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Applications of ICRP 30, ICRP 23, and radioactive waste risk assessment techniques to chemical carcinogens.

Linear, no threshold dose-response relationships at low doses are now accepted by U.S. Government agencies for risk assessment of chemical carcinogens. By application of ICRP30 metabolic models, ICRP23 data on ingestion intake of elements, and radioactive waste risk assessment techniques, it is shown that this predicts large numbers of eventual fatalities because of the high probability for material in the ground to eventually be ingested by humans. For example, a detailed for material in the ground to eventually be ingested by humans. For example, a detailed calculation shows that the cadmium released in U.S. coal burning in one year will eventually cause 20,000 fatal cancers (1000/GWe-yr of electricity production), the imports of cadmium into the U.S. will eventually cause 130,000 fatalities for each year of importing at the current rate, and CdS photovoltaic cells will cause 400 fatalities/GWe-yr.

Cadmium↗

Toxicological and cytophysiological aspects of lanthanides action.

Lanthanides, also called rare-earth elements, are an interesting group of 15 chemically active, mainly trivalent, f-electronic, silvery-white metals. In fact, lanthanides are not as rare as the name implies, except for promethium, a radioactive artificial element not found in nature. The mean concentrations of lanthanides in the earth's crust are comparable to those of life-important elements like iodine, cobalt and selenium. Many lanthanide compounds show particular magnetic, catalytic and optic properties, and that is why their technical applications are so extensive. Numerous industrial sources enable lanthanides to penetrate into the human body and therefore detailed toxicological studies of these metals are necessary. In the liver, gadolinium selectively inhibits secretion by Kupffer cells and it decreases cytochrome P450 activity in hepatocytes, thereby protecting liver cells against toxic products of xenobiotic biotransformation. Praseodymium ion (Pr3+) produces the same protective effect in liver tissue cultures. Cytophysiological effects of lanthanides appear to result from the similarity of their cationic radii to the size of Ca2+ ions. Trivalent lanthanide ions, especially La3+ and Gd3+, block different calcium channels in human and animal cells. Lanthanides can affect numerous enzymes: Dy3+ and La3+ block Ca2+-ATPase and Mg2+-ATPase, while Eu3+ and Tb3+ inhibit calcineurin. In neurons, lanthanide ions regulate the transport and release of synaptic transmitters and block some membrane receptors, e.g. GABA and glutamate receptors. It is likely that lanthanides significantly and uniquely affect biochemical pathways, thus altering physiological processes in the tissues of humans and animals.

Animals↗

Mineral imbalances in farm animals and their study and diagnosis with isotopic tracers.

Twenty-two mineral elements are known to be essential for animal life. These are calcium, phosphorus, sulphur, potassium, sodium, chlorine, magnesium, iron, iodine, copper, manganese, zinc, cobalt, molybdenum, selenium, chromium, tin, vanadium, fluorine, silicon, nickel and arsenic. Naturally occurring and man-made dietary imbalances of many of these elements and their interactions with other minerals are described and their functions and requirements by farm animals are outlined. The nature and importance of metabolic interactions among the mineral elements are discussed and the important concept stressed that there is no single minimum requirement or safe tolerance of a particular mineral, but a series of such minimum requirements and safe tolerances depending on the extent to which other minerals with which it interacts is present or absent from the diet. Radioactive tracer elements are shown to be of great value in the determination of mineral nutrient availability to the animal and for following mineral metabolic movements in the body. They are also shown to have considerable potential for the diagnosis of mineral imbalances. Various in vivo and in vitro techniques, involving both radioactive and stable tracers developed for the early diagnosis of mineral deficiencies are described and the strengths and weaknesses of such techniques in comparison with standard biochemical tests, are discussed. The need for further critical studies with isotopic tracers in the detection and diagnosis of mineral imbalances is emphasized. The main types of biochemical criteria used in the diagnosis of mineral deficiencies and excesses are given, with appropriate examples of their use.

