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PubMed1979

Potential health and environmental effects of trace elements and radionuclides from increased coal utilization.

This report addresses the effects of coal-derived trace and radioactive elements. A summary of our current understanding of health and environmental effects of trace and radioactive elements released during coal mining, cleaning, combustion, and ash disposal is presented. Physical and biological transport phenomena which are important in determining organism exposure are also discussed. Biological concentration and transformation as well as synergistic and antagonistic actions among trace contaminants are discussed in terms of their importance in mobility, persistence, availability, and ultimate toxicity. The consequences of implementing the President's National Energy Plan are considered in terms of the impact of the NEP in 1985 and 2000 on the potential effects of trace and radioactive elements from the coal fuel cycle. Areas of needed research are identified in specific recommendations.

Animals↗
PubMed1993

The analysis of naturally-occurring radionuclides from uranium and thorium decay series in table mineral waters.

This project required the highly sensitive analysis of low-level alpha- and beta-emitters naturally occurring in table mineral water sold on the Swiss market. These radionuclides occur in the three major decay series-uranium-238, uranium-235, and thorium-232. The radionuclides analysed were 238U, 235U, 234U, 232Th, 230Th, 228Th, 210Po, 210Pb, and 226Ra. Many other radionuclides were determinable as a result of their equilibrium with an analysed nuclide. Efficient, element specific separation techniques were developed, allowing for the spectral analysis of each element without interference from other radioactive elements. Radioactive tracers, 232U, 230Th, and 209Po, were necessary to determine the percentage yield. These yields often varied greatly between different mineral waters, especially for thorium, ranging from 30 to 100%. Uranium, thorium and polonium isotopes could be directly analysed for by alpha-spectrometry. 226Ra was determined through the ingrowth of its daughter 222Rn by liquid scintillation counting. From the samples remaining after 210Po removal, the isotope's re-ingrowth from 210Pb determined the original 210Pb content. Limits of detection ranged from 0.1 to 2.0 mBq/l. The following contents were determined 234U + 238U 30-720 mBq/l; 232Th + 230Th < 1-5 mBq/l; 228Th 2-40 mBq/l; 226Ra 5-370 mBq/l; 210Po 1-90 mBq/l; 2,0Pb 1-90 mBq/l.

Mineral Waters↗
PubMed2005

Ion exchangers in radioactive waste management: natural Iranian zeolites.

Five samples of natural zeolites from different parts of Iran were chosen for this study. In order to characterize and determine their structures, X-ray diffraction and infrared spectrometry were carried out for each sample. The selective absorption properties of each zeolite were found by calculating the distribution coefficient (K(d)) of various simulated wastes which were prepared by spiking the radionuclides with (131)I, (99)Mo, (153)Sm, (140)La and (147)Nd. All the zeolite samples used in this study had extremely high absorption value towards (140)La; clinoptolite from Mianeh and analsite from Ghalehkhargoshi showed good absorption for (147)Nd; clinoptolite from Semnan and clinoptolite from Firozkoh showed high absorption for (153)Sm; mesolite from Arababad Tabas showed good absorption for (99)Mo; and finally mesolite from Arababad Tabas, clinoptolite from Semnan and clinoptolite from Firozkoh could be used to selectively absorb (131)I from the stimulated waste which was prepared. The natural zeolites chosen for these studies show a similar pattern to those synthetic ion exchangers in the literature and in some cases an extremely high selectivity towards certain radioactive elements. Hence the binary separation of radioactive elements could easily be carried out. Furthermore, these zeolites, which are naturally occurring ion exchangers, are viable economically and extremely useful alternatives in this industry.

Absorption↗
PubMedDate not supplied

National survey of elements and radioactivity in municipal incinerator ashes.

An analytical survey of fly ashes, bottom ashes and mixtures of the two for 36 elements, soluble salts and radioactivity was conducted. The ashes were taken from approximately one-fourth of the municipal solid waste incinerators presently operating in the United States. The concentrations of a number of toxic elements such as As, Cd, Cr, Cu, Hg, Ni, Pb, Sb, and Zn in specific ashes were high. The levels of radioactivity were not significant from a health standpoint. A number of ashes were exceedingly high in organic matter, indicating grossly inadequate conditions during incineration. Soluble salt content was appreciable in the ashes. The possible sources of elements in refuse and their behavior and fate during refuse incineration are discussed with respect to their chemical forms and properties and incinerator operating parameters. Variability of metal concentrations in ash with time of sampling and their solubilization in landfills are also considered.

Carbon↗
PubMed2000

Elemental and radioactive analysis of commercially available seaweed.

