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At least 1,189 records · Page 66Linked to original sources
PubMed1991

[Level and pattern of morbidity of children residing in the Ukrainian S.S.R. exposed to radioactive pollution as the result of the Chernobyl AES accident].

It has been shown that there is a significant increase in total morbidity in children residing in the areas exposed to radioactive pollution due to the accident at the Chernobyl Atomic Power Station. This is due largely to higher morbidity of respiratory disease. There is also an increased in the incidence of digestive diseases, iron-deficiency anemias, mental disorders. The recorded growth of childhood morbidity in the areas examined is much higher than that in the children living in other areas unexposed to radioactive pollution.

Accidents↗
PubMed1990

Radioactivity in human milk.

A brief introduction outlines the sources of radionuclides in the environment, their diffusion and transfer to different environmental compartments and their pathways to individuals; definitions of the main quantities and measurement units used in the study are included. A review is given on published data concerning the radioactive contamination of human milk after the Chernobyl accident. The authors' investigation on breast milk contamination in Italy in the same period is discussed together with an examination of the natural radioactive content. Finally, possible future developments and prospects of the research on this issue are explored.

Accidents↗
PubMed1987

Radioactive colloidal gold as a tool to quantify extravasation of macromolecules in the rat cremaster muscle.

Since previously described simple methods were too insensitive to quantify the extent of microvascular permeability increase in the rat cremaster muscle, we applied a new quantitative technique using radioactive colloidal gold (198Au) as the macromolecular tracer. Dose-response effects on microvascular permeability were found with increasing doses of subscrotally injected serotonin or histamine. The presence of colloidal gold particles in the subendothelial space of the postcapillary venules, as verified ultrastructurally, indicated endothelial permeation of the tracer macromolecules. The increased permeability elicited by serotonin was inhibited in a dose-dependent way by serotonin receptor antagonists (potency: methysergide greater than or equal to ketanserin = ritanserin greater than cinanserin), suggesting the presence of functional S2-serotonergic receptors on postcapillary venular endothelial cells. A dose-related inhibition of the histamine-induced extravasation was seen with the H1 antagonists astemizole and azatidine (astemizole greater than azatidine); the H2 antagonists cimetidine and ranitidine had no inhibitory effect. The radioactive colloidal gold technique is a sensitive and reliable tool for pharmacological experiments aimed at investigating the extravasation phenomenon in small tissue samples such as the rat cremaster muscle.

Animals↗
PubMed1987

Effects of radioactive decay and their implications on in vivo metabolic imaging.

In the context of medical radionuclide imaging, possible consequences of molecular disruption that is due to radioactive decay and of the positron range are discussed. Radioactive decay may cause extensive disruption to the labeled molecule particularly if the transformation involves the creation of an inner shell vacancy. The movement of a positron away from the site of emission implies that the positron will annihilate in a region not disrupted by the decay. Neglect of the photon angular correlation disregards information on the physical and chemical state of the sample.

Humans↗
PubMed1987

Radioactive uranium in various Indian tobaccos and consumable products (snuff, chutta, bidi and cigarette).

Tobacco is chewed in the form of snuff and thus its radioactivity--if there is any--goes directly into the body. Besides normal smoking, tobacco is also smoked in reverse manner in the form of "chutta", an indigenously prepared cigar made from the home grown plants of Nicotinia tobacum in South East coastal towns and villages in India. The burnt residue and the radioactive element--if there is any--in the case of chutta smoking will also go directly in the body causing hazardous effects. Uranium traces were determined in commercially available samples of snuff, chutta, bidi and cigarette tobacco using radiation damage etch technique. The analysis showed that uranium levels varied from 7.4 to 19.1 ppm in snuff, 0.16 to 0.37 ppm in chutta, 0.13 to 0.23 in bidi and 0.037 to 0.12 ppm in cigarette tobacco.

Humans↗
PubMed1993

[Protection of the Croatian population from accidental radioactive contamination of the food chain].

The paper indicates the importance of investigating radionuclide translocation in the human food chain, and the contribution of selected food components in total exposure of the population after accidental radioactive contamination. Data on radioactive contamination and risk assessment of the Croatian population after the Chernobyl nuclear accident are given and possibilities of decontamination of food chain components are discussed. Literature data on radionuclide removal from the human food chain are compared to the results of own investigations. Emphasis is placed on biologically most important radionuclides, 131I, 90Sr, 137Cs, and the most effective means of protection are sought. The preventive measures following a nuclear accident should be based on the cost-benefit principle i.e. the damage from applying radiation protection measures should not exceed the benefit from possible dose reduction.

Accidents↗
PubMedDate not supplied

[The radioecological problems of Eurasia and the sources of radioactive environmental contamination in the former USSR].

