Nuclear Radiation – Incompatible with Life

Eiichiro Ochiai – from Nuclear Issues in the 21st Century – Invisible Radiation Effects on Life,As argued in this whole book, the basic reason for “NO NPP on the Earth” is “Radiation is Not Compatible with Life”. What this means is that life cannot defend itself against the damaging effects of radiation. This has been true throughout the whole history of life on earth, though such effect by the naturally occurring radiation is minimal, and cannot be identified as such unless careful and systematic studies are conducted. This issue is discussed in chapter 11.
The radiation effects on human health have increased since the human started to add radioactive materials artificially to the environment. This is a fact, and needs to be recognized by the entire human race,
Very Small Quantity of Radioactive Nuclides can be Lethal
It was argued in section xxx why external exposure of such a small energy (10 Gy) is lethal. This energy is to raise the body temperature by only 0.0024 degrees. The following is an example of lethal internal radiation caused by a much smaller radiation exposure.
One of the Bandazhevsky investigations showed that the Cs-137 Bq value in the heart was 200 Bq/kg on average in those died from heart failure after Chernobyl accident [Fig. 8.x on original]. This radioactivity is caused by 6 x 10-11 g of Cs-137. If the body (heart) was exposed to this radiation activity for a year, the exposure dose would have been about 1 mGy/kg. In terms of ICRP and other such organizations’ estimate, this low level exposure should have no significant health effect. The fact is that it was lethal. This radiation source emitted 6.3 x 109 radioactive particles. Assuming 1 MeV per particle, the exposure would have destroyed about 1 x 1014 molecules in the heart cells. Some critically important molecules for heart activity could have been destroyed; hence heart failure and death.
This is to illustrate how small quantities of radionuclides can be lethal. If this argument is reasonable, even smaller quantities can be supposed to be able to cause serious diseases, including cancers.
he operation of NPP inevitably produces a large amount of radioactive material. Typically 3-4 kg of U-235 will be burned per day at a NPP, so that a NPP burns about 1 tons of U-235 per year. The basic problem is to dispose safely the radioactive nuclides.
The wastes we produce, whether biological or industrial, can be dealt with. The biological wastes can be thrown into “toilet”, after which they are processed chemically, biologically, otherwise and eventually returned in harmless forms back to the environment. They can be used as manure, as well. Or animals’ wastes are collected and dried, and then used as fuel without any harm to people in certain regions. These ways of dealing with the wastes are possible because they are chemicals. Of course the problems are not simply theoretical matters, and are big problems in reality, as exemplified by the “plastic wastes”.
NPP have no toilet for its radioactive wastes; the spent fuel rods are typically stored in cooling pools. The radioactive wastes produce both heat and radiation through decaying processes. When the fuel rods become sufficiently cool after certain period of time (years), they would be transferred into sturdy containers being cooled by air, and no further treatment. Well they are supposed to be deposited in deep caves where they would be left in forever. The basic problem with radionuclides is that we, chemical means, cannot change them to the non-radioactive. Therefore, they are left radioactive; some of them last million years (see Fig. 24.1). How safely they are stored in such places (deep cave, etc) is a good question. Geological activities may damage the containers or radioactivity may be enough to damage the containers for such a long period (may feel forever for human race).
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