Animals↗

Identification of radioactive materials in moving objects.

Control over the transportation of the radioactive materials crossing the borders of Uzbekistan is actually today not like before, because of increased threat of terrorism and urges of terrorist organizations to use radioactive materials in their terrorist activities. There are many companies producing radiation control systems. All such systems existing nowadays are based on the principles of intensity comparison for radiation detected by the system in the absence of control object and the intensity of the radiation when object appears. This method works well only in the conditions of constant or weakly changing background. However, at significant deviation in the value of background the number of false alarms set off by the systems increases. The present work describes the method for radioactive materials detection in the moving objects independent of the significant background deviations and present radiation monitoring establishment based on this principle.

Elements, Radioactive↗

Optically stimulated luminescence in forensics.

Tracking the former location of a radioactive source represents an attractive attribute in today's society, where the threat of a radiological dispersal device (RDD) is considered high. Development of a novel, retrospective detection technique based on optically stimulated luminescence is underway. This will allow confirmation of the former location of a radioactive source. Materials near the source's former location may be probed for information on accumulated dose by taking advantage of radiation-induced charge trapping that occurs in many common materials. The prototype detector design and analysis techniques are described.

Elements, Radioactive↗

Background radioactivity in sediments near Los Alamos, New Mexico.

River and reservoir sediments have been collected annually by Los Alamos National Laboratory since 1974 and 1979, respectively. These background samples are collected from five river stations and four reservoirs located throughout northern New Mexico and southern Colorado. Analyses include 3H, 90Sr, 137Cs, total U, 238Pu, 239,240Pu, 241Am, gross alpha, gross beta, and gross gamma radioactivity. Surprisingly, there are no federal or state regulatory standards in the USA that specify how to compute background radioactivity values on sediments. Hence, the sample median (or 0.50 quantile) is proposed for this background because it reflects central data tendency and is distribution-free. Estimates for the upper limit of background radioactivity on river and reservoir sediments are made for sampled analytes using the 0.95 quantile (two-tail). These analyses also show that seven of ten analytes from reservoir sediments are normally distributed, or are normally distributed after a logarithmic or square root transformation. However, only three of ten analytes from river sediments are similarly distributed. In addition, isotope ratios for 137Cs/238Pu, 137Cs/239,240Pu, and 239,240Pu/238Pu from reservoir sediments are independent of clay content, total organic carbon/specific surface area (TOC/SSA) and cation exchange capacity/specific surface area (CEC/SSA) ratios. These TOC/SSA and CEC/SSA ratios reflect sediment organic carbon and surface charge densities that are associated with radionuclide absorption, adsorption, and ion exchange reactions on clay mineral structures. These latter ratio values greatly exceed the availability of background radionuclides in the environment, and insure that measured background levels are a maximum. Since finer-grained reservoir sediments contain larger clay-sized fractions compared to coarser river sediments, they show higher background levels for most analytes. Furthermore, radioactivity values on reservoir sediments have remained relatively constant since the early 1980s. These results suggest that clay contents in terrestrial sediments are often more important at concentrating background radionuclides than many other environmental factors, including geology, climate and vegetation. Hence, reservoirs and floodplains represent ideal radionuclide sampling locations because fine-grained materials are more easily trapped here. Ultimately, most of these differences still reflect spatial and temporal variability originating from global atmospheric nuclear weapons testing and disintegration of nuclear-powered satellites upon atmospheric reentry.

Aluminum Silicates↗

Efforts of Uzbekistan to prevent nuclear terrorism and smuggling of radioactive and nuclear materials.

Uzbekistan is located on the cross-roads from the north--Russia, Western Europe--to the south--Afghanistan, Iran, Iraq and others. The appearance of terrorist organizations urged some Asian countries to make the nuclear weapons, the making the task of stopping the transportation of nuclear materials and technologies from the north (from countries possessing nuclear weapon) to the south (to countries desiring to have weapons and its components) a reality. To resolve this problem, on the main transportation routes, "Yantar" stationary radiation monitors of Russian production were installed, and development and production of monitors of our own make was started. This paper covers these works as well as those on preventing possible terrorist attacks on nuclear objects of Uzbekistan.

