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PubMed1999

Collective dose estimates by the marine food pathway from liquid radioactive wastes dumped in the Sea of Japan.

IAEA-MEL has been engaged in an assessment programme related to radioactive waste dumping by the former USSR and other countries in the western North Pacific Ocean and its marginal seas. This paper focuses on the Sea of Japan and on estimation of collective doses from liquid radioactive wastes. The results from the Japanese-Korean-Russian joint expeditions are summarized, and collective doses for the Japanese population by the marine food pathway are estimated from liquid radioactive wastes dumped in the Sea of Japan and compared with those from global fallout and natural radionuclides. The collective effective dose equivalents by the annual intake of marine products caught in each year show a maximum a few years after the disposals. The total dose from all radionuclides reaches a maximum of 0.8 man Sv in 1990. Approximately 90% of the dose derives from 137Cs, most of which is due to consumption of fish. The total dose from liquid radioactive wastes is approximately 5% of that from global fallout, the contribution of which is below 0.1% of that of natural 210Po.

Animals↗
PubMed1977

Migration of radioactive products through alimentary chains (a review).

Data on the mobility of radioactive products in biocoenoses are presented and the main routes of their migration are discussed. Data on radioactive contamination of food products of vegetable, animal and marine origin are mentioned. It has been demonstrated that technological processing of raw material and culinary preparation of food products results in a considerable reduction in their contamination. Data on the amounts of radioactive nuclides taken up by the human organism in consequence of local and global fallout of radioactive products are reported.

Animals↗
PubMed2006

Ex vivo radioactive counts and decay rates of tissues resected during radioguided parathyroidectomy.

BACKGROUND: Radioguided parathyroidectomy using TC-99m-sestamibi injection and the handheld gamma probe allows more precise and rapid intraoperative localization of abnormal parathyroid glands. This technique is based on the principle that hypercellular parathyroid tissues have markedly higher in vivo radiotracer counts than surrounding tissue including thyroid and lymph nodes. While in vivo radioactivity after TC-99m-sestamibi administration in various tissues has been documented, there is a lack of data regarding ex vivo radioactive properties after surgical resection. METHODS: During a 6-week period in June/July 2005, 21 patients underwent radioguided parathyroidectomy by a single surgeon. Fifty-four tissue samples (39 parathyroid, 15 nonparathyroid) from these patients were collected and analyzed for ex vivo radioactive counts over a 30-min period. These data were then compared with the pathologic results. RESULTS: There is a significant difference in ex vivo counts between parathyroid adenomas, hyperplastic glands, and nonparathyroid tissue immediately after resection. However, radioactive decay/slope rates do not differ between the tissues. Importantly, an ex vivo count of >20% of background is 100% specific for parathyroid tissue. These differences persisted for up to 30 min. CONCLUSIONS: This is the first comprehensive study of ex vivo radioactive properties after TC-99m-sestamibi injection during radioguided parathyroidectomy. Parathyroids have a greater rate of uptake compared to nonparathyroid tissue, allowing ex vivo counts to predict tissue type. These tissues have similar decay rates, allowing these predictions to be made anytime up to 30 min after gland resection.

Adenoma↗
PubMed2002

Radioactive impact in sediments from an estuarine system affected by industrial wastes releases.

A big fertilizer industrial complex and a vast extension of phosphogypsum piles (12 km2), sited in the estuary formed by the Odiel and Tinto river mouths (southwest of Spain), are producing an unambiguous radioactive impact in their surrounding aquatic environment through radionuclides from the U-series. The levels and distribution of radionuclides in sediments from this estuarine system have been determined. The analyses of radionuclide concentrations and activity ratios have provided us with an interesting information to evaluate the extension, degree and routes of the radioactive impact, as well as for the knowledge of the different pathways followed for the radioactive contamination to disturb this natural system. The obtained results indicate that the main pathway of radioactive contamination of the estuary is through the dissolution in its waters of the radionuclides released by the industrial activities and their later fixation on the particulate materials. Tidal activity also plays an important role in the transport and homogenization along the estuary of the radioactivity released from the fertilizer plants.

