Radionuclidic contamination

The complex interactions amongst geological, biological, and geochemical processes at the land-sea margin control the delivery and fate of radionuclides, contaminants, and other natural elements in coastal environments (Swarzenski et al. 2003). For many such constituents, there is at least a fundamental understanding of major source and sink functions and their potential estuarine transformation reactions. For example, rivers can be monitored quite easily for discharge rates into estuaries as well as for elemental... 

Bennett K, Biggs J, Fresquez P. 1996. Radionuclide contaminant analysis of small mammals, plants and sediments within Mortandad Canyon, 1994. Los Alamos, NM Los Alamos National Laboratory. LA-13104-MS UC-908 UC-902 contract no. W-7504-ENG-36 DE-96-007-463. 

Lee SY, Tamura T, Larsen IL, et al. 1987. Characteristics of radionuclide-contaminated soils from the Sedan crater area at the Nevada test site. Soil Sci 144(2) 113 -121. 

ToranL. 1994. Radionuclide contamination in groundwater Is there a problem In Environmental science pollution control series. New York, NY M. Dekker, 437-455. 

Radiation causes dominant lethal mutations in the medaka (Oryzias latipes) (Shima and Shimada 1991). Mosquitofish (Gambusia spp.) from radionuclide-contaminated ponds in South Carolina differed from conspecifics in reference ponds, as judged by the frequency of DNA markers, and this is consistent with the hypothesis that these DNA markers may originate from genetic elements that provide a selective advantage in contaminated habitats (Theodorakis et al. 1998). Ionizing radiation at low-level chronic exposure reportedly has no deleterious genetic effects on aquatic populations because exposure is compensated by density-dependent responses in fecundity (IAEA 1976). However, this needs verification. 

Theodrakis, C.W., J.W. Bickham, T. Elbl, L.R. Shugart, and R.K. Chesser. 1998. Genetics of radionuclide-contaminated mosquitofish populations and homology between Gambusia affinis and G. holbrooki. Environ. Toxicol. Chem. 17 1992-1998. 

Barnes, M. G. "Statistical Design and Analysis in the Cleanup of Environmental Radionuclide Contamination" Desert Research Institute, University of Nevada Las Vegas, NV, 1978 ... 

TABLE 1 Costs (in Dollars) Associated with Colloid-Polishing Filter Method TVeatment of Radionuclide-Contaminated Groundwater"... 

Removing radionuclide contamination from water using sunflowers was estimated to cost between 2 to 6 per 1000 gal of water treated. These costs include waste disposal and capital expenses (D131431). 

Isotopic methods to distinguish between radionuclide contamination from different sources... 

The Sr-82 used in these studies was produced by spallation of a molybdenum target with 800 MeV protons at the Los Alamos Meson Physics Facility (LAMPF) and radiochemically separated by the Nuclear Chemistry Group at Los Alamos Scientific Laboratory (LASL) (22). The major radionuclidic contaminant in the Sr-82 is Sr-85 which is present in at least 1 1 ratio relative to Sr-82. The actual ratio depends upon the length of time after the production of radioactive strontium. Because of the 65 day half life of Sr-85 and the 25 day half life of Sr-82, the Sr-85 Sr-82 ratio increases with time. Other radionuclides found by the Hammersmith group in the processed Sr-82/85 shipment were Sr-89 ( 1%), Sr-90 ( 0.01%), Co-58 ( 1%) and Rb-84 ( 1%) from (17). 

No radionuclidic contaminants of other elements have been observed in the shipped material. Of course, Sr-85 is always present and Sr-83 is present at short intervals after the irradiation. The presence of Sr-83 in the product leads to the formation of Rb-83 in the eluant from the generator. Large quantities of Sr-85 cause problems in shielding the generator. Inspection of the production data allows one to make the following characterizations of the strontium product a) for short irradiations ( 200 hours), the 82/85 ratio at EOB averages approximately 1.4 and the... 

Table 7-11. Effect of washing on radionuclide contamination (Bq g dry weight SEM) of spring wheat growing on a clay soil (Grogan, 1984).

Roh Y, Lee SY, Elless MP, Cho KS. Electro-enhanced remediation of radionuclide-contaminated groundwater using zero-valent iron (A35, pg. 1043, 2000). J Environ Sci Health, Part A 2000 35 1995. 

Other radionuclide-contaminated waste, generally called low-level waste, as generated in the reactor and fuel cycle, as well as in the radionuclide applications. (See Tables 21.14 and 21.15.)... 

Natural radionuclides contaminate air, food, and water. The annual per capita intake of natural radionuclides has been estimated to range from 2 Becquerels (Bq) for 232Th to about 130 Bq for 4 K (Sinclair 1988). The Bq is the International System of Units (SI) unit of radioactivity 1 Bq = 1 radioactive disintegration per second. The previously used unit of radioactivity is the Curie (Ci) 1 Ci = 3.7 x 1010 disintegrations per second, and 1 Bq = 27 x 10-12 Ci. The quantity of radiation or energy absorbed is expressed in Sievert (Sv), which is the SI unit of dose equivalent. The absorbed dose (in Gy) is multiplied by a quality factor for the particular type of radiation. Rem is the previously used unit for dose equivalent 100 rem = 1 Sv. 

The integral activity of SFAs makes up 2.5xl0 Bq (680 000 Ci). High gamma dose rates are recorded in rooms of SFA storage and in the adjacent rooms wherein surface radionuclide contamination varies within (0.25-8.33)xl0 Bq/m or (1.5-50)x 10 decay/min-cm. ... 

In the course of TSF rimning shielding barriers of some storage facilities degraded and partly lost their functions. As a result, radionuclides contaminated soils, aquatic systems, buildings and constructions generating thereby secondary sources of radioactive contamination requiring localization and elimination. 

RL Center Beltsville, MD cleanup of radionuclide contaminated sites Agriculture, Agricultural Research Service... 

APPLICATIONS DEALING WITH RADIONUCLIDE CONTAMINATION IN THE ENVIRONMENT... 

Applications Dealing with Radionuclide Contamination in the Environment... 

For strongly sorbing radionuclides, contaminant plumes will move very slowly and likely pose no potential hazards to current populations (Brady et ai, 2002). However, regulations may require cleanup of sites to protect present and future populations under a variety of future-use scenarios. In these cases, it may be necessary to use soil-flushing techniques to mobilize the radionuclides and then to collect them. Alternatively, it may be possible to demonstrate that contaminant... 

Adriano, D. C., Albright, J., Whicker, F. W., and Iskandar, I. K. (1997). Remediation of metal- and radionuclide-contaminated soil. In Remediation of Metal-Contaminated Soils, ed. Iskandar, I. K., and Adriano, D. C., Science Reviews, Northwood, Middlesex, England, 27-45. 

Unidentified Idaho Operations Office (USDOE) University of Toronto Microbial mineral transformations at the Fe(ll)/Fe(lll) redox boundary for solid Phase capture of strontium and other metal/radionuclide contaminants USDOE Environmental Management... 

Theodorakis CW and Shugart LR, Genetic ecotoxicology II Population genetic structure in radionuclide-contaminated mosquitofish (Gambusia affinis), Ecotoxicology, 6, 335, 1997. 

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