Edible seaweed products have been used in many countries, specifically Japan, as a food item. Recently these products have become popular in the food industry because of a number of interesting medicinal properties that have been associated with certain edible marine algae. Very little control exists over the composition of these products, which could be contaminated with a number of agents including heavy metals and certain radioactive isotopes. Fifteen seaweed samples (six local samples from the coast of British Columbia, seven from Japan, one from Norway and one undisclosed) were obtained. All samples were analyzed for multiple elements, using ICP mass spectrometry and for radioactive constituents. It was found that six of eight imported seaweed products had concentrations of mercury orders of magnitude higher than the local products. Lead was found at somewhat higher concentrations in only one local product. Laminaria japonica had the highest level of iodine content followed by Laminaria setchellii from local sources. Only traces of cesium-137 were found in a product from Norway and radium-226 was found in a product from Japan. Arsenic levels were found to be elevated. In order to estimate the effect of these levels on health, one needs to address the bioavailability and the speciation of arsenic in these samples.

British Columbia↗
PubMed2002

Environmental processes affecting plant root uptake of radioactive trace elements and variability of transfer factor data: a review.

Soil-to-plant transfer factors are commonly used to estimate the food chain transfer of radionuclides. Their definition assumes that the concentration of a radionuclide in a plant relates linearly solely to its average concentration in the rooting zone of the soil. However, the large range of transfer factors reported in the literature shows that the concentration of a radionuclide in a soil is not the only factor influencing its uptake by a plant. With emphasis on radiocesium and -strontium, this paper reviews the effects of competition with major ions present in the soil-plant system, the effects of rhizosphere processes and soil micro-organisms on bioavailability, the factors influencing transport to and uptake by roots and the processes affecting long-term uptake rates. Attention is given to summarizing the results of recent novel electrophysiological and genetic techniques which provide a physiologically based understanding of the processes involved in the uptake and translocation of radiocesium and -strontium by plants.

Biological Availability↗
PubMedDate not supplied

Pioneers of nuclear medicine, Madame Curie.

Among those who have made important discoveries in the field of radioactivity and thus helped in the development of nuclear medicine as an identical entity are: Heinrich Hertz who in 1886 demonstrated the existence of radiowaves. In 1895 Wilhelm Röntgen discovered the X-rays. In 1896 H. Becquerel described the phenomenon of radioactivity. He showed that a radioactive uranium salt was emitting radioactivity which passing through a metal foil darkened a photographic plate. An analogous experiment performed by S.Thomson in London was announced to the president of the Royal Society of London before the time H.Becquerel announced his discovery but Thomson never claimed priority for his discovery. Muarie Sklodowska Curie (1867-1934) was undoubtedly the most important person to attribute to the discovery of radioactivity. In 1898 she discovered radium as a natural radioactive element. This is how she describes the hard time she had, working with her husband Pierre Curie (1859-1906) for the discovery of radium and polonium: "During the first year we did not go to the theater or to a concert or visited friends. I miss my relatives, my father and my daughter that I see every morning and only for a little while. But I do not complain...". In presenting her discovery of radium, Madame Curie said: " ...in the hands of a criminal, radium is very dangerous. So we must often ask ourselves: will humanity earn or lose from this discovery? I, myself belong to those who believe the former...". The notebooks that Madame Curie had when she was working with radium and other radioactive elements like polonium, thorium and uranium are now kept in Paris. They are contaminated with radioactive materials having very long half-lives and for this reason anyone who wishes to have access to these notes should sign that he takes full responsibility. There are some more interesting points in Madame Curie's life which may not be widely known like: Although her full name is Maria Sklodowska-Curie, she is not known neither by that full name nor as Maria Sklodowska but as Marie Curie. Madame Curie was the second of five children. At the age of 24 she went to Sorbonne-Paris after being invited by her sister Bronja to study for about 2-3 years; instead she stayed in Paris for her whole life. Her doctorate was on the subject: "Research on radioactive substances" which she completed in six years under the supervision of H. Becquerel. Pierre Curie was Director of the Physics Laboratory of the Ecole Municipale of Physics and Industrial Chemistry when he married M. Curie in 1895. Pierre Curie left his other research projects and worked full time with his wife. In this laboratory M. Curie and her husband Pierre discovered radium and polonium. In 1901 Pierre Curie induced a radiation burn on his forearm by applying on his skin radiferous barium chloride for 10 hours. During World War I, M.Curie organized for the Red Cross a fleet of radiological ambulances each with X-ray apparates which were called "Little Curies". The X-ray tubes of these apparates were unshielded and so M.Curie was exposed to high doses of radiation. Once an ambulance fell into a ditch and M.Curie who was inside the ambulance was badly bruised and stayed at home for 3 days. M. Curie with her daughters, Irene and Eve, was invited and visited America in 1921. She led a successful campaign to collect radium for her experiments. Before leaving America, President Harding donated through her to the Radium Institute of Paris 1 g of radium for research purposes. At that time the process to obtain 0.5 g of pure radium bromide required 1 ton of ore and 5 tons of chemicals. No measures of radiation protection were taken back then. In 1929 Madame Curie visited the United States for a second time. She met with President Hoover and with the help of the Polish women's association in America collected funds for another gram of radium. Madame Curie died of leukemia on July 4, 1934. Sixty years after her death her remnants were laid to rest under the dome of the Pantheon. Thus she became the first woman under her own merit, to rest in the Pantheon. In 1934 at the Institute of Radiology in Paris, Frederique Joliot and Irene Curie-Joliot discovered artificial radiation. They studied alpha particles and beta;-radiation.