Ecosystem↗
PubMed2004

Experience with airborne detection of radioactive pollution (ENMOS, IRIS).

This paper discusses the advantages of airborne monitoring of radioactive pollution and shows example maps indicating manmade pollution from different sources. The sensitivity of airborne radioactive detection is discussed. Comparisons of airborne and different ground measurements are presented. New instrumentation for airborne or ground moving vehicles is briefly described. Airborne footprinting provides rapid, well-defined spatial images of natural and manmade radioactive contamination. Data acquisition integrated with GPS navigation provides consistent data and guarantees proper data location. Real-time airborne measurements are re-calculated, with the use of special algorithms, into absolute units for individual radioactive nuclei contamination of the ground together with dose calculation. Raw records and calculated data are provided after enhanced post-flight processing. Dose rates and detection of different radioactive elements are presented. (ENMOS is a product of Picodas Group Inc. and IRIS is the product of Pico Envirotec Inc.)

Air Pollutants, Radioactive↗
PubMed2002

Nondestructive decontamination of mortar and concrete by electro-kinetic methods: application to the extraction of radioactive heavy metals.

Because the service lives of nuclear power plants are limited to a certain number of years, the need for the management of quite a large volume of radioactive contaminated concrete arises, which, in most cases, was not taken into account when the capacities of the low and medium activity repositories were designed. Therefore, the decontamination of these structures would be of great interest in order to declassify the wastes as radioactive and manage them as conventional ones. This research studies the reliability of the application of electrical fields to decontaminate radioactive contaminated concrete. Three series of decontamination experiments have been carried out, using Cs+, Sr2-, Co2+, and Fe3+ ions added during casting and that have penetrated from the outside, testing carbonated and uncarbonated matrixes, and using laboratory devices as well as the homemade device for in situ application named "honeycomb device". As a result, the application of electrical fields to concrete-contaminated structures has been developed as a new technique to extract radioactive ionic species from concrete. This method of decontamination has been patented by ENRESA (Spanish Company for the Management of Radioactive Wastes) in association with the IETcc.

Electricity↗
PubMed1990

[Comparative studies on the radioactivity of bone cements containing x-ray contrast media and of the contrast media].

Various PMMA bone cements containing zirconium oxide (ZrO2) as an X-ray contrast medium and zirconium oxides of several manufacturers were tested for their radioactivity by means of a gamma spectrometer. All the bone cements tested (Implast, Palacos R, and Sulfix-6) showed a certain degree of radioactivity. The radiation source in the bone cement is the added zirconium oxide, which is polluted by radioactive elements. The examination of various zirconium oxides showed some high radioactive emissions. The risk of radiation-induced cancer seems to be small, because the cements are normally implanted in humans older than 60 years. In view of the fact that these X-ray contrast media remain in the body for decades as components of the bone cement, the radioactive zirconium oxides should be replaced by high-purity radiation-free zirconium oxide or barium sulphate as soon as possible.

Bone Cements↗
PubMed1995

Biodegradation of radioactive animals.

The two most common disposal alternatives for animals contaminated with radioactive materials are incineration and burial. For most of the country burial has entailed shipping the carcasses to a commercial disposal facility at Barnwell, South Carolina, where it was landfilled along with other solid radioactive waste. Unfortunately, since 30 June 1994, this facility accepts waste generated by the states of the Southeast Compact only. Therefore, burial is no longer an option for most of the country's generators and incineration is an option only for those institutions which have, or have access to, an incinerator that is permitted to burn radioactive materials and that accepts animal carcasses with de minimis levels of radioactive contaminants. Many institutions, especially those in congested urban areas where the public does not support incineration, do not have viable outlets for radioactive animal carcasses. Interim, on-site storage poses problems of its own. Biodegradation of animal carcasses with dermestid beetles is an inexpensive approach to this waste management problem.

