5.
Depleted uranium is said to have low level radiation as compared to the nuclear weapons. It is also pointed out that gamma rays caused major damage in the radiation from the atomic bomb while the alpha rays cause the damage in the depleted uranium. What is the difference in the damage caused by alpha rays as compared with those of gamma rays?
"Heat not a furnace for your foe so hot
That it do singe yourself."
William Shakespeare (1564–1616)
Faulty A-Bomb Studies – Poor Risk Model
Gamma rays have been called the major cause of damage from nuclear weapons, but other effects (internal contamination, internal dose to individual cells, diseases other than cancer etc.) were ignored or not considered in official A-bomb studies. Criticism of the A-bomb studies has not been limited to Dr. Alice Stewart1 who pointed out that the first five years (and more) of Hiroshima and Nagasaki data was not included in the official studies. A recent European Parliament report, ECRR 2003 Recommendations of the European Committee on Radiation Risk2, by the European Committee on Radiation Risk (ECRR) reports that A-bomb studies underestimate the radiation risk by more than 1000 times and failed to consider internal exposure and diseases other than cancer [see “Executive Summary” quote below].
Nuclear Weapons vs. DU Weapons: An alpha particle… is an alpha particle… is an alpha particle…
It is important to understand that nuclear weapons work from the outside in (flash gamma exposure and later internal exposure from fallout), and depleted uranium (DU) weapons work from the inside out (low level radioactivity outside the body but very high internal exposure due to the localized effect). Nuclear weapons and DU both release energy from the nucleus (nuclear energy) but in different ways. Nuclear bombs involve a process that destabilizes the atoms by bombarding the nuclei with neutrons. The atoms fragment, releasing the energy in the nucleus instantaneously, in a cascade (not a chain reaction). When the atoms tear apart, they fragment into radioactive isotopes forming man-made isotopes of elements on the periodic chart, many of which do not occur in nature. The energy that is released from the nucleus is released as alpha, beta, gamma. These particles and rays have a set of energies3 which are characteristic of the particular isotope.
In the case of natural (the uranium isotopes in DU) and man-made radioactive decay, the rate of decay determines the half-life of the isotope. The energy that is released from the nucleus is also alpha, beta, and gamma rays, with their own discrete energies characteristic of the isotope. DU can be considered a radiological weapon4, because it releases the energy in the nucleus by natural “radiological” decay. And it can be considered a “nuclear” weapon because the energy is derived from the nucleus of the atom. The alpha particle has certain energies that are unique to a particular isotope. Beta particles have a spread of energies from 0 to the maximum (Fermi-Durac distribution), the maximum is given as the number that characterizes the beta spread. Gamma rays have a discrete set of energies which identify that isotope.
Fission Products and Natural Decay Products
Nuclear bombs release nuclear energy in a fission process which is almost instantaneous. Nuclear reactors release energy in a slow or controlled fission process. The fission process for nuclear bombs and nuclear reactors release the same fission products in the same proportions but at different rates. DU releases energy by natural decay, which is very slow because of the long half-life of Uranium-238 (4.5 billion years). However, the three uranium isotopes that make up DU transform into other radioactive isotopes2 in four steps before they become lead. The daughter products are much more radioactive than Uranium-238, which means that as DU transforms, the specific radioactivity of the daughter products increases by millions of times. It increases the internal exposure by magnitudes, and this happens in four transformations for a single atom before it is no longer radioactive. The alpha particle dose to a single cell from Uranium-238 is 50 times the annual dose limit. Cancer begins with a single alpha particle, beta, or gamma ray.
In 1950 THE EFFECTS OF ATOMIC WEAPONS (reprinted in 1977 as the U.S. Army manual on THE EFFECTS OF NUCLEAR WEAPONS5) recognized the danger of alpha particles from uranium and plutonium. The atomic bombs dropped on Hiroshima and Nagasaki (“Fat Man” and “Little Boy”) contained large amounts of depleted uranium as “tamping” or reflector material. The diameter of “Fat Man” was five feet, nearly all of it was depleted uranium:
9.40 “…The uranium and plutonium which may have escaped fission in the nuclear weapon represent a further possible source of residual nuclear radiation….”
9.41 “The alpha particles from uranium and plutonium… are completely absorbed in an inch or two of air…. indicates that uranium and plutonium deposited on the earth do not represent a serious external hazard.”
9.42 “Although there is negligible danger from uranium and plutonium outside the body, it is possible for dangerous amounts of these elements to enter the body through the lungs, the digestive system, or breaks in the skin. Plutonium, for example, tends to concentrate in bone and lungs, where the prolonged action of the alpha particles can cause serious harm.” 5
Evolution of Health Protection Standards – Using a blender to hide local effects
As research over the years revealed the hazard of ionizing radiation, the evolution of health protection standards for nuclear workers became incrementally more conservative6 (See chart below). The ECRR report and others7 argue convincingly that there is no safe limit (threshold) for exposure to radiation. Many studies8,9on exposure to low level radiation around nuclear power plants document the effects. It is clear from these and other studies2 that the impact of chronic exposure to low level radiation is greater than what would be expected based on the risk model from A-Bomb studies. Low level radiation has an effect, per unit of radiation, that is greater than at higher dose rates. This is called the “supralinear” effect2 (see p. 79). From studies on Chernobyl victims, ultra-low level exposures are also a greater risk than previously thought2.