Editorial↗
PubMed1999

Study on the distribution of radioactive trace elements in vitamin D-overloaded rats using the multitracer technique.

The uptake and distribution of radioisotopes of beryllium, calcium, scandium, vanadium, chromium, manganese, iron, cobalt, nickel, zinc, gallium, arsenic, strontium and barium in vitamin D (VD)-overloaded rats were investigated and compared with those in control rats, using the multitracer technique. Each element revealed its characteristic distribution among various organs in control and VD-overloaded rats. For some elements, such as cobalt and chromium, the distribution patterns in them were significantly different. These results are discussed in terms of the metabolism of the elements in rats.

Acid Phosphatase↗
PubMed2003

Control of the risk of exposure to alpha emitting radionuclides in French nuclear power plants: example of Cattenom.

Control of the risk of internal exposure of EDF PWR plant maintenance workers by alpha-emitting radioactive elements is based on identification and quantification of the contamination of the systems. In 2001, an experiment carried out at Cattenom Power Plant during a unit outage in the presence of a leaking fuel cladding, based on measurement of alpha-emitting radioactive elements, made it possible to determine a realistic particle resuspension coefficient. A resuspension coefficient of 10(-6) m(-1) was adopted for operational radiological protection. An appropriate monitoring system for workers was set in place in collaboration with the occupational medicine and radiological protection department. It was based on prior estimation of the level of alpha contamination, and confirmed by swipe measurements, atmospheric surveillance by monitors, and collective analysis by nose blow samples from workers selected on the basis of their workstations, as well as supplementary individual measurements (monitoring of faeces). This surveillance made it possible to validate an appropriate work area monitoring system.

Actinoid Series Elements↗
PubMed2000

Measurement of excitation functions in the reactions 197Au(11C, xn)208-xAt using a radioactive 11C beam

A light-element radioactive ion-beam capability has been developed at the LBNL 88-Inch Cyclotron. The system is based on the coupled-cyclotrons method and utilizes short-lived species, e.g., 11C, 14O, 13N produced by (p,n) and (p,alpha) reactions at the LBNL Biomedical Isotope Facility Cyclotron. In a first experiment, 197Au(11C,xn)208-xAt excitation functions have been measured for energies ranging from the Coulomb barrier up to 110 MeV using a beam of 11C with intensities up to (1-2)x10(8) ions/sec on target. The results of this experiment are compared to measurements of 197Au(12C, xn)209-xAt excitation functions.

Journal Article↗
PubMed1990

[Experimental study on induction of lung cancer in hamster by fifteen chemical elements in the industrial dust from Yunnan Tin and other mines].

To exclude the carcinogenicity of trace radioactive elements in the mine powder and flue dust and clarify those inorganic chemical elements related to carcinogenesis of lung cancer, 15 non-radioactive inorganic chemical elements (CM1) responsible for mutagenesis, tumorigenesis and promotion of cancer from mine powder and flue dust were mixed for Ames test and carcinoma-inducing-experiment in animals. The results were as follows: 1. Ames test of CM1 showed positivity. 2. Lung cancer-inducing-experiment of CM1 in the hamster was successful with an incidence of 8.8% whereas in the control group, no lung cancer developed which showed that CM1 was related to the development of lung cancer. 3. Hyperplastic cells under light microscope showed Type II alveolar cells and Clara cells under electron microscope. It is possible that hyperplastic, precancerous and malignant cells in the lung are derived from these two kinds of cells. One case of multiple microcarcinoma was found in this experiment.

Animals↗
PubMed1994

[Role of single photon emission tomography (SPECT) in the exploration of cerebral ischemia].