Animals↗
PubMed1999

Protocols for implementing DOE authorized release of radioactive scrap metals.

A process to implement the U.S. Department of Energy's (DOE) policy for authorized release of radioactive materials from DOE facilities is provided in the Draft Handbook for Controlling Release for Reuse or Recycle of Property Containing Residual Radioactive Material, published by DOE in 1997 and distributed to DOE field offices for interim use and implementation. The authorized release of such property is intended to permit its beneficial use across the entire DOE complex. A computerized management tool--P2Pro(RSM)--has been developed to aid in carrying out the release process for radioactive metals. It contains protocols for the authorized release process and relevant information to facilitate the evaluation of scrap metals for reuse and recycle. The P2Pro(RSM) protocols provide DOE and its contractors with an effective, user-friendly tool for managing authorized release activities P2Pro(RSM) is designed to be used in the Windows environment. The protocols incorporate a relational database coupled with a graphic-user interface to guide the user through the appropriate steps so authorized release limits can be developed. With the information provided in the database, an as-low-as-reasonably-achievable (ALARA) optimization process can be easily set up and run for up to 10 alternatives for disposition of radioactive scrap metals. The results of the ALARA optimization process can be printed in a series of reports and submitted as part of the application for the authorized release of the radioactive scrap metals.

Documentation↗
PubMed2000

Experimental incineration of low level radioactive samples.

To determine the volume reduction potential for incineration of radioactivity in low-level radioactive waste, an incineration experiment was performed at the Okayama University Radioisotope Center (OURIC). Solid low-level radioactive samples (LLRS) were prepared for 15 routinely used radionuclides (45Ca, 1251, 32p, 33p, 35S, 59Fe, 123I, 131I, 67Ga, 99mTc, 111In, 3H, 14C, 51Cr, and 201Tl). For each radionuclide, incinerated one at a time, the smoke duct radioisotope concentration was less than 1/10 of the regulatory concentration limit (The Japanese law concerning prevention of radiation hazard due to radioisotopes, etc.). The radionuclide-containing combustible and semi-combustible LLRS were incinerated at the AP-1 50R furnace erected at OURIC, and the distribution of radioactivity inside and outside the furnace was measured. In the experimental incineration of LLRS containing these 15 radionuclides, the fractions released (RF) in the gas phase of the final smoke duct ranged from 0.165 to 0.99. The radioactivities remaining in the incineration residue were 99mTc, 87%; 59Fe, 83.1%; 45Ca, 75%; 51Cr, 62.1%; 33P, 62.0%; 32P, 61.1%; 67Ga, 57.7%; 35S, 26.0%; 111In, 21.1%; 201Tl, 16.6%; 123I, 11.9%; 131I, 8.2%; 125I, 2.4%; 14C, 0.39%; 3H, 0.04%. In the incineration of LLR S containing 35S, the rate of adhesion to the furnace wall was lower at high-temperature (809 degrees C) incineration than at low-temperature (376 degrees C) incineration. For LLRS containing one of the three radioiodines, 123I, 125I, or 131I, no such difference was observed between low (372 degrees C) and high (827 degrees C) temperature incineration (RF varied from 0.82 to 0.94).

Incineration↗
PubMed2002

Radioactive waste minimization at a large academic medical facility.

