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PubMed2006

Management of spent sealed radioactive sources in Turkey.

Spent radioactive sources (SRS) have been generated from industrial applications, research, and medicine in Turkey. In this study, management of SRS (Co, Cs) at Cekmece Waste Processing and Storage Facility (CWPSF) is described. Eleven Cs sources (total 851 GBq) and four Co sources (total 27.75 GBq) that had been used as levels and density gauges were conditioned. Reinforced metal drums (200 L in volume) and cement matrix were used for conditioning of these sources. In this way, greater confinement was achieved for long-term storage. Maximum dose rates at the surface of the conditioned waste package were determined. In addition to information about conditioning stages of the sources, various calculations that have been done for shielding are presented. Surface dose rates of the waste packages were 1.60 mSv h for Cs and 1.63 mSv h for Co. Measurements of the final waste packages were presented to fulfill the requirements (<2 mSv h) of transportation according to regulations for the safe transport of radioactive material.

Cesium Radioisotopes↗
PubMed2006

Improving the regulation and management of low-activity radioactive wastes.

This paper summarizes the first phase of a study in progress by a committee of the National Research Council's Board on Radioactive Waste Management. The Board initiated the study after observing that statutes and regulations administered by the federal and state agencies that control low-activity radioactive wastes have developed as a patchwork over almost 60 y. These controls usually reflect the enterprise or process that produced the waste rather than the waste's radiological hazard. Inconsistencies in the regulatory patchwork or its application may have led to overly restrictive controls for some low-activity wastes while others were neglected in comparison. In the first phase of this study, the committee reviewed current low-activity waste inventories, regulations, and management practices. This led the committee to develop five categories that encompass the spectrum of low-activity wastes and serve to illustrate gaps and inconsistencies in current regulations and management practices. The committee completed its first phase with four findings that will lead into the final phase of the study. This paper is excerpted from the committee's interim report that was issued in October 2003.

Decision Making↗
PubMed2006

International standards related to the classification and deregulation of radioactive waste.

Although solid radioactive waste management is mainly a national concern, there are some aspects that have international implications. One important example is the decommissioning of nuclear facilities, which results in the release of materials that could be reused and recycled. It is possible that these materials could enter international trade, especially if the material is a metal. It is clearly desirable, therefore, to have appropriate international standards to help regulate trade. This paper describes recent international developments relating to the establishment of radiological criteria for the release of materials from regulatory control (clearance). There have already been some experiences of clearance and the transfer of recycled materials within Europe, and this paper reviews that experience. It also discusses recent developments in relation to the international classification of radioactive waste.

Decision Making↗
PubMed2001

Radioactive gold-198 seeds for the treatment of squamous cell carcinoma in the eyelid of a cat.

A 19-year-old, speyed, domestic short-hair cat was presented with an eyelid tumour of 3 months duration. Ophthalmic examination revealed a large, raised, ulcerated and bleeding mass affecting the left lower eyelid. The mass was 12 mm x 10 mm in size, extended to the medial canthus and had eroded 10 mm of eyelid margin. Mandibular lymph nodes were not palpably enlarged. A diagnosis of squamous cell carcinoma was confirmed by histologic examination. Due to involvement of more than half the lower eyelid, it was decided that treatment with radioactive gold-198 seeds was appropriate. Nine radioactive gold-198 seeds were implanted, delivering a minimum tumour dose of 65 Gy. Three weeks postoperatively the mass had resolved, with only a small scab remaining. After a further 3 weeks, there was no evidence of the eyelid tumour. Although approximately 7 mm of eyelid margin was absent, this did not cause any clinical signs other than mild conjunctivitis. There was no evidence of the tumour 10 months postoperatively, when the cat was euthanased for unrelated disease.

Animals↗
PubMed1980

Radioactive plume from the Three Mile Island accident: xenon-133 in air at a distance of 375 kilometers.

