Les multiples et gigantesques incendies de forêt et de tourbe qui ravagent depuis plus de 10 jours la Russie remettent en suspension une partie des retombées de Tchernobyl, de Mayak et des essais nucléaires. La situation semble à ce jour particulièrement critique autour du site atomique de Mayak qui a subi en 1957 les retombées de plus de 20 millions de Curies (dont du Plutonium 239.... NB une dose létale par inhalation de Pu239 pèse officiellement 46 microgrammes) suite à une explosion qui a transformé une partie des environs forestiers en zone interdite aujourd’hui au demeurant en feu au point que l’état d’urgence a été décrété. Un nouveau nuage radioactif s’est déjà levé, nous le respirerons tous à un moment ou un autre, avec le temps nous subirons tous plus ou moins dramatiquement les conséquences sanitaires de cette contamination interne supplémentaire. S’il est pour l’heure actuelle impossible de préciser les quantités de nucléides soulevées dans la troposphère, on peut d’ores et déjà affirmer avec certitude que l’on est en présence d’une inéluctable catastrophe nucléaire pour les populations locales et le monde entier. Il n’est en effet pas un seul km2 du territoire occidental Russe qui n’ait été plus ou moins lourdement marqué par l’un où les deux de ces accidents nucléaires majeurs qui sont venus aggraver les retombées des essais atomiques. Dans ces nuages il y a désormais, des fines particules respirables de Strontium, de Césium, de différents isotopes d’Uranium et de Plutonium ainsi que du terrible Américium 241 tout droit venu de la décroissance du Plutonium 241. Le gouvernement Russe fait bien de décréter l’embargo de ses exportations agricoles contaminées. Pour notre part nous nous inclinons devant tous ces hommes qui là bas combattent ces feux d'inhumanité.
NB. Du plutonium et de l'américium resuspendu par les incendies qui ont atteint ces jours-ci le Colorado ont été récemment découvert dans l'air. Il faut dire qu'une partie de cette région des Etats-Unis, fameuse pour sa fabrique de plutonium non loin de Denver, n'est pas beaucoup mieux lotie que la zone Russe de Mayak. http://www.aolnews.com/nation/article/activists-say-plutonium-particles-found-in-air-near-rocky-flats/19581335
Les feux de tourbières risquent de persister des mois en Russie,
Selon le groupe Wetlands International, voué à la protection des zones humides, la fumée qui s'est répandue sur Moscou provenait à 80 ou 90% de feux de tourbières des environs de la capitale, et non des feux de forêt liés à ce que les autorités tiennent pour l'été russe le plus chaud depuis un millénaire.
http://www.lesechos.fr/info/inter/reuters_00273145-les-feux-de-tourbieres-risquent-de-persister-des-mois-en-russie.htm
This contamination site known now as East Urals Radioactive Trace (EURT). It covers about 15,000-20,000 km2 territory, with approximately 5% (about 1,000 km2) with initial radionuclide densities greater than 70 GBq/km2.