The University of Texas Medical Branch (UTMB) at Galveston is a large academic medical center with about 12,700 employees, 350 radioisotope research labs and 200 permitted radioactive materials users. Consequently, UTMB generates a fairly large amount of radioactive waste. The majority of this waste contains short-lived radionuclides, such as 32P, 33P, and 35S, which are held for decay and then disposed at a sanitary landfill. However, some waste, including long-lived waste and stock vials, is compacted into drums and stored in a warehouse facility, on-site, until disposal at a low-level radioactive waste (LLRW) facility. Space in the warehouse is limited but disposal is currently cost prohibitive. A reevaluation of our program was conducted to see if volumes of LLRW requiring disposal at a commercial LLRW facility could be reduced. A reevaluation of the waste streams resulted in the shifting of most of the material that was being drummed for shipment to a LLRW facility to disposal by landfill or incineration. Materials that were previously assumed to be radioactive are now being evaluated prior to disposal to determine if they may be disposed of as non-radioactive waste. Following the initial evaluation, the amount of compacted dry solids assumed to contain long-lived radionuclides was reduced. The space that was saved due to the decrease in drumming for disposal is now used to hold the increased volume of decay-in-storage material. The monetary savings will amount to about $45,000 per year. This program is currently being expanded to reduce other waste streams at the university.

Academic Medical Centers↗
PubMed2006

Managing the disposition of potentially radioactive scrap metal.

In 2002, the National Council on Radiation Protection and Measurements (NCRP) issued Report No. 141, Managing Potentially Radioactive Scrap Metal. The report evaluates management policy and related issues regarding scrap metal generated in regulated facilities that have been under radiological control or have radiological concerns. It has been estimated that more than 9 million metric tons of scrap metal of all types that have been associated with the production or use of radioactive materials will be generated during the coming decades at various facilities across the United States. Currently, disposition of such metal has encountered particular obstacles, primarily because of the lack of a consistent disposition policy, systematic regulatory provisions, and, above all, public understanding. Without clarity in the regulatory passage, much of the scrap metal, including metal that has not been contaminated, could be mischaracterized as low-level radioactive waste, resulting in a costly disposition operation. NCRP Report No. 141 identifies this general category of metal as "potentially radioactive scrap metal" (PRSM) and discusses the viable disposition options for facilitating its management. Because much of the PRSM has been found to contain very low residual radioactivity or even none at all, one consideration is to release such metal outside of the radiological control framework. This would require the development and implementation of a set of strict release standards in the United States that would necessarily be risk-based and supported by a comprehensive management scheme. Developing a policy of this kind, however, would entail the resolution of many issues, not the least of which would be public acceptance, including that of the metal industry, of the possible recycling of PRSM in the general commerce.

Decision Making↗
PubMed2006

An industry perspective on commercial radioactive waste disposal conditions and trends.

The United States is presently served by Class-A, -B and -C low-level radioactive waste and naturally-occurring and accelerator-produced radioactive material disposal sites in Washington and South Carolina; a Class-A and mixed waste disposal site in Utah that also accepts naturally-occurring radioactive material; and hazardous and solid waste facilities and uranium mill tailings sites that accept certain radioactive materials on a site-specific basis. The Washington site only accepts low-level radioactive waste from 11 western states due to interstate Compact restrictions on waste importation. The South Carolina site will be subject to geographic service area restrictions beginning 1 July 2008, after which only three states will have continued access. The Utah site dominates the commercial Class-A and mixed waste disposal market due to generally lower state fees than apply in South Carolina. To expand existing commercial services, an existing hazardous waste site in western Texas is seeking a Class-A, -B and -C and mixed waste disposal license. With that exception, no new Compact facilities are proposed. This fluid, uncertain situation has inspired national level rulemaking initiatives and policy studies, as well as alternative disposal practices for certain low-activity materials.

Decision Making↗
PubMed1956

The safe disposal of radioactive wastes.

A comprehensive review is given of the principles and problems involved in the safe disposal of radioactive wastes. The first part is devoted to a study of the basic facts of radioactivity and of nuclear fission, the characteristics of radioisotopes, the effects of ionizing radiations, and the maximum permissible levels of radioactivity for workers and for the general public. In the second part, the author describes the different types of radioactive waste-reactor wastes and wastes arising from the use of radioisotopes in hospitals and in industry-and discusses the application of the maximum permissible levels of radioactivity to their disposal and treatment, illustrating his discussion with an account of the methods practised at the principal atomic energy establishments.