Elements, Radioactive↗

[Effects of one cycle of inhalation crenotherapy with radioactive fluoridated oligomineral].

The objective of the study was to test the effects of inhalation crenotherapy using the radioactive, fluoridated oligomineral waters from the Merano Spa on both subjects with specific upper respiratory tract phlogosis and normal subjects. The double-blind study was performed on a population of 27 adults of both sexes treated with radioactive-fluoridated water (group A) and 20 subjects, suffering from the same chronic catarrh pathology, selected with the same criteria but treated with inhalation of steam and an aerosol using drinking water from the municipal water supply (group C). In addition, a group of 13 subjects--which in terms of age and sex were statistically comparable to groups A and C but who did not show any signs of acute or chronic upper respiratory tract pathologies (group B) were also treated with the radioactive-fluoridated waters. All subjects included in the study underwent the following tests before and after the cycle of crenotherapy: Objective E.N.T. examination. Computerized Active Anterior Rhinomanometry. Detection of the ciliary mucous transport (CMT) time. Nasal cytology. Physical and immunochemical examination of the nasal mucous. The results of this study--seen in the trend in some parameters monitored both before and after the cycle of crenotherapy using Merano Spa water--clearly show that that the crenotherapy studied had an effect on aspecific chronic phlogosis of the upper respiratory tract. In fact, among other things, group A showed decreased nasal resistance, increased nasal respiratory flow, normalized mucociliary transport, decreased bacterial flora and an increased number of plasma cells in the rhinocytogram. In addition there was an increase in the following values in the nasal mucous: Albumin, non-secretory Immunoglobulin and the secretory portion of secretory Immunoglobulin A. None of these variations are seen in the results from the control group treated with municipal drinking water. After treatment with Merano spa water, the pathology-free subjects showed variations in the parameters in line with those found for group A. This biological reality can most likely be attributed to the favorable response of the respiratory mucosa, promoting anti-infection defenses.

Acute Disease↗

USAN assigned to radioactive pharmaceutical.

The United States Adopted Names (USAN) applicable to radioactive pharmaceuticals are composed of the names of the basic compound serving as the carrier for the radioactivity, the symbol for the radioactive isotope, and the atomic weight (since several radioactive isotopes of a given element may be in use--see listing under iodine). The following listing of nonproprietary names (shown in boldface type) is arranged in alphabetical order according to the English name of the radioactive element. The isotopes of hydrogen are listed under their specific names, deuterium and tritium. Radioactive pharmaceuticals are often supplied by the manufacturers under a designation equivalent to the adopted nonproprietary name and are listed as such; specific trademarks are given in brackets when they exist. Basic information relative to these lists was given in the editorial that accompanied the first such listing.

Pharmaceutical Preparations↗

The possible influence of the components of the soil and the lithosphere on the development and growth of neoplasms.

The author reviews the background of the soil-cancer relationship. The study then goes into geocarcinogenic diseases in relation to soil composition, looking first at general factors: soil concentrations of selenium, caesium-rubidium-potassium, trace elements; natural radioactivity risks; cancer risks in connection with recycled waste water. In its final part, the study examines geocarcinogenic diseases linked with soil composition covering gastric cancer, cancer of the esophagus, urinary, breast, and bronchial cancer, pleural mesotheliomae and bone cancer.

England↗

[Combined arthroscopic and radiation synovectomy in rheumatoid arthritis].

