CONTROVERSES NUCLEAIRES !
ACTUALITE INTERNATIONALE
2008

juin
1) Une parade à l'irradiation
Sciences et Avenir, Scientific American
2) Radiation for health: Could exposure to low doses of radiation cure our ills?
Les radiations, bonnes pour la santé!?
Inderscience Publishers
Sources ADIT
     1) Sciences et Avenir Des chercheurs américains ont mis au point un produit qui protège les tissus sains des rayons ionisants, atténuant les effets secondaires de la radiothérapie.
     L'avis de Patrick Gourmelon (IPSN): "Ce produit est le meilleur radioprotecteur au monde. Il est fascinant que ce produit protège le système digestif, un organe particulièrement sensible aux rayonnements, pour lequel nous ne pouvions rien faire auparavant."
http://www.sciam.com
Protecting Cells From Radiation
Scientists remain on the lookout for novel drugs that combat radiation damage.
     One of the most promising is CBLB 502, made by Cleveland Biolabs in Buffalo, N.Y.  [see "Surviving Side Effects"; SciAm, October 2007].
     In the April 11 Science, researchers report that the drug, also called Protectan, enabled 87% of mice to survive lethal doses of radiation, although it worked only if injected within an hour before exposure. (It showed some protective effects if injected after exposure to lower levels of radiation.)
     The compound, which could be given in the event of a nuclear explosion or meltdown, did not shield malignant cells, so it could protect healthy cells of cancer patients undergoing radiation treatment. The company now needs to test the agent in large numbers of people.
Commentaire Gazette nucléaire:
    Ce sont des produits dont on ne connaît pas les effets secondaires. Ils sont très intéressants pour les irradiations médicales, il ne faudrait pas que les médecins en profitent pour faire n'importe quoi. Ils doivent être administrés avant, donc en cas d'accident, c'est juste un traitement, mieux vaut celui des cellules souches. Quant aux faibles doses elles ne sont pas concernées, car les mécanismes sont différents...

     2) Radiation for health
Could exposure to low doses of radiation cure our ills?
Contact: André Maïsseu
     a.maisseu@wonuc.org
     Inderscience Publishers

     For decades, we have been told that exposure to radiation is dangerous. In high doses it is certainly lethal and chronic exposure is linked to the development of cancer. But, what if a short-term controlled exposure to a low dose of radiation were good for our health. Writing in today's issue of the Inderscience publication the International Journal of Low Radiation, Don Luckey, makes the startling claim that low dose radiation could be just what the doctor ordered!
     Luckey, an emeritus professor of the University of Missouri, was the nutrition consultant for NASA's Apollo 11 to 17 moon missions and has spent the last several years developing the concept of improving health through exposure to low-dose radiation.
     "When beliefs are abandoned and evidence from only whole body exposures to mammals is considered, it becomes obvious that increased ionizing radiation would provide abundant health," Luckey explains. He suggests that as with many nutritional elements, such as vitamins and trace metals it is possible to become deficient in radiation. "A radiation deficiency is seen in a variety of species, including rats and mice; the evidence for a radiation deficiency in humans is compelling."
     In the first part of the twentieth century at a time when our understanding of radioactivity was only just emerging, health practitioners began to experiment widely with samples of radioactive materials. Then, exposure to radiation, rather than being seen as hazardous, was considered a panacea for a wide variety of ailments from arthritis to consumption.
     The discovery of antibiotics and the rapid advent of the pharmaceutical industry, as well as the fact that it became apparent that exposure to high doses of radiation could be lethal led to the demise of this "alternative" approach to health.
     Today, radioactivity is used in targeted therapies for certain forms of cancer, however, the use of radiation sources for treating other diseases is not currently recognized by the medical profession.
     Luckey hopes to change that viewpoint and argues that more than 3000 scientific papers in the research literature point to low doses of radiation as being beneficial in human health. He points out that, as with many environmental factors, we have evolved to live successfully in the presence of ionizing radiations. His own research suggests that radiation exposure can minimize infectious disease, reduce the incidence of cancer in the young, and substantially increase average lifespan.
     Studies on the growth, average lifespan, and decreased cancer mortality rates of humans exposed to low-dose irradiation show improved health, explains Luckey. This represents good evidence that we live with a partial radiation deficiency and that greater exposure to radiation would improve our health, a notion supported by 130 on the health of people living in parts of the world with higher background levels of ionizing radiation than average.