Humans↗
PubMedDate not supplied

Radioactive materials in biosolids: national survey, dose modeling, and publicly owned treatment works (POTW) guidance.

The Nuclear Regulatory Commission (NRC) announced the availability of three new documents concerning radioactive materials in sewage sludge and ash from publicly owned treatment works (POTW). One of the documents is a report presenting the results of a volunteer survey of sewage sludge and ash samples provided by 313 POTWs. The second document is a dose modeling document, using multiple exposure pathway modeling focused on a series of generic scenarios, to track possible exposure of POTW workers and members of the general public to radioactivity from the sewage sludge or ash. The third document is a guidance report providing recommendations on the management of radioactivity in sewage sludge and ash for POTW owners and operators. This paper explains how radioactive materials enter POTWs, provides criteria for evaluating levels of radioactive material in sludge and ash, and gives a summary of the results of the survey and dose modeling efforts.

Data Collection↗
PubMed1985

[Effect of body loading on the specific blood radioactivity following 99mTc in-vivo erythrocyte labelling. The effects on determining end-diastolic volume in equilibrium radionuclide ventriculography].

In 40 patients who underwent stress-equilibrium-radionuclide-ventriculography, we examined the stress-induced change of blood radioactivity concentration. A significant (p less than 0.025) increase of blood radioactivity concentration after peak exercise (mean +7.2%) was found. This increase was the result of a significant (p less than 0.025) increase of the hematocrit (mean +4.7%) due to a decrease of the plasma volume. The changes of radioactivity concentration and hematocrit neither show any correlation with peak exercise value, integral exercise or duration of exercise, nor with the increase of heart rate or blood pressure. The increase of end-diastolic volume appears to result largely from a stress-induced increase of blood radioactivity concentration. Thus, radioactivity concentration should be measured before and after exercise when evaluating volume changes caused by stress-equilibrium-radionuclide-ventriculography.

Cardiac Output↗
PubMed1976

Radioactive colloidal solutions and suspensions for medical use.

Radioactive colloidal solutions and suspensions are being widely used in the diagnosis and treatment of various diseases. The author considers the behaviour or radioactive disperse preparations in the body and devotes particular attention to the reasons for isotope transition from the colloidal to the ionic state. Questions concerned with producing and investigating radioactive colloidal solutions are discussed. In the light of the physical and chemical properties of the radioisotopes and of the disperse systems themselves, the author considers methods of producing the more important radioactive disperse preparations: colloidal solutions of noble metals; colloidal solutions containing phosphorus-32, yttrium-90 and isotopes of the rare-earth elements; colloidal solutions with with indium-113m, gallium-68, technetium-99m and rhenium-186; suspensions (macroaggregates and microspheres) for the diagnosis of lung diseases; and radioactive colloidal solutions based on quaternary ammonium base compounds.

Colloids↗
PubMed1986

Transportation issues in nuclear medicine and the release of radioactivity into the environment.

Large volumes of radioactive materials are shipped daily over the nation's highways, by air, and by other transportation modes for a variety of purposes. These shipments include those intended for nuclear medicine applications. Shipments are governed by the Federal Department of Transportation, the Nuclear Regulatory Commission, and, for international shipments, the International Atomic Energy Agency. Knowledge of the regulations of these agencies is essential for maintenance of a viable radiation safety program. The use of radioactive materials is invariably accompanied by the potential for release of radioactivity into the environment. This potential is addressed in the recommendations and regulations of several voluntary and governmental agencies. Recently, new concepts have been introduced into these recommendations and regulations that use the concepts of "annual limit of intake," "committed effective dose equivalent," and "derived air concentrations." These concepts improve the applicability of present standards for the release of radioactive materials into the environment and for the protection of individuals from these materials.

Air Pollutants, Radioactive↗