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Abstract  

Instrumental Neutron Activation Analysis /INAA/ has been employed for the determination of 15 major, minor and trace elements in human and animal blood samples. Dry whole blood samples along with NBS and IAEA standards were irradiated for 5 min, 1 h, 5 h and 10 h with reactor thermal neutrons and counted using high resolution -spectrometry at successive intervals. Data for a new IAEA proposed CRM Mixed Human Diet /H-9/ is reported.

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Abstract  

This paper reviews the methodology used in the execution and interpretation of animal studies (mostly conducted at NRPB) designed to provide guidance on limits of intake and the effectiveness of chest monitoring for persons exposed to various uranium, plutonium, americium, and thorium bearing dusts. The lung retention and transportability characteristics of the actinides in humans have been predicted by combining the absorption rates into blood calculated from the animal studies with particle transport rates from the alveolar region of the human lung. This approach is compatible with the application of the new ICRP respiratory tract model.The results of the animal experiments demonstrate the diversity of the absorption rates for the different chemical forms of the actinides and their disparity from the default values proposed by ICRP for Type F, M, and S compounds in the absence of specific data. The predicted lung retention kinetics of the actinides in humans provide the basis for assessing the validity of chest monitoring; for this purpose the most recent ICRP values for doses per unit intake and deposition in the alveolar region of the lungs have been taken into account. The results show that for some dusts, the data can be interpreted with confidence, while for others the method is impracticable or has considerable uncertainty. Overall, the results support the ICRP recommendation that material specific information is to be preferred for setting limits on intake and interpreting monitoring data.The paper concludes with suggestions for further work.

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Due to changes in the Hungarian legislation, the ATEVSZOLG Corporation, which treats waste of animal origin, has started to search for a new way to dispose and reuse this waste by recycling it without the loss of materials produced at high cost from the natural cycle. Since this waste contains a high concentration of fat, one major objective of the composting experiment was to investigate the effect of composts with high fat contents on the biological activity of the soil. The other aim was to investigate the impact of sterilising heat treatment and of high temperature conditions during the composting process on the number of pathogenic microbes, which are common in waste of animal origin. The quality and quantity of the fat in the soil samples were measured using a gas chromatograph. The effect of the high fat content on the biological activity of the soil was measured as the difference between the control and the treated soil samples for CFU number of fat-degrading microbes and the difference in the biological activity of the samples in an Oxi-Top soil respirator system. The effect of heat treatment on pathogenic microbes was investigated on the basis of the number of Clostridium, faecal coliforms and Pseudomonas aeruginosa microbes. The results showed that the high fat content deposited with the composts was well utilised, and that its degradation did not cause a problem for the microbes living in the soil. This was proved both by the results of the CFU experiments and by the parameters in the Oxi-Top soil respirator system. The heat treatment successfully decreased the number of pathogenic microbes to a low risk level. The results indicated that the mixing of the heat-treated, sterilised basic materials of the composts with untreated, non-sterilised materials such as sewage sludge should be avoided, due to the risk of re-infecting the compost with pathogens. The composts produced from animal waste using the heat treatment developed by the ATEVSZOLG Corp. have the same infection risk as the composts produced from animal manure or sewage sludge.

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Acta Biologica Hungarica
Authors: Á. Horváth, P. Sántha, V. Horváth, Nóra Török, I. Nagy, G. Jancsó, Cs. Vágvölgyi, and F. Somogyvári

A new, rapid method is described which permits the genotyping of genetically modified animals from a microlitre volume of whole blood samples via one step polymerase chain reaction amplification. The major advantage of the presented method is the exclusion of a DNA preparation step, which significantly reduces the time expenditure and work load of the genetic testing. Pilot studies indicate, that this method is efficient and applicable also on tissue biopsies and larger amount of blood providing a rapid and reliable new technique over conventional genotyping approaches.

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Abstract  

Radioactive skin contamination with radionuclides in ionic forms after the permeation across skin models was studied in vitro. Using animal skin models of 5-day-old rat and 9-day-old rat, either intact or stripped, it was found that besides the transepidermal also the transfolicular flux can be important. Stratum corneum was found to be the principal permeation barrier in all cases. The study of penetration — time profiles revealed that permeated amounts were proportional to time in the case of 137Cs+ and 60Co2+, but they showed a local maximum in the case of 147Pm3+.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: J. Mietelski, P. Gaca, P. Zagrodzki, M. Jasińska, M. Zalewski, M. Tomczak, N. Vajda, and E. Dutkiewicz