The transit of an air mass containing radioactive gas released from the Three Mile Island reactor was recorded in Albany, New York, by measuring xenon-133. These measurements provide an evaluation of Three Mile Island effluents to distances greater than 100 kilometers. Two independent techniques identified xenon-133 in ambient air at concentrations as high as 3900 picocuries per cubic meter. The local gamma-ray whole-body dose from the passing radioactivity amounted to 0.004 millirem, or 0.004 percent of the annual dose from natural sources.

Air Pollution, Radioactive↗
PubMed2003

Engineering Deinococcus geothermalis for bioremediation of high-temperature radioactive waste environments.

Deinococcus geothermalis is an extremely radiation-resistant thermophilic bacterium closely related to the mesophile Deinococcus radiodurans, which is being engineered for in situ bioremediation of radioactive wastes. We report that D. geothermalis is transformable with plasmids designed for D. radiodurans and have generated a Hg(II)-resistant D. geothermalis strain capable of reducing Hg(II) at elevated temperatures and in the presence of 50 Gy/h. Additionally, D. geothermalis is capable of reducing Fe(III)-nitrilotriacetic acid, U(VI), and Cr(VI). These characteristics support the prospective development of this thermophilic radiophile for bioremediation of radioactive mixed waste environments with temperatures as high as 55 degrees C.

Biodegradation, Environmental↗
PubMed1965

MEASUREMENT OF THE FALL IN THE LEVEL OF PLASMA RADIOACTIVITY AFTER INTRAVENOUS ADMINISTRATION OF RADIOHIPPURAN AS A TEST OF RENAL FUNCTION.

The level of plasma radioactivity following a single intravenous injection of (131)I-labelled sodium orthoiodohippurate (radiohuppuran) falls with time in a tri-exponential fashion. The rate of fall of plasma radioactivity after an intravenous injection of radiohippuran was measured over the period 25 to 40 minutes from the time of injection and was expressed as the half-life of radiohippuran. The results suggest that this procedure may provide a valid measure of renal function which is more sensitive than the blood urea estimation but less sensitive than the creatinine clearance.

Blood Chemical Analysis↗
PubMed2006

Results of EPR dosimetry for population in the vicinity of the most contaminating radioactive fallout trace after the first nuclear test in the Semipalatinsk test site.

The method of electron paramagnetic resonance (EPR) spectroscopy for tooth enamel is applied to individual radiation dose determination to residents of two villages (Dolon and Mostik) in the vicinity of the Semipalatinsk nuclear test site in Kazakhstan. These villages are located near the central axis of the radioactive fallout trace of the most contaminating surface nuclear test conducted in 1949. It is found that excess doses obtained by subtraction of natural background dose from dose absorbed in enamel range up to 440 mGy to residents of Dolon, whose enamel was formed before 1949, and do not exceed 120 mGy to younger residents. To residents of Mostik, excess doses do not exceed 100 mGy regardless of age except for one resident with an extremely high dose of 1.25 Gy. These results are in agreement with the pattern of radioactive contamination of the territory after the nuclear test of 1949 except one case of extremely high dose, which should be additionally investigated.

Adult↗
PubMed1998

Radioactive fucose as a tool for studying glycoprotein secretion.

The efficiency and reliability of radioactive fucose as a specific label for newly synthesized glycoproteins were investigated. Young adult male rabbits were injected intravitreally with [3H]-fucose, [3H]-galactose. [3H]-mannose, N-acetyl-[3H]-glucosamine or N-acetyl-[3H]-mannosamine, and killed 40 h after injection. In another series of experiments rabbits were injected with either [3H]-fucose or several tritiated amino acids and the specific activity of the vitreous proteins was determined. Vitreous samples were also processed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and histological sections of retina, ciliary body and lens (the eye components around the vitreous body) were processed for radioautography. The specific activity (counts per minute per microgram of protein) of the glycoproteins labeled with [3H]-fucose was always much higher than that of the proteins labeled with any of the other monosaccharides or any of the amino acids. There was a good correlation between the specific activity of the proteins labeled by any of the above precursors and the density of the vitreous protein bands detected by fluorography. This was also true for the silver grain density on the radioautographs of the histological sections of retina, ciliary body and lens. The contribution of radioautography (after [3H]-fucose administration) to the elucidation of the biogenesis of lysosomal and membrane glycoproteins and to the determination of the intracellular process of protein secretion was reviewed. Radioactive fucose is the precursor of choice for studying glycoprotein secretion because it is specific, efficient and practical for this purpose.