     Luckey suggests that the medical use of small samples of partially shielded radioactive waste would provide a simple solution to radiation deficiency. Of course, there are several questions that will have to be answered before a health program based on this study could be implemented. How much should we have and what is the optimum exposure?
     Evidence suggests that low dose exposure increases the number and activity of the immune system's white blood cells, boosts cytocrine and enzyme activity, and increases antibody production and so reduces the incidence of infection, assists in wound healing, and protects us from exposure to high doses of radiation.
     "It is unfortunate that most literature of radiobiology involves fear and regulations about the minimum possible exposure with no regard for radiation as a beneficial agent," says Luckey, "Those who believe the Linear No Threshold (LNT) dogma have no concept about any benefits from ionizing radiation. Many radiobiologists get paid to protect us from negligible amounts of ionizing radiation. Our major concern is health."
     Professor André Maïsseu, the journal's Editor-in-Chief, and President of the World Council of Nuclear Workers WONUC) says: "This is a very bright, interesting and important paper about the real effects of ionizing radiation - radioactivity - on humans, mammals and biotopes." He adds that, the paper, "is part of the movement we - nuclear workers - promoting good science and fighting obscurantism in this scientific field."
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http://www.inderscience.com/browse/index.php?journalCODE=ijlr
Title:
Abundant health from radioactive waste
Author:
T.D. Luckey 
Address:
1719 Brandon Woods, Dr. Lawrence, KS 66047, USA
Journal:
International Journal of Low Radiation 2008 - Vol. 5, No.1  pp. 71 - 82
Abstract:
     When beliefs are abandoned and evidence from only whole body exposures to mammals is considered, it becomes obvious that increased ionising radiation would provide abundant health. The best source for that increased exposure is radioactive waste. A radiation deficiency is seen in a variety of species, including rats and mice; the evidence for a radiation deficiency in humans is compelling. We live in a partial deficiency of an essential agent, ionising radiation. Health benefits from increased chronic exposure are briefly reviewed. Safe radiation supplementation with waste from nuclear reactors is examined.
Keywords:
cancer; growth; human health; lifespan; nuclear workers; radiation deficiency; radiation supplementation; radioactive sculptures; radioactive waste; radon; ionising radiation; low radiation; safe radiation; nuclear waste; radiation exposure.
DOI:
10.1504/IJLR.2008.018820 
Commentaire Gazette nucléaire:
     C'est l'hormésis qui reparaît... Ce personnage repart sur la Relation Linéaire sans seuil (LNT en anglais). Elle n'est sûrement pas juste pour les faibles doses en particulier de contamination interne mais en l'état elle est un compromis si on tient compte de la spécificité de la contamination interne. Et les études menées orientent plutôt vers un effet plus important pour des faibles doses en ingestion ou inhalation chronique parce que les phénomènes sont très différents de ceux se produisant aux fortes doses. La Gazette N°245/246 p.16 et p.09 tente de répondre à ces questions.
La réponse d'un médecin à l'article (dont le titre est un peu provocateur...)

     Il est bien connu que l'exposition à des doses très basses, ce qui stimule les défenses cellulaires (augmentation de la production des enzymes responsable de la réparation des lésions ADN etc.) , a un effet «protecteur» sur des expositions ultérieures.
     MAIS il se passe bien d'autres phénomènes aussi: même l'exposition la plus basse (UNSCEAR 2000 parle de «the traversal of a single ionizing track») peut provoquer des lésions «irréparables» et peut donc être à l'origine d'un cancer ou d'un effet génétique. Il y a également le "Bystander effect"/Gazette Nucléaire) en français et surtout The bystander effect (pdf Annales de l'Association belge de Radioprotection, 2009) où des cellules non directement touchées développent quand-même des lésions,...

     Aussi bien l'UNSCEAR que le BEIR - Committee of the National Academy of Sciences - confirment dans leurs dernières publications (et même dans celles à venir très prochainement) le maintien de l'approche correspondant à une application en radioprotection de l'hypothèse LNT (linéaire sans seuil). Non pas parce qu'ils ont vu la preuve scientifique de cette corrélation jusqu'aux doses les +basses, mais parce que, compte tenu de tous les éléments disponibles, cette approche leur semble la plus «défendable» à l'heure actuelle.