Radiocesium

The reality of radioactive contamination of the environment was brought home to the world by the Chernobyl accident, which occurred on 26th April 1986. Radioactive clouds were produced and blown on the wind over large parts of Europe and Asia (IAEA, 1986). 

The resultant surface contamination was highly heterogeneous, with variations of factors up to 1000 within kilometer distances 

Radiocesium is an excellent indicator for the behavior of inactive cesium in the biosphere because its radiation can be detected rather quickly, its passage through the compartments of biosystems can be studied much more easily than by direct estimation of the inactive cesium content. Thus, the behavior of radiocesium in ecosystems supplies much information relating to cesium transport in the atmosphere, soil, plants, and animals. 

Most cesium compounds are water-soluble, and this enables plants to absorb almost all radiocesium from the soil (Zhu and Smolders, 2000). The cesium isotopes are transported and stored in plants much in the way that potassium ions are stored, and this results in total radiocesium contamination of the plant tissues that in turn are eaten by animals (Zhu and Shaw, 

In animals, cesium is absorbed almost totally in the intestine, and then distributed through the whole body via the blood circulation. Based on their analogy to potassium, radiocesium isotopes mainly accumulate in muscle tissues (Whickers and Finder, 2002). By contrast, connective tissues contain much less radiocesium, and fatty tissues are virtually radiocesium-free. 

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Aquatic Life. After Chernobyl, the consumption of freshwater fishes by Europeans declined, fish license sales dropped by 25%, and the sale of fish from radiocesium-contaminated lakes was prohibited (Brittain et al. 1991). Many remedial measures have been attempted to reduce radiocesium loadings in fishes, but none have been effective to date (Hakanson and Andersson 1992). 

Radiocesium concentrations in muscle of fishes from the southern Baltic Sea increased 3 to 4 times after Chernobyl (Grzybowska 1989), and 134+137Cs and 106Ru in fishes from the Danube River increased by a factor of 5. However, these levels posed negligible risk to human consumers... 

After the Chernobyl accident, radiocesium isotopes were also elevated in trees and lichens bordering an alpine lake in Scandinavia and in lake sediments, invertebrates, and fishes (Table 32.18). Radiocesium levels in muscle of resident brown trout (Salmo trutta) remained elevated for at least 2 years (Brittain etal. 1991). People consuming food near this alpine lake derived about 90% of their effective dose equivalent from the consumption of freshwater fish, reindeer meat, and milk. The average effective dose equivalent of this group during the next 50 years is estimated at 6 to 9 mSv with a changed diet and 8 to 12 mSv without any dietary changes (Brittain et al. 1991). 

Caribou in northern Quebec contained up to 1129 Bq 137Cs/kg muscle FW in 1986/87, but only 10 to 15% of this amount originated from Chernobyl the remainder is attributed to fallout from earlier atmospheric nuclear tests (Crete et al. 1990). The maximum concentration of 137Cs in meat of caribou (Rangifer tarandus granti) from the Alaskan Porcupine herd after the Chernobyl accident did not exceed 232 Bq/kg FW, and this is substantially below the recommended level of 2260 Bq 137Cs/kg FW (Allaye-Chan et al. 1990). Radiocesium transfer in an Alaskan lichen-reindeer-wolf (Canis lupus) food chain has been estimated. If reindeer forage contained 100 Bq/kg DW in lichens and 5 Bq/kg DW in vascular plants, the maximum winter concentrations — at an effective half-life of 8.2 years in lichens and 2.0 years in vascular plants — were estimated at 20 Bq/kg FW in reindeer-caribou skeletal muscle and 24 Bq/kg FW in wolf muscle (Holleman et al. 1990). 

The accident at the Chernobyl, Ukraine, nuclear reactor on April 26, 1986, contaminated much of the northern hemisphere, especially Europe, by releasing large amounts of radiocesium-137 and other radionuclides into the environment. In the immediate vicinity of Chernobyl at least 30 people died, more than 115,000 others were evacuated, and the consumption of locally produced milk and other foods was banned because of radiocontamination. The most sensitive local ecosystems were the soil fauna and pine forest communities. Elsewhere, fallout from Chernobyl measurably contaminated freshwater, marine, and terrestrial ecosystems, including flesh and milk of domestic livestock. Reindeer (Rangifer tarandus) calves in Norway showed an increasing frequency of chromosomal aberrations that seemed to correlate with cesium-137 tissue concentrations tissue concentrations, in turn, were related to cesium-137 in lichens, an efficient absorber of airborne particles containing radiocesium and the main food source of reindeer during winter. A pattern similar to that of reindeer was documented in moose (Alces) in Scandinavia. 

Baeza, A., M. del Rio, C. Miro, A. Moreno, E. Navarro, J.M. Paniagua, and M.A. Peris. 1991. Radiocesium and radiostrontium levels in song-thrushes (Turdus philomelos) captured in two regions of Spain. Jour. Environ. Radioactiv. 13 13-23. 

Bagshaw, C. and I.L. Brisbin, Jr. 1984. Long-term declines in radiocesium of two sympatric snake populations. Jour. Appl. Ecol. 21 407-413. 