Animals↗
PubMed1979

[Study on decontamination of radioactive ruthenium by steel wool in waste solution (author's transl)].

Tracer experiments were done in order to establish a decontamination process of 106Ru in radioactive waste solution by column method paying special attention on the solution of nitratonitrosyl complex of Ru which is often encountered as a low level radioactive waste solution. It turned out that metallic iron was the most effective decontaminating agent among the several tens of materials tested. The decontamination factor (DF) of 106Ru increased in proportion to the total surface area of iron and it sensitively depended on the oxidation state of the surface as revealed by the batchwise and columnwise tests. Iron samples with high corrosiveness gave a much larger DF than those with low corrosiveness. The decontamination process proceeded as iron was being oxidized via Fe(metal)leads toFe(II)leads toFe(III). As the results, the DF initially increased after initiating the passage of water through the column but it then decreased as the oxidation process became inactive. An excellent durability up to 10000 bed volumes was demonstrated by the column method at a high average DF of 150.

Alloys↗
PubMed1988

[Management of radioactive wastes using a personal computer].

This paper describes a software package for a personal computer which deals with storage records of radioactive wastes; the software keeps the records of purchase and use of radioisotopes and makes the inventory records of radioactive wastes. The records for the cargo booking of the wastes for the Japanese Radioisotope Association can be prepared by this software package.

Microcomputers↗
PubMed1975

Treatment of persistent knee effusions with intra-articular radioactive gold.

Patients with a total of 112 chronic knee effusions unresponsive to the usual conservative methods of therapy were treated with intra-articular injections of radioactive gold and followed from 6 months to 5 years. Most patients in the study had rheumatoid arthritis but others had ankylosing spondylitis, psoriatic arthritis, intermittent hydrathrosis and undiagnosed synovitis. After 6 months 81% showed improvement. This figure diminished to approximately 70% at 1 and 2 years, 60% at 3 and 4 years and 50% at 5 years. The mose beneficial results were seen in patients with intermittent hydrarthrosis. Twelve patients with a synovial cyst and/or rupture improved. Patients with thin synovia and anatomic stage I or II disease did best, but those with stage III disease also did well. After the injection 33% of the patients had a reactive synovitis. A variable amount of radioactive material escaped from the knee to the regional lymph nodes and general circulation.

Age Factors↗
PubMed1975

The management of radioactive wastes resulting from emergency situations on land and sea.

The term 'emergency' applies to unplanned events that have generated, or had the potential to generate, radioactive wastes that could not be handled locally. Reports of past emergencies form the basis for discussion of future trends in emergency situations, the factors that influence waste management, the technology of waste management and personnel requirements. The number of past emergencies has been small and these have not increased the volume of radioactive wastes significantly. The majority of future emergencies are likely to be associated with reactors as they have been in the past. Little change in the nature of the waste is expected, although the greater use of separated plutonium may create some new problems. The factors that influence emergency waste management fall into two categories, those that are concerned with the location of the emergency event, and those concerned with the characteristics of the wastes. As in the past, it can be expected that in most emergencies proven waste management techniques will be adapted to suit the local circumstances but there is a need for simpler and more economic methods. Trained personnel and comprehensive planning are cited as key factors in successful waste management operations.

Accidents↗
PubMedDate not supplied

[Effect of combined radioactive and chemical (heavy metals, herbicides) pollution on the yield of cytogenetic disruptions in the intercalary meristem of spring barley].