Abstract
The large-scale nuclear accident took place at the production association “Mayak” in the Southern Urals in 1957. About 74 PBq of radioactive substances were released into the atmosphere, which resulted in the contamination of a vast area – East-Ural radioactive trace (EURT). The results of our study have shown that the density of contamination of 90Sr and137Cs in the frontal part of the EURT are 6700–15000 and 200–400 kBq/m2, respectively. The total deposition for 90Sr within the East-Ural Radioactive State Reserve was 428.2 (286.4–643.4) TBq (NB --> 8,14 gr de Sr90, poids en gr d'une dose létale par inhalation de 5 Sievert selon les facteurs de doses officiels (1,5E-7 Sv/Bq) 6,6E-6 gr --> 12,8 millions de doses létales potentielles,), for 137Cs – 15.1 (10.2–22.4) TBq (NB --> 4,7 gr de Cs137, poids en gr d'une dose létale par inhalation de 5 Sievert selon les facteurs de doses officiels (4,8E-9 Sv/Bq) 3,24E-4 gr --> 14500 doses létales potentielles.), for 239,240Pu – 1.175 (0.623–2.242) TBq. (NB --> au moins 220 gr de Pu239, poids en gr d'une dose létale par inhalation de 5 Sievert selon les facteurs de doses officiels (4,7E-5 Sv/Bq) 4,6E-5 gr --> 4,7 millions doses létales potentielles & au moins également 71 gr de Pu240, poids en gr d'une dose létale par inhalation de 5 Sievert selon les facteurs de doses officiels (4,7E-5 Sv/Bq) 1,26E-5 gr --> 5,6 millions de doses létales potentielles )
The large-scale nuclear accident took place at the production association “Mayak” in the Southern Urals in 1957. About 74 PBq of radioactive substances were released into the atmosphere, which resulted in the contamination of a vast area – East-Ural radioactive trace (EURT). The results of our study have shown that the density of contamination of 90Sr and137Cs in the frontal part of the EURT are 6700–15000 and 200–400 kBq/m2, respectively. The total deposition for 90Sr within the East-Ural Radioactive State Reserve was 428.2 (286.4–643.4) TBq (NB --> 8,14 gr de Sr90, poids en gr d'une dose létale par inhalation de 5 Sievert selon les facteurs de doses officiels (1,5E-7 Sv/Bq) 6,6E-6 gr --> 12,8 millions de doses létales potentielles,), for 137Cs – 15.1 (10.2–22.4) TBq (NB --> 4,7 gr de Cs137, poids en gr d'une dose létale par inhalation de 5 Sievert selon les facteurs de doses officiels (4,8E-9 Sv/Bq) 3,24E-4 gr --> 14500 doses létales potentielles.), for 239,240Pu – 1.175 (0.623–2.242) TBq. (NB --> au moins 220 gr de Pu239, poids en gr d'une dose létale par inhalation de 5 Sievert selon les facteurs de doses officiels (4,7E-5 Sv/Bq) 4,6E-5 gr --> 4,7 millions doses létales potentielles & au moins également 71 gr de Pu240, poids en gr d'une dose létale par inhalation de 5 Sievert selon les facteurs de doses officiels (4,7E-5 Sv/Bq) 1,26E-5 gr --> 5,6 millions de doses létales potentielles )
Kyshtym is near the Chelyabinsk-40 nuclear complex, also known as "Mayak" ("lighthouse" in Russian), where on 29 September, 1957, a violent explosion involving dry nitrate and acetate salts in a waste tank containing highly radioactive waste, contaminated an area of more than 15,000 square kilometres (Ozyorsk was the town built around the Mayak combine, but it was a closed city, which was not marked on maps, thus making Kyshtym the nearest town to the location of the disaster). The explosion resulted from a failure of the cooling system of the tank.
There was a release of 740 PBq of fission products, approximately 10% of which was dispersed into the atmosphere. Cerium-144 and Zirconium-95 (both relatively short lived isotopes with a half life of 285 and 64 days respectively) made up 91% of the release. There was 1 PBq of Sr-90, and 13 TBq of Cs-137. The contaminated zone, called East Urals Radioactive Trace (EURT), measuring 300 x 50 km was contaminated by more than 4 kBq/m² of Sr-90. The global fallout of Sr-90 was about 2 kBq/m². An area measuring 17 km² was contaminated by about 100 MBq Sr-90/m².
The Kyshtym accident was largely concealed by the Soviet government until 1980, when the Soviet biologist Zhores Medvedev revealed its existence.
Voir aussi notamment pour les cartes la United States Nuclear Regulatory Commission . http://www.posse.net/dicus/s-97-04.htm
En Français voir: http://resosol.org/InfoNuc/criticiteMayak.htm
L'accident nucléaire de Kyshtym est le plus grave de tous ceux qui sont survenus dans l'ex-Union soviétique; ses conséquences sont, à ce jour, les plus importantes au monde. En réalité, il faut le replacer dans l'ensemble des accidents et des dispersions de radioactivité qui se sont produits dans cette région industrialisée de l'Oural - le complexe Mayak - située entre Ekaterinbourg (ex-Sverdlovsk) et Tcheliabinsk.