In rheumatoid arthritis of the knee joint good results are obtained using arthroscopic synovectomy or radiation synovectomy. Aim of our study was to investigate, whether the combination of these two minimal invasive interventions achieves better results. First we performed arthroscopic synovectomy of the knee joint followed by radiation synovectomy with application of 111-222 MBq Yttrium-90 6 weeks later. In a prospective randomised clinical trial between 1987 and 1991 we performed radiation synovectomy on 22 knee joints and combined arthroscopic and radiation synovectomy on 26 knee joints. We explored the patients preoperatively, 6 weeks and 6 months postoperatively. In 1996 we evaluated 141 knee joints in a retrospective clinical trial. 90 Knee joints had been treated with the combined therapy, 39 only with radiation synovectomy and 12 only with arthroscopic synovectomy. Depending on the three different therapeutic interventions, the patients were classified into midterm (3-5 years) and long-term (6-8 years) observation groups. The trials are based on the standardized ARO-Questionnaire of the knee joint, the modified ARO Knee-Score and the radiological grading according to Larsen, Dale and Eek. In the prospective clinical trial we found significant better results for patients treated with the combined therapy than for patients treated with radiation synovectomy only regarding the parameter swelling, effusion, range of motion, pain and Knee-Score. In the long-term results of the retrospective clinical trial the patients treated with the combined therapy showed a significant better outcome for the parameters pain, swelling and Knee-Score, than the patients treated with radiation synovectomy. Although no statistically significant difference was found comparing the results of the combined therapy with arthroscopic synovectomy, an improvement of the clinical outcome can be observed performing arthroscopic synovectomy followed by radiation synovectomy. In the treatment of rheumatoid arthritis of the knee joint a better outcome is achieved performing combined arthroscopic and radiation synovectomy than performing only one of the methods.

Arthritis, Rheumatoid↗

Long-term benefit of radon spa therapy in the rehabilitation of rheumatoid arthritis: a randomised, double-blinded trial.

This study investigates the effects of radon (plus CO2) baths on RA in contrast to artificial CO2 baths in RA rehabilitation using a double-blinded trial enrolling 134 randomised patients of an in-patient rehabilitative programme (further 73 consecutive non-randomised patients are not reported here). The outcomes were limitations in occupational context/daily living (main outcome), pain, medication and further quantities. These were measured before the start, after the end of treatment and quarterly in the year thereafter. Repeated-measures analysis of covariance (RM-ANCOVA) of the intent-to-treat population was performed with group main effects (GME) and group x course interactions (G x C) reported. Hierarchically ordered hypotheses ensured the adherence of the nominal significance level. The superiority of the radon treatment was found regarding the main outcome (RM-ANCOVA until 12 months: p(GME) = 0.15, p(G x C) = 0.033). Consumption of steroids (p(GME) = 0.064, p(G x C) = 0.025) and NSAIDs (p(GME) = 0.035, p(G x C) = 0.008) were significantly reduced. The results suggest beneficial long-term effects of radon baths as adjunct to a multimodal rehabilitative treatment of RA.

Activities of Daily Living↗

Burning radionuclide question: what happens to iodine, cesium and chlorine in biomass fires?

Fires can mobilize radionuclides from contaminated biomass through suspension of gases and particles in the atmosphere or solubilization and enrichment of the ash. Field and laboratory burns were conducted to determine the fate of I, Cs and Cl in biomass fires. Straw, wood, peat, dulse (seaweed) and radish plants were combusted with temperatures varying from 160 to 1000 degrees C, representing the normal range of field fire temperatures. Loss to the atmosphere increased with fire temperature and during a typical field fire, 80-90% of the I and Cl, and 40-70% of the Cs was lost to the atmosphere. The remainder was left behind in the ash and was soluble. Typically, the ash was enriched in I by a factor of two to three, with higher enrichments of Cs and lower enrichments of Cl, when compared to the initial fuel concentration during field burns. Most of the I was lost to the atmosphere as a gas. If the elements were radioactive isotopes, such as 129I, 137Cs and 36Cl, fires could cause an increased radiological dose to people through inhalation, exposure to ash, or ingestion of plants because of increased uptake of ash leachate.