The yield of aberrant cells and their loading with lesions of intercalary meristem of spring barley in conditions of the combined action of 137Cs, heavy metals and 2.4-D herbicide was studied. At simultaneous insertion of 137Cs and Cd into the soil, the type of non-linearity of the yield of aberrant cells was determined by radioactive pollution: in a range of low concentrations the synergistic effects took place, in a range of higher ones the antagonistic effects did. In the presence of cadmium, the severity of radiation induced damage to aberrant cells was significantly less. The interaction in 137Cs-Pb pair had an antagonistic character. The yield of aberrant cells was determined mainly by lead, whereas the radioactive pollution played the main role in loading of the aberrant cells with lesions. At the combined pollution with 137Cs and other contaminants, the antagonistic effects were more pronounced with Pb than with Cd, and further increased with the herbicide, both in the test on frequency of aberrant cells and the test on the loading of aberrant cells with lesions. In case of combination of the chemical agents the non-linear effects in test on loading of aberrant cells with lesions were mainly synergistic, whereas in the test on frequency of aberrant cells they were antagonistic. Only Pb-Cd pair and only in the test on loading of aberrant cells with lesions no significant non-linear effects were found. The results show high rate of the induction of synergistic and antagonistic effects in conditions of the combined action of low concentrations of the investigated agents on plants. These effects substantially determined the yield of cytogenetic disturbances in the studied range.

2,4-Dichlorophenoxyacetic Acid↗
PubMed1965

STUDIES OF INHIBITION OF INTESTINAL ABSORPTION OF RADIOACTIVE STRONTIUM. IV. ESTIMATION OF THE SUPPRESSANT EFFECT OF SODIUM ALGINATE.

A method is reported which permits selective suppression of absorption of radioactive strontium from ingested food material, allowing calcium to be available to the body. Studies were carried out on the inhibitory effect of various amounts of sodium alginate and the dose-response relationship of Sr(89) and bone uptake. The results obtained indicated that under laboratory conditions sodium alginate effectively reduces Sr(89) uptake in a constant proportion. This effect was observed at the three levels of administration of 1.4%, 12% and 24% of sodium alginate. The linear relationship between the dosage of the radioisotope and the bone uptake in the presence of sodium alginate suggests that the same proportion is maintained at the lower levels of intake of radioactive strontium.Previous studies with small constant doses of sodium alginate were extended in rats to a period corresponding approximately to three years of human life span. Low doses were sufficient to reduce appreciably bone uptake of radiostrontium.

Alginates↗
PubMedDate not supplied

[Variability of enzyme systems in the coenopopulation of Taraxacum officinale s.l. from the zone of East-Ural- radioactive trace].

Levels of soil contamination with 90Sr and 137Cs radionuclides on the plots within the zone of Eastern-Ural radioactive trace exceed values of the global level 4-240 times. We have carried out allozyme analysis of apomict species Taraxacum officinale s.l. from this zone. Zimogrammes were interpreted as allozyme phenotypes. In condition of chronic irradiation the plants had increased phenogenetic variability of majority enzymes systems and high frequency of rare morphs. Thus, in plant coenopopoulations situated in radioactive-polluted zone, genomic recombination processes show higher intensity. High enzymatic variability provides the material for natural selection and increase the adaptive potential of coenopopulations.

Russia↗
PubMed2006

[Hight-temperature matrices to immobilize radioactive waste].

To immobilize liquid radioactive waste with medium activity level, specialists of "RADON" Industrial Research Association use borosilicate glass incorporating up to 30-35 mass percent of radioactive waste, with sulfate and chloride ions content up to 1 mass percent. To increase those concentrations, the authors suggest putting phosphate or vanadate additives into borosilicate glass or using phosphate glass. In vitrification of solid waste, for instance burning oven slag, sodium silicate or dolomite and bentonite mixture are suggested as additives.

Bentonite↗