Cet accident est resté secret pendant plus de trente ans. Une surface de 120 kilomètres carrés était le siège d'une activité 90Sr supérieure à 100 Ci/km2 (3,7 millions de Bq/m2) avec à l'intérieur une zone de 5 kilomètres carrés où l'activité dépassait 2.000 Ci/km2, (74 millions de Bq/m2). Les Soviétiques ont décidé d'évacuer une zone de 1.000 kilomètres carrés où vivaient dix mille habitants et où régnait une activité égale ou supérieure à 2 Ci/km2 de 90Sr au sol (74.000 Bq/m2)
Contamination interne par le plutonium des habitants de la zone.
Contamination interne par le plutonium des habitants de la zone.
Plutonium and uranium in human bones from areas surrounding the Semipalatinsk nuclear test site. Yamamoto M, Hoshi M, Sakaguchi A, Shinohara K, Kurihara O, Apsalikov KN, Gusev BI. J Radiat Res (Tokyo). 2006.
Transport of Radioactive Materials by Wildland fires in the Chernobyl Accident Zone In the Bryansk Region the area of radioactive fires made up 200 ha. As a result of radionuclide transfer with fire smokes tohundreds of kilometers the content of Cs-137 in the atmosphere increased on the all territory of Russia contaminated by radionuclides. A very high increase took place in May and August during fire peaks (Dusha-Gudym 1996, 1999).
Dusha-Gudym, S.I. 1996. The effects of forest fires on the concentration and transport of radionuclides. In J.G. Goldammer & V.V. Furyaev, eds. Fire in ecosystems of boreal Eurasia, p. 476-480. Dordrecht, the Netherlands, Kluwer Academic Publishers.
"The analysis of radionuclids in four filters most affected by 137 Cs contamination revealed that smoke aerosol contained beta- and alpha-emitting 90Sr (strontium-90) and 239 Pu (plutonium-239)."
P.477
http://books.google.it/books?id=r-OMjt9DqHwC&pg=PR8&dq=Dusha-Gudym+The+effects+of+forest+fires+on+the+concentration+and+transport+of+radionuclides.&hl=it&ei=aQpqTN3NNYGiOOqJqboM&sa=X&oi=book_result&ct=result&resnum=4&ved=0CD8Q6AEwAw#v=onepage&q=Dusha-Gudym%20The%20effects%20of%20forest%20fires%20on%20the%20concentration%20and%20transport%20of%20radionuclides.&f=false
Fire prevention in radiation contaminated forests
Amiro, B.D., Sheppard, S.C., Johnston, F.L., Evenden, W.G., Harris, D.R., 1996. Burning
radionuclide question: what happens to iodine, cesium and chlorine in biomass
fires? Sci. Total Environ. 187, 93-103.
Fogh, C.L., Roed, J., Andersson, K.J., 1999. Radionuclide resuspension and mixed
deposition at different heights. J. Environ. Radioactiv. 46, 67-75.
Wotawa, G., De Geer, L.-E., Becker, A., D’Amours, R., Jean, M., Servranckx, R., Ungar, K.,
2006. Inter- and intra-continental transport of radioactive cesium released by
boreal forest fires. Geophys. Res. Lett. 33.
Torba radioattiva
I giganteschi incendi boschivi e di torbiera che imperversano in Russia da più di 10 giorni provocano la risospensione di parte delle ricadute radioattive di Chernobyl, di Myak e dei test nucleari. La situazione appare particolarmente critica intorno al sito nucleare di Myak dove nel 1957 a seguito di una esplosione si sono riversati nei dintorni oltre 20 milioni di Curie (tra cui anche plutonio 239....) trasformando parte delle foreste circostanti in zona di esclusione. A seguito degli incendi nell’area di Majak lo stato di emergenza è stato dichiarato. Una nuova nuvola radioattiva si è in breve già innalzata, la respireremo tutti noi prima o poi. Nel corso del tempo tutti noi soffriremo più o meno drammaticamente le conseguenze sanitarie di questa inevitabile contaminazione interna. Se è per ora impossibile precisare le quantità di nuclidi sollevatosi nella troposfera, possiamo già dire con certezza che si tratta di una ineluttabile catastrofe nucleare per le popolazioni locali e per il mondo intero. Non vi è infatti un solo km2 di territorio occidentale della Russia che non sia stato più o meno pesantemente segnato da uno o entrambi di questi due gravissimi incidenti nucleari che hanno sovrapposto la loro contaminazione a quella ereditata dalle prove atomiche. In queste nubi vi sono particelle fini respirabili di stronzio, cesio, di diversi isotopi di uranio e di plutonio nonché del terribile americio 241 proveniente dal decadimento del plutonio 241. Il governo russo ha ragione nel decretare l’embargo delle esportazioni dei prodotti agricoli contaminati. Da parte nostra ci inchiniamo davanti a questi uomini che combattono là questi fuochi d'inumanità.