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Depleted uranium is said to have low level radiation as compared to the nuclear weapons. It is also pointed out that gamma rays caused major damage in the radiation from the atomic bomb while the alpha rays cause the damage in the depleted uranium. What is the difference in the damage caused by alpha rays as compared with those of gamma rays?
"Heat not a furnace for your foe so hot
That it do singe yourself."
William Shakespeare (1564–1616)
Faulty A-Bomb Studies – Poor Risk Model
Gamma rays have been called the major cause of damage from nuclear weapons, but other effects (internal contamination, internal dose to individual cells, diseases other than cancer etc.) were ignored or not considered in official A-bomb studies. Criticism of the A-bomb studies has not been limited to Dr. Alice Stewart1 who pointed out that the first five years (and more) of Hiroshima and Nagasaki data was not included in the official studies. A recent European Parliament report, ECRR 2003 Recommendations of the European Committee on Radiation Risk2, by the European Committee on Radiation Risk (ECRR) reports that A-bomb studies underestimate the radiation risk by more than 1000 times and failed to consider internal exposure and diseases other than cancer [see “Executive Summary” quote below].
Nuclear Weapons vs. DU Weapons: An alpha particle… is an alpha particle… is an alpha particle…
It is important to understand that nuclear weapons work from the outside in (flash gamma exposure and later internal exposure from fallout), and depleted uranium (DU) weapons work from the inside out (low level radioactivity outside the body but very high internal exposure due to the localized effect). Nuclear weapons and DU both release energy from the nucleus (nuclear energy) but in different ways. Nuclear bombs involve a process that destabilizes the atoms by bombarding the nuclei with neutrons. The atoms fragment, releasing the energy in the nucleus instantaneously, in a cascade (not a chain reaction). When the atoms tear apart, they fragment into radioactive isotopes forming man-made isotopes of elements on the periodic chart, many of which do not occur in nature. The energy that is released from the nucleus is released as alpha, beta, gamma. These particles and rays have a set of energies3 which are characteristic of the particular isotope.
In the case of natural (the uranium isotopes in DU) and man-made radioactive decay, the rate of decay determines the half-life of the isotope. The energy that is released from the nucleus is also alpha, beta, and gamma rays, with their own discrete energies characteristic of the isotope. DU can be considered a radiological weapon4, because it releases the energy in the nucleus by natural “radiological” decay. And it can be considered a “nuclear” weapon because the energy is derived from the nucleus of the atom. The alpha particle has certain energies that are unique to a particular isotope. Beta particles have a spread of energies from 0 to the maximum (Fermi-Durac distribution), the maximum is given as the number that characterizes the beta spread. Gamma rays have a discrete set of energies which identify that isotope.
Fission Products and Natural Decay Products
Nuclear bombs release nuclear energy in a fission process which is almost instantaneous. Nuclear reactors release energy in a slow or controlled fission process. The fission process for nuclear bombs and nuclear reactors release the same fission products in the same proportions but at different rates. DU releases energy by natural decay, which is very slow because of the long half-life of Uranium-238 (4.5 billion years). However, the three uranium isotopes that make up DU transform into other radioactive isotopes2 in four steps before they become lead. The daughter products are much more radioactive than Uranium-238, which means that as DU transforms, the specific radioactivity of the daughter products increases by millions of times. It increases the internal exposure by magnitudes, and this happens in four transformations for a single atom before it is no longer radioactive. The alpha particle dose to a single cell from Uranium-238 is 50 times the annual dose limit. Cancer begins with a single alpha particle, beta, or gamma ray.
In 1950 THE EFFECTS OF ATOMIC WEAPONS (reprinted in 1977 as the U.S. Army manual on THE EFFECTS OF NUCLEAR WEAPONS5) recognized the danger of alpha particles from uranium and plutonium. The atomic bombs dropped on Hiroshima and Nagasaki (“Fat Man” and “Little Boy”) contained large amounts of depleted uranium as “tamping” or reflector material. The diameter of “Fat Man” was five feet, nearly all of it was depleted uranium:
9.40 “…The uranium and plutonium which may have escaped fission in the nuclear weapon represent a further possible source of residual nuclear radiation….”
9.41 “The alpha particles from uranium and plutonium… are completely absorbed in an inch or two of air…. indicates that uranium and plutonium deposited on the earth do not represent a serious external hazard.”
9.42 “Although there is negligible danger from uranium and plutonium outside the body, it is possible for dangerous amounts of these elements to enter the body through the lungs, the digestive system, or breaks in the skin. Plutonium, for example, tends to concentrate in bone and lungs, where the prolonged action of the alpha particles can cause serious harm.” 5
Evolution of Health Protection Standards – Using a blender to hide local effects
As research over the years revealed the hazard of ionizing radiation, the evolution of health protection standards for nuclear workers became incrementally more conservative6 (See chart below). The ECRR report and others7 argue convincingly that there is no safe limit (threshold) for exposure to radiation. Many studies8,9on exposure to low level radiation around nuclear power plants document the effects. It is clear from these and other studies2 that the impact of chronic exposure to low level radiation is greater than what would be expected based on the risk model from A-Bomb studies. Low level radiation has an effect, per unit of radiation, that is greater than at higher dose rates. This is called the “supralinear” effect2 (see p. 79). From studies on Chernobyl victims, ultra-low level exposures are also a greater risk than previously thought2.
Please continue ...