Abstract  

Activity concentration of 90 Sr and stable strontium concentration was analysed in 42 samples of animal (deer, roe-deer, elk and boar) bones, which mostly originated from north-eastern Poland. Strontium separation was performed by extraction chromatography. Determination of chemical yield was controlled by means of stable Sr determination using atomic spectrometry at the beginning and at the end of the separation procedure. Equilibrated 90 Sr and 90 Y activity was measured using a liquid scintillator spectrometer. Stable strontium range was from 55.4±1.7 ppm to 91.8±4.5 ppm, the mean was 71.84 ppm with a standard deviation (SD) of 9.31 ppm. The mean recovery of strontium was 26.7% with SD = 16.1%. The maximum activity of 90 Sr, equal to 629±13 Bq/kg (ash) was found for a deer sample from Augustów Primeval Forest. In average, deer show the highest radiostrontium level, followed by roe-deer, elk and the lowest level were observed for boar. Differences between boar and deer or roe-deer are significant in terms of Kruskal-Wallis statistical test. Animal bones from north-eastern Poland showed about twice the mean concentration of 90 Sr, compared to those of south-central Poland, but the difference was found not significant. Activities observed in roe-deer bones suggest the deposition of a concentration of 1.9 to 3.5 kBq/m2 in the average of Chernobyl-origin 90 Sr in 1986 in north-eastern Poland.

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Acta Biologica Hungarica
Authors: Danica Matusovits, Zsuzsanna Suba, D. Takács, Kinga Turzó, K. Donath, and A. Fazekas

The aim of this pilot investigation was to develop a new animal model for studying the effects on osteogenesis of agents used in the guided bone regeneration technique. As test material, a mixture of two osseoconductive materials with different physico-chemical characteristics was used. One component of the mixture was Bio-Oss, a bovine hydroxyapatite; the other was Cerasorb, a synthetic tricalcium phosphate. The mixture consisited of 50 volume percent of Bio-Oss and 50 volume percent of Cerasorb. In in vivo pilot experiment, bone wounds were prepared in the proximal third of both femurs of rabbits. A Cerasorb + Bio-Oss mixture was inserted on the test side and the same amount of sterile buffered physiological solution on the control side. After healing for 4 weeks, the bone segments were embedded and cut without decalcification, using the Exact cutting and grinding system. The density of the newlyformed bone was evaluated histomorphometrically. On the Cerasorb + Bio-Oss test side the bone density was almost 1.5 times higher than that on the control side. These results demonstrated that the applied animal model is appropriate for investigation of the effects on osteogenesis of biocompatible graft materials such as Bio-Oss and Cerasorb.

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Abstract  

A unique procedure permitting the determination of90Sr and actinides in the same protion of sample, with good chemical yields of all analytes, is presented. Animal tissue samples containing bone are ashed, spiked with2 3 2U,2 4 2Pu,2 4 3Am and8 5Sr and solubilized. The actinides and strontium are gathered and separated by a series of coprecipitations with, cerium hydroxide and cerium fluoride. Actinide separation and determination and purification and determination of90Sr are accomplished by a combination of several well-known procedures. The laboratory method consistently results in high chemical yields of all the analytes and overcomes interferences from phosphates and calcium.

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Farmland ponds represent habitats with a high conservation value that make a significant contribution to regional biodiversity. Understanding the influence of plant species composition and environmental variables in driving variations in animal species composition in ponds is an important issue in the fields of ecological research and conservation biology. Using variance partitioning techniques to quantify independent effects, we examined how plant species composition, local-landscape configuration and physicochemical variables interact in influencing aquatic insect and amphibian community composition. The ponds investigated in this study were located in the Site of Community Importance — Special Protected Area (Natura 2000 Network) “Monte Labbro — Alta Valle dell’Albegna” (Tuscany, central Italy). Our results showed that: (i) plant community composition (such as Carex hirta, Glicerya fluitans, Potamogeton natans, Typha latifolia) is a good predictor for amphibian but not for aquatic insect species composition; (ii) aquatic insect species composition was more strongly affected by the landscape context, whereas for amphibians the local characteristics of the ponds were determining; (iii) the physicochemical context is a poor predictor for these animal taxa; (iv) lastly, and notably, the explanatory variables explained a high proportion of the total variation in amphibian and aquatic insect species composition. Our results have important implications with respect to the creation of new ponds, which should preferentially take place close to semi-natural grasslands and other wetlands, in order to maintain greater connectivity, and away from urban areas. Moreover, larger ponds are preferable for the preservation of pond biodiversity. The management and conservation of ponds is necessary to ensure the protection of habitats, the survival of individual species and overall pond biodiversity.

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Abstract  

Within the framework of the Protection of the Environment programme of the JRC-Ispra of the European Community, research on trace metal exposure and health effects is concerned primarily with the toxicological assessment of present levels of trace metals in the tissues of exposed and unexposed populations. Main activities are: (1) microdetermination of trace elements in human tissues in order to generate an accurate and reliable data base on the levels and biochemical forms of trace metals in differently exposed humans; (2) metabolism and biochemical mechanisms involving trace metals to assess the toxicological significance of the current levels of the elements in the human body. Few selected applications related to the different steps of the biochemical toxicology research are shown. They concern the long-term behaviour of trace metals at the target tissues of laboratory animals, the biological monitoring of vanadium in workers during maintenance operations at an oil fired power plant for energy production, and the biochemical mechanism of methylation of arsenic in vivo.

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