There is three major sites of radioactive environmental contamination in the former USSR: the Chelyabinsk region in the Urals, Chernobyl NPP in Ukraine and Novaya Zemlya in the Arctic Ocean. The first mentioned is the most important with regard to local (potential) contamination, the last one dominates the global contamination. A number of sites and sources are less well known with regard to environmental contamination. This is thus the case for the plutonium production factories at Tomsk and Dodonovo. More information on nuclear reactors in lost or dumped submarines is also needed. From a global point of view reliable assessment of the radioactive run-off from land and deposits of nuclear waste in the Arctic Ocean are in particular pertinent.

Accidents↗
PubMedDate not supplied

Unique behavior of rubidium in mice under low oxygen atmosphere. Simultaneous tracing of Sc, Mn, Fe, Co, Zn, Se, Rb, Y, and Zr using off radioactive multitracer technique.

Relative tissue distributions of Sc, Mn, Fe, Co, Zn, Se, Rb, Y, and Zr tracers were studied in young mice housed under four different O2 atmospheres (10 percent, 20 percent, 80 percent, and 100 percent O2) using the radioactive multitracer technique developed at The Institute of Physical and Chemical Research (RIKEN). At 48 hr after injection of the multitracer, the tissue uptake rates were examined for 10 tissues (brain, cardiac muscle, lung, liver, spleen, pancreas, kidneys, skeletal muscle, bone, and blood) and expressed as the radioactivity percentage of the injected dose per gram of wet tissue (percent dose/g). Rubidium uptake rates for all soft tissues of mice housed under a 10 percent O2 atmosphere were found to be higher than those of the tissues of mice housed under the other three O2 atmospheres (20 percent, 80 percent, and 100 percent), but no difference was observed for the other elements (Sc, Mn, Fe, Co, Se, etc.) under any of the O2 atmospheres.

Animals↗
PubMed1998

Radioactivity measurements of ytterbium-169 brachytherapy sources.

Ytterbium-169 is being considered as a new radiation source for brachytherapy applications. This radioisotope emits photons with energies ranging from 50 to 308 keV (average energy 93 keV) and decays with a half life of 32 days. For these reasons, it is believed to offer radiological and radiobiological advantages over some other isotopes currently in use. One impediment to widespread clinical use of this isotope is the determination of source strength in units of air kerma rate [cGy h-1]. The source strength can be measured directly with an ion chamber or calculated indirectly from the source radioactivity [Bq] with corrections for encapsulation. Our attempts to reconcile these two approaches have led to the development of a spectrometric technique for determining the radioactivity of ytterbium-169 brachytherapy seeds. A High Purity Germanium (HPGe) spectrometer is used to count the 307.7 keV photon emitted within a defined solid angle. The intrinsic photopeak efficiency of the detector was determined by Monte Carlo simulation followed by experimental verification with an activity-calibrated europium-152 source. Finally, the HPGe system has been used to calibrate a re-entrant ionisation chamber, allowing routine of Ytterbium source activity for clinical applications.

Brachytherapy↗
PubMed1964

RADIOACTIVITY MEASUREMENTS IN ALASKAN ESKIMOS IN 1963.

During the summer of 1963 people at five villages above the Arctic Circle in Alaska were measured for accumulated radioactivity with a portable whole-body counter. Adults of the interior village of Anaktuvuk Pass showed the highest average body burden, 628 nanocuries of cesium-137. This is an increase of nearly 50 percent over the summer before. The maximum burden foundwas 1.24 microcuries.

Adult↗
PubMed1978

Environmental radioactivity in the Faroes in 1977.

Measurements of fallout radioactivity in the Faroes in 1967 are presented. Strontium-90 (and 137Cs in most cases) was determined in regularly collected samples of precipitation, grass, milk, fish, sea water, bread, and drinking water. In addition, analyses were made of spot samples of lamb, sea birds, potatoes, sea plants, vegetables, eggs, and human bone. Estimates are given of the mean contents of 90Sr and 137Cs in the human diet in the Faroes in 1977.

Adult↗
PubMedDate not supplied

Sorption of radioactive contaminants by sediment from the Kara Sea.