Brisbin, I.L., Jr. M.A. Staton, J.E. Pinder, III, and R.A. Geiger. 1974. Radiocesium concentrations of snakes from contaminated and non-contaminated habitats of the AEC Savannah River Plant. Copeia 1974 (2) 501-506. 

Brittain, J.E., A. Storruste, and E. Larsen. 1991. Radiocesium in brown trout (Salmo trutta) from a subalpine lake ecosystem after the Chernobyl reactor accident. Jour. Environ. Radioactivity 14 181-191. 

Colwell, S.V., R.A. Kennamer, and I.L. Brisbin, Jr. 1996. Radiocesium patterns in wood duck eggs and nesting females in a contaminated reservoir. Jour. Wildl. Manage. 60 186-194. 

Holleman, D.F., R.G. White, and A.C. Allaye-Chan. 1990. Modelling of radiocesium transfer in the lichen-reindeer/caribou-wolf food chain. Rangifer, Spec. Iss. No. 3 39-42. 

Hove, K., O. Pederson, T.H. Garmo, H.S. Hansen, and H. Staaland. 1990a. Fungi amajor source of radiocesium contamination of grazing ruminants in Norway. Health Phys. 59 189-192. 

Hove, K., H. Staaland, O. Pedersen, and H.D. Sletten. 1990b. Effect of Prussian blue (ammonium-iron-hexacyanoferrate) in reducing the accumulation of radiocesium in reindeer. Rangifer, Spec. Iss. No. 3 43. 

Imanaka, T. and H. Koide. 1990. Radiocesium concentration in milk after the Chernobyl accident in Japan. Jour. Radioanal. Nucl. Chem. 145 151-158. 

Johanson, K.J., G. Karlen, and J. Bertilsson. 1989. The transfer of radiocesium from pasture to milk. Sci. Total Environ. 85 73-80. 

Jones, B.E.V., O. Eriksson, and M. Nordkvist. 1989. Radiocesium uptake in reindeer on natural pasture. Sci. Total Environ. 85 207-212. 

Kalas, J.A., S. Bretten, I. Byrkjedal, and O. Njastad. 1994. Radiocesium (137Cs) from the Chernobyl reactor in Eurasian woodcock and earthworms in Norway. Jour. Wildl. Manage. 58 141-147. 

Palo, R.T., P. Nelin, T. Nylen, and G. Wickman. 1991. Radiocesium levels in Swedish moose in relation to deposition, diet, and age. Jour. Environ. Qual. 20 690-695. 

Sugg, D.W., R.K. Chesser, J.A. Brooks, and B.T. Grasman. 1995. The association of DNA damage to concentrations of mercury and radiocesium in largemouth bass. Environ. Toxicol. Chem. 14 661-668. 

Wrenn, M.E., J.W. Lentsch, M. Eisenbud, G.J. Lauer, and G.P. Howells. 1971. Radiocesium distribution in water, sediment, and biota in the Hudson River estuary from 1964 through 1970. Pages 334-343 in D.J. Nelson (ed.). Radionuclides in Ecosystems. Proceedings of the Third National Symposium on Radioecology. May 10-12, 1971, Oak Ridge, TN. Vol. 1. Available from Natl. Tech. Infor. Serv., Springfield, VA 22151. 

Bunzl, K., Schimmack, W., Belli, M., and Riccardi, M., 1997, Sequential extraction of fallout radiocesium from the soil Small scale and large-scale spatial variability. J. Radioanal. Nucl. Ghent. 226 47-53. 

Lasat, M.M., Fuhrmarm, M., Ebbs, S.D., Cornish, J.E., and Kochian, L.V., 1998, Phytoremediation of radiocesium-contaminated sod Evaluation of cesium-137 bioaccumulation in the shoots of three plant species. J. Environ. Qual. 27 165-169. 

Velasco, R. H., Toso, 1. P., Belli, M., and Sansone, U., 1997, Radiocesium in the northeastern part of Italy after the Chernobyl accident Vertical soil transport and soil-to-plant transfer. J. Environ. Radioac. 37 72- 2. 

Liu C, Zachara JM, Smith SC, McKinley JP, Ainsworth CC (2003) Desorption kinetics of radiocesium from subsurface sediments at Hanford Site USA. Geochim Cosmochim Acta 67 2893-2912 Loffredo E, Senesi N (2006) Eate of anthropogenic organic pollutants in soils with emphasis on adsorption/desorption processes of endocrine disruptor compounds. Pure App Chem 78 947-961... 

Ra, Sb, and Th (Joshi 1991). Radiocesium-137 in water from the Hudson River esmary. New York, decreased tenfold between 1964 and 1970, but the Cs content in fish and in sediments remained relatively constant (Wrenn et al. 1971). The effluent from the United Kingdom s Atomic Energy Agency SeUafield facility on the Cumberland Coast of the Irish Sea contained °Sr and Cs, which are soluble in seawater and tend to remain in solution, and Ru, and Zr/ Nb, which are relatively insoluble in seawater and coprecipitate or adsorb on free inorganic and organic surfaces (Pentreath etal. 1971). 

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