of 1999-although it has not been recognized by NATO, has been confirmed by the has been found at the site, as well as EU sources.
On the other hand, the official manual, given to all the soldiers sent to Kosovo, including recommendations, to be followed to the letter on the presence of depleted uranium in that territory and, in particular, the Tomahawk missile . The manual's introduction states that "military vehicles and equipment Serbs in Kosovo may constitute a threat to the health of the military and civilians in contact with them. Vehicles and equipment that are destroyed, damaged or abandoned must be inspected and handled only by qualified personnel. The dangers of depleted uranium may come as a result of damage caused by the bombing campaign by NATO, in the case of artifacts made directly or indirectly. In addition, the collimators containing tritium (a radioactive isotope) and the instruments and indicators can be treated with a varnish radioactive, dangerous for those who come into contact with the artifacts for inspection. "This appears after a series of tips on how to avoid the explosion of DU.
The manual says: "Avoid any device or material that you suspect may have been hit by munitions containing depleted uranium or Tomahawk cruise missiles. Do not pick or collect depleted uranium munitions found in the field. Notify your post control over the area that you believe that may be contaminated. Wherever you are, delimiting the area contaminated by any material found on the site. If you are in a contaminated area, please, at least the mask and protective gloves. Apply the best personal hygiene. Wash children His body and clothes. "
assessments on the amount of depleted uranium used in the missiles are divergent. vary, in particular, according to various sources, values \u200b\u200bof about 3 kg to about 400 kg. See the note containing the compilation of the different sources can be found on the topic important enough to allow the development of an estimate of environmental impact.
This great variability in the data is easily explained. Some cruise missiles are head reinforced with depleted uranium and some not, but the latter also containing depleted uranium, not the head but in the wings as a flight stabilizer. It can then define two cases:
-high scenario: uranium cruise missile missile in the head: 400 kg of depleted uranium.
-Downside: cruise missile without the presence of uranium in the head, 3 kg of depleted uranium in the wings.
Calculation of impact on environment and health
In the vast literature devoted to the problem of depleted uranium, and had previously addressed the calculation of the uranium radioactive contamination attributable to cruise missiles, particularly those Bosnia fired in 1995. The study is available on the Internet, as in the journal biological and medical Tribune.
If you take the models used, it is possible to deduce the situation on the ground, in places of inhalation, by a calculation intended only to clarify whether the volume of the dose at the site allows downplay the problem.
Considering the impact of a Tomahawk cruise missile carrier rate of 3 kg (at best) or 400 kg (at worst) of depleted uranium.
The impact produced a cloud of debris whose size is variable, after a violent combustion of about 5 thousand degrees Celsius. The dust grains are composed of particles whose dimensions are about one micron (0.5 to 5). A 500 or 1000 meters from the impact point, you can breathe clouds dense enough to cause significant dose, consisting of particles whose mass is about 0.6 to about 5 nanograms (6-50 and 10-10 grams).
An estimate was made following the code GEN II dose calculation, neglecting the effects from fire and considering only the exposure due to inhalation for one hour by simple dispersion of the material, regardless of certain factors that could lead to an increase further exposure. Within an hour, you may inhale radioactive dust grains from the cloud in significant quantities. Many
body fluid and atmospheric dynamics (wind direction, vertical temperature gradient, etc.) can result in relatively small solid angles, pollutant concentrations several orders of magnitude higher, even to those obtained with a uniform dispersion calculation, not compatible with that scenario.
The critical group in this case, happens to be the people "affected" by the cloud of dust grains.
According to an estimate of likely to be exposed in this work, a missile that reaches its target and can burn oxidized particles of dust spread into the environment.
About 70 percent containing depleted uranium missiles? Of which is supposed to be "intelligent" always hit the target? burns. About half is soluble oxide.
The particle size of dust particles that make up the depleted uranium oxide belongs entirely to the type of dust that can breathe, thus creating ultra-fine powder. In particular, the diameter of the particles is, in this case, thinner than the depleted uranium dust from industrial sources, which is common in the middle of the nuclear industry. We speak here of the vast majority of dust content in the range (1-10) micron, which is a significant part of a diameter of 1 micron.
As for the fate of depleted uranium dust on the human body, the main route of absorption is inhalation. A portion of the powder is soluble and another part does not dissolve in body fluids.
Due to the characteristics of depleted uranium oxides of military origin, it is necessary to underline how their behavior differs in relation to industrial dusts of uranium. In any case, it can be assumed, according to the International Commission on Radiological Protection (ICRP, for its acronym in English), that about 60 percent of what is inhaled is deposited in the respiratory tract, and the rest is expelled through the end.
About 25 percent of the microparticles remained in the lungs, it behaves like an M-class material, according to the ICRP, that is slowly soluble in body fluids, the rest is insoluble.
This type of behavior and exposure has not been studied in any previous situation of exposure to alpha emitters in the lungs, has been detected in the civilian environment. The mode of exposure is very different from those that have served as a base when the equivalence between dose and damage in radiation protection.
is totally wrong, but constitute a reference point, extrapolate risk assessments for exposure to such radioactive micropowders from data collected in cases of miners who work with uranium, and in cases of the seriously contaminated by radiation in Hiroshima and Nagasaki. Radiation protection standards of the ICRP are based solely on these experiences and therefore may result in underestimates of risk.