Cerebral functional imaging has been greatly improved over the last ten years by the development of noninvasive techniques using radioactive elements emitting gamma radiation. Depending on the radioactive tracer used, these single photon emission computed tomography (SPECT) techniques provide either simple imaging of the distribution of local blood flows (99m Tc or 131 I labelled molecules) or quantitative imaging of the cerebral regional blood flow (133 Xe). Because of the rapidity of these techniques and the possibility of performing repeated examinations associated with dynamic test, quantitative measurement of cerebral blood flow with 133 Xe constitutes a value investigation for cerebral ischaemia by defining the site of the lesions, the distant consequences, the haemodynamic disturbances and their course over time. It has an even more important place in the preoperative assessment of stenoses and thromboses of the supra-aortic vessels and intracranial vessels: the study of the haemodynamic reserve by induced vasodilatation (injection of acetazolamide or acetazolamide test) provides valuable information necessary for the decision to perform a revascularisation procedure. In the future, 133 Xe SPECT will certainly be useful for determining the prognosis of an ischaemic cerebral vascular accident by means of very early examinations and to demonstrate the efficacy of new treatments for cerebral ischaemia by means of repeated examinations.

Blood Flow Velocity↗
PubMed1995

[Pages from history].

In March 1896, not long after the discovery of X rays by W. Röntgen, H. Becquerel discovers the "uranic rays" emitted by the element uranium. In 1898, M. Curie observes that minerals containing uranium are more radioactive than the uranium they contain; she infers that yet unknown radioactive elements are present in minute quantities in these minerals. A few months later, P. and M. Curie, after an exhausting labour, discover polonium and radium. The "physiological action" of the rays emitted by radium are observed for the first time in 1900-1901. E. Rutherford and F. Soddy show, in Montreal, in 1902, that radioactivity is a spontaneous transmutation of one chemical element in another. The discovery of the atomic nucleus and of nuclear reactions will lead F. and I. Joliot-Curie to discover artificial radioactivity in 1934.

France↗
PubMed2003

Diffusivity measurement of heavy ions in Wyoming montmorillonite gels by X-ray computed tomography.

Medical X-ray computed tomography (CT) was applied to the measurement of the diffusion coefficients of heavy ions in an artificial barrier material for the disposal of nuclear wastes. Cs(+), Sr(2+), I(-), and Br(-) are the heavy ions measured and the barrier used is the water-rich gel of Wyoming montmorillonite (86.5-100 wt.% H(2)O). X-ray CT yields an inevitable artifact (beam-hardening) in the obtained images. Before the diffusion experiments, the polychromatic primary X-ray spectrum of the CT scanner was measured by a CdZnTe detector, and the effects of the artifact were examined for an aqueous CsCl solution sample. The results show that the beam-hardening artifact derived from the polychromatic photon energy distribution can be suppressed by applying a special image reconstruction method assuming the chemical composition of samples. The transient one-dimensional diffusion of heavy ions in a plastic container filled with the gel was imaged nondestructively by the X-ray CT scanner with an in-plane resolution of 0.31 mm and slice thickness of 2 mm. The results show that diffusivities decrease with increasing clay weight fraction. The degree of the diffusivity decrease was high for cations (Cs(+) and Sr(2+)) and low for anions (I(-) and Br(-)). The quantitative decomposition of the contribution of the geometrical tortuosity and of the sorption to the diffusivity was performed by subtracting the diffusivity of nonsorbing I(-) from the measured diffusivities. The results show that the contribution of the sorption is large for Cs(+), Sr(2+) and small for Br(-). Because X-ray CT allows nondestructive and quick measurements of diffusivities, the technique would be useful particularly for measuring the diffusive migration of harmful radioactive elements.

Bentonite↗
PubMed1985

The characteristics of blood-borne radiolabels and the effect of anti-mouse IgG antibodies on localization of radiolabeled monoclonal antibody in cancer patients.

Quantitative and qualitative aspects of the blood survival of 131I and 111In-labeled monoclonal antibody 791T/36 have been examined in patients with colo-rectal carcinoma, ovarian carcinoma and osteogenic sarcoma who were receiving labeled antibody in diagnostic immunoscintigraphy trials. The blood clearance of intact antibody radiolabeled with either 131I or 111In was similar. A bi-phasic decline of both radiolabeled preparations was measured with initial half-lives 0.62 and 0.42 days for 131I and 111In labels and then with 1.85 and 1.40 day half-lives, respectively. The Fab fragment of the antibody was lost more rapidly (initial half-life 0.20 days and then 0.78 days). Blood-borne radioactivity was associated predominantly with plasma rather than cellular elements. Radioactivity was still attached to undegraded, uncomplexed, and immunologically active antibody as demonstrated by molecular filtration, immune precipitation, and antigen binding assays. However, anti-mouse-IgG antibody detected within 7 days of administration of radiolabeled antibody was present for at least 10 mo and has implications for the efficiency of repeated image studies.

Animals↗