The purpose of this study is to quantify some of the parameters needed to perform near-field modelling of sites in the Kara Sea that were impacted by the disposal of radioactive waste. The parameters of interest are: the distribution coefficients (Kd) for several important radionuclides, the mineralogy of the sediment, and the relationship of Kd to liquid-to-solid ratio. Sediment from the Kara Sea (location: 73 degrees 00'N, 58 degrees 00'E) was sampled from a depth of 287 m on August 23/24, 1992. Analysis of the material included mineralogy, grain size and total organic carbon (TOC). Uptake kinetics were determined for 85Sr, 137Cs, 241Am, 99Tc, 1251, 232U and 210Pb and distribution coefficients (Kd) were determined for these radionuclides using batch type experiments. Sorption isotherms, developed for 137Cs, 85Sr and 99Tc, were linear in each case. Increasing the liquid-to-solid ratio strongly increased uptake of 137Cs and moderately increased uptake of 99Tc. Analysis for anthropogenic radionuclides indicated the presence only of 239/240Pu in the sediment with the highest activity (at the top section of the core) being 0.420 Bq kg(-1). Other anthropogenic radionuclides were below detection limits.

Absorption↗
PubMed1975

Environmental Radioactivity in Denmark in 1974.

The present report deals with the measurement of fall-out radioactivity in Denmark in 1974. Strontium-90 was determined in samples from all over the country of precipitation, soil, ground water, sea water, grass, dried milk, fresh milk, grain, bread, potatoes, vegetables, fruit, total diet, drinking water, and human bone. Furthermore, 90Sr was determined in local samples of air, rain water, grass, sea plants, fish, and meat. Caesium-137 was determined in soil, sea water, milk, grain products, potatoes, vegetables, fruit, total diet, fish, and meat. It was also measured by wholebody-counting of a control group at Tisø. Estimates of the mean contents of radiostrontium and radiocaesium in the human diet in Denmark during 1974 are given. The gamma-background was measured regularly at locations around Risø, at ten of the State experimental farms, in one area in Zealand, one in Jutland, and along the shores of the Great Belt. Finally the report includes routine surveys of environmental samples from the Risø area.

Air Pollution, Radioactive↗
PubMed2001

Environmental impact of radionuclide migration in groundwater from a low-intermediate level radioactive waste repository.

The radionuclide migration from a certain Chinese repository with low-intermediate level radioactive solid waste is studied. The migration in groundwater is analyzed and computed in detail. Under presumption of normal releasing, or the bottom of the repository has been marinated for one month with precipitation reaching 600 mm once and a 6 m aerated zone exists, a prediction for 7 radionuclides is conducted. It shows that the aerated zone is the primary barrier for migration. The migration for radionuclides 60Co, 137Cs, 90Sr, 63Ni, etc. will be retarded in it within 500 years. The concentration of 239Pu will be decreased by amount of 6 order. Only 3H and 14C can migrate through the aerated zone. The radionuclides that go through the aerated zone and enter the aquifer will exist in spring, stream and sea. Based on this, the intake dose by residents in different age group resulting from drinking contaminated spring water, eating seafood is calculated. The results showed that the impact of the repository to the key resident group is lower than the limit in national repository regulation standard. This complies with the repository management target.

Air↗
PubMed2006

[Removing radioactive waste from enterprises and territories of Moscow and central region of Russia is a main goal of RADON Industrial Research Association].

The article contains brief historical data on foundation of radiation accident department in "RADON" Industrial Research Association, list and extent of the department works since 1995 on liquidation of various radioactive pollutions, decontamination methods applied, operative equipment and devices. The authors present methodic documents elaborated by the department specialists on decontamination of territories, compartments, etc.

Chernobyl Nuclear Accident↗
PubMed1977

Environmental radioactivity in the Faroes in 1976.

Measurements of fall-out radioactivity in the Faroes in 1976 are presented. Strontium-90 (and 137Cs in most cases) was determined in regularly collected samples of precipitation, grass, milk, fish, sea water, bread, and drinking water. In addition, analyses were made of spot samples of lamb, sea birds, potatoes, sea plants, vegetables, eggs, and human bone. Estimates are given of the mean contents of 90Sr and 137Cs in the human diet in the Faroes in 1976.

Animals↗
PubMed1979

Radioactive and bioassay of intraocular antibiotics: double-assay technique to compare penicillin G, cefamandole, and gentamicin in ocular tissues in vivo.

We examined the correlation between radioactive assay and trephine-discbioassay of penicillin G sodium, cefamandole nafate, and gentamicin sulfate in ocular tissues of pigmented rabbits after subconjuctival administration of antibiotic. We devised a technique whereby a single sample of tissue could be assayed by both methods. This was achieved by performing the bioassay first, then measuring the resudual radioactivity in the agar and specimens. The results of both methods were generally within 13%. An exception was gentamicin in iris and choroidretina, for which the bioassay result was strikingly less than the radioassay value. No such discrepancy was evident when similar studies were carried out with gentamicin in albino rabbits. This suggests that the phenomenon is due to tight binding of gentamicin by melanin-containing tissues. The trephine-disc bioassay provides an accurate measure of diffusible bioactive antibiotic in ocular tissues.

Animals↗