Air Pollutants, Radioactive↗

Determination of plutonium in environmental samples by AMS and alpha spectrometry.

Environmental samples from nuclear weapons test sites at the atolls of Mururoa and Fangataufa (French Polynesia, south Pacific) have been analyzed for their content of plutonium isotopes by applying the independent techniques of decay counting (Alpha Spectrometry) and accelerator mass spectrometry (AMS). Here, we propose the combination of both techniques which results in a maximum of information on the isotopic signature of Pu in environmental samples. Plutonium was chemically separated from the bulk material by anion exchange. (242)Pu was used as an internal standard for both AMS and alpha spectrometry. The samples for alpha spectrometry were prepared by micro-precipitation with NdF(3). After alpha spectrometry, the samples were reprocessed for AMS. Pu was co-precipitated with Fe(OH)(3) and finally, solid samples were prepared. At the VERA (Vienna Environmental Research Accelerator) facility, the various Pu isotopes were separated by their isotopic masses and quantified by the AMS technique. A good agreement of the results obtained from the AMS measurements was found with those obtained from Alpha Spectrometry. Overall, the data agree on average within 10% of each other. Isotope ratios for (238)Pu, (239)Pu and (240)Pu can be extracted from our investigations. Alpha spectrometry delivers data for the (238)Pu and the combination of ((239+240))Pu concentrations in those samples. In addition, the AMS technique provides information on the individual concentrations of (240)Pu and (239)Pu.

Alpha Particles↗

Advanced gamma ray technology for scanning cargo containers.

The shipping industry is striving to increase security for cargo containers without significantly impeding traffic. Three Science Applications International Corporation (SAIC) development programs are supporting this effort. SAIC's ICIS system combines SAIC's VACIS gamma ray imaging, radiation scanning, OCR, elemental analysis and other technologies to scan containers for nuclear materials and other hazards in normal terminal traffic. SAIC's enhanced gamma ray detector improves VACIS image resolution by a factor of three. And SAIC's EmptyView software analyzes VACIS images to automatically verify empty containers.

Elements, Radioactive↗

Transfer of selected elements from food into human milk.

OBJECTIVES: We measured the transfer factors of antimony, cerium, chromium, cobalt, gallium, lanthanum, molybdenum, niobium, ruthenium, silver, thorium, titanium, and uranium from food to milk in nursing mothers. METHODS: Food and milk samples from 19 mothers were taken daily over 2 to 8 wk. The samples were analyzed for element content after microwave-assisted pressure digestion with a mass spectrometer and inductively coupled plasma. The transfer factor, or the portion of element intake passed on in the milk, was calculated as the element concentration in food (g/kg) divided by the element concentration in milk (g/L). RESULTS: The calculated transfer factors were 5.1 for silver, 16.1 for cerium, 6.9 for chromium, 8.4 for cobalt, 19.1 for gallium, 13.8 for lanthanum, 77.4 for molybdenum, 20.7 for niobium, 4.1 for ruthenium, 13.2 for antimony, 20.2 for thorium, 5.6 for titanium, and 21.3 for uranium. Factors differed significantly across individuals. CONCLUSION: These differences can be attributed to the fact that the different levels of elements in breast milk are the result of individual differences in milk production and factors other than the amount of any particular element absorbed by the body.

Adult↗

Estimation of thermal neutron absorption cross-section from K, U and Th concentrations for Miocene rocks from the Carpathian Piedmont in Poland using artificial neural networks.

The radiometric K, U and Th concentrations and neutron absorption cross-section sigma a of rock samples obtained from coring are analysed. The cores are from wellbores located in the Sucha-Jordanów region (Carpathian Mountains) and from gas producing Miocene formations in the Carpathian foothills. Correlation coefficients between the neutron absorption cross-section (sigma a) and K, U and Th concentrations are presented. Neural network representation of the function sigma a = f(K, U, Th) obtained for a region can later be used for sigma a estimation from spectrometric probe results in uncored wells.

Elements, Radioactive↗