This contamination site known now as East Urals Radioactive Trace (EURT). It covers about 15,000-20,000 km2 territory, with approximately 5% (about 1,000 km2) with initial radionuclide densities greater than 70 GBq/km2.
http://www.physics.harvard.edu/~wilson/publications/pp747/techa_cor.htm
Abstract
The large-scale nuclear accident took place at the production association “Mayak” in the Southern Urals in 1957. About 74 PBq of radioactive substances were released into the atmosphere, which resulted in the contamination of a vast area – East-Ural radioactive trace (EURT). The results of our study have shown that the density of contamination of 90Sr and137Cs in the frontal part of the EURT are 6700–15000 and 200–400 kBq/m2, respectively. The total deposition for 90Sr within the East-Ural Radioactive State Reserve was 428.2 (286.4–643.4) TBq (NB --> 8,14 gr di Sr90, peso in gr di una dose letale per inalazione di 5 Sievert secondo i fattori di dose ufficiali (1,5E-7 Sv/Bq) 6,6E-6 gr --> 12,8 milioni di dosi letali potenziali,), for 137Cs – 15.1 (10.2–22.4) TBq (NB --> 4,7 gr di Cs137, peso in gr di una dose letale per inalazione di 5 Sievert secondo i fattori di dose ufficiali (4,8E-9 Sv/Bq) 3,24E-4 gr --> 14500 dosi letali potenziali) , for 239,240Pu – 1.175 (0.623–2.242) TBq. (NB --> almeno 220 gr di Pu239, peso in gr di una dose letale per inalazione di 5 Sievert secondo i fattori di dose ufficiali (4,7E-5 Sv/Bq) 4,6E-5 gr --> 4,7 milioni di dosi letali potenziali, & almeno ugualmente 71 gr di Pu240, peso in gr di una dose letale per inalazione di 5 Sievert secondo i fattori di dose ufficiali (4,7E-5 Sv/Bq) 1,26E-5 gr --> 5,6 milioni di dosi letali potenziali.)
http://www.radioprotection.org/index.php?option=com_article&access=standard&Itemid=129&url=/articles/radiopro/abs/2009/05/radiopro44136/radiopro44136.html
Kyshtym is near the Chelyabinsk-40 nuclear complex, also known as "Mayak" ("lighthouse" in Russian), where on 29 September, 1957, a violent explosion involving dry nitrate and acetate salts in a waste tank containing highly radioactive waste, contaminated an area of more than 15,000 square kilometres (Ozyorsk was the town built around the Mayak combine, but it was a closed city, which was not marked on maps, thus making Kyshtym the nearest town to the location of the disaster). The explosion resulted from a failure of the cooling system of the tank.
There was a release of 740 PBq of fission products, approximately 10% of which was dispersed into the atmosphere. Cerium-144 and Zirconium-95 (both relatively short lived isotopes with a half life of 285 and 64 days respectively) made up 91% of the release. There was 1 PBq of Sr-90, and 13 TBq of Cs-137. The contaminated zone, called East Urals Radioactive Trace (EURT), measuring 300 x 50 km was contaminated by more than 4 kBq/m² of Sr-90. The global fallout of Sr-90 was about 2 kBq/m². An area measuring 17 km² was contaminated by about 100 MBq Sr-90/m².
The Kyshtym accident was largely concealed by the Soviet government until 1980, when the Soviet biologist Zhores Medvedev revealed its existence.
http://en.wikipedia.org/wiki/Kyshtym
Vedere anche per mappe la United States Nuclear Regulatory Commission . http://www.posse.net/dicus/s-97-04.htm
In Italiano vedere: http://www.dmsa.unipd.it/~mazzia/lavori/seminario.pdf
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