Passing then to other types of toxicity other than radiation, it is then plausible that, given the fine and ultrafine component of depleted uranium dust of military origin, and given the chemical toxicity of uranium, environmental pollution due to Depleted uranium oxides present military source chemical and radiological toxicity. It is necessary to evaluate the synergistic effect of both components.
Thus, radioactivity and chemical toxicity of DU could act together and create an "cocktail" that increases the risk later.
addition to this, Libya's arid climate favors the dispersal of DU particles in the air that civilians continue breathing for years. The main mechanism of exposure to medium and long term has to do with the resuspension of dust and the subsequent inhalation of these.
The methodology and results linked to this model have been published in other papers. Only highlight here the applications and variations of the model applied and already posted:
-The calculation of commitment (half-life) dose is 70, not 50, as recommended by the ICRP.
-approximate data currently is used on the population distribution around the points of impact, also taking into account the primary use of depleted uranium shells in populated areas.
The model results can be summarized as follows:
-Committed Effective Dose Equivalent (CEDE)? Collective dose?: 370 mSvp at 70, and 1 kg of depleted uranium oxidized and scattered in the environment.
-CEDEannual maximum during the first year, MSvp 76, during the second year, 47 mSvp, and during the third year, 33mSvp.
"The route of exposure is inhalation of dust entirely. Are the lungs the body becomes white (97.5 percent of the contribution to the CEDE).
"Among the nuclides responsible, the U238 represents 83 percent of the CEDE and the U234, 14 per cent.
Regarding the total amount of depleted uranium dispersed oxidized in the environment, this assessment is based on data reported by the international press during the first day of the war, the Pentagon says have been fired, along with the British- 112 cruise missiles into Libyan territory. How many missiles will be fired before the end of the war? Since it can not be known, the hypothesis is based on 1 000 missiles so that the reader can readily estimate the impact on the environment and health by a rule of three, which include the exact number of missiles that are carried at the end of conflict .
If the heads of all the missiles were "deprived" of depleted uranium, we would have an amount of 1 000 by 3, which is equal to 3 000 kg, equivalent to 3 tonnes of depleted uranium (at best).
If all heads have missiles with depleted uranium, would have an amount up 400 000 kg, or 400 tons of depleted uranium.
assessing the gravity, just compare that data with the 10 or 15 tons of DU were fired in Kosovo in 1999. Assuming that about 70 percent of the uranium is burned and spread into the environment, so you get an estimate of the amount of depleted uranium oxide equal to 2.1 tons (at best) and 280 tonnes ( the worst). This allows estimating a CEDE (collective dose) for the entire population equivalent, in the best case, 370 mSvp / kg, 2 000 100 kg SVP approximately equal to 780, in the worst case, 370 mSvp / kg and equal to 280 000 kg 104 000 SVP, approx.
is not correct, but constitute a reference point, extrapolating assessments by exposure to such radioactive micropowders from radiation protection standards of the ICRP, which are adopted for the GEN II code. If you still applies here also the rate of 6 percent Sv-1 for the risk of tumors, we get about the best, around 50 cases of tumors under 70 years, at worst cases, about 6 000 200 cases of tumors under 70 years.
Conclusions The risks of exposure to depleted uranium that runs the Libyan people as a result of using this substance in the war of 2011 have been evaluated with the broadest possible approach, trying to take into account some recent results of studies on the subject.
This type of exposure has not been studied in any previous situation of exposure to alpha in the lungs that are found in the civilian environment.
However, the assessment has been made of the doses and associated risk in both situations (depending on whether the missiles "without uranium" or "uranium") allows certain conclusions wound.
In the first case (the best) Expected number of tumors is very low and absolutely not significant from statistical point of view. This statistical difficulty has nothing to do with an acquittal of such practice, acceptance and even less with an assertion that has little importance, or it can be safe. By contrast, in the second case (the worst), there are a number of tumors which stands at several thousand. These tumors reach a level course epidemiology.
is necessary, therefore, that the armies which were bombing Libya clarify actual tests, not comfortable statements, the presence or not and in what quantities, depleted uranium missiles. In the past, there were "official denial" about the presence of uranium in cruise missiles. However, as these denials from military means, was classified, at least with some caution.
Based on data that are public, estimates of the development of tumors in the coming years in Libya are due to this totally unjustified practice, quite disturbing. The discussion about the relative incidence of each of the teratogens used in a war (chemical, radioactive, etc.) appears unimportant and even disrespectful: the dead in Libya because of this attack and exceed beyond any number that may one day be defined as "the necessary price."
is important, finally, collect data and studies, there are many, on the effects of "new wars" have on the man and the environment. You have to show how modern weapons, which have nothing in "surgical" cause unacceptable harm. We must consider the impact they have had, in men and in the environment that have suffered war, "humanitarian" recorded since 1991.
* Professor of nuclear facilities in Turin Polytechnic Institute; Course holder Security and Risk Analysis and Radiation Protection
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