In 1998, a permeable reactive barrier system was installed at the Atomic Energy of Canada Ltd. (AECL) Chalk River Laboratories in Chalk River, Ontario, to prevent the discharge of a 90Sr plume into a nearby swamp. The system known as the “Wall and Curtain” contains clinoptilolite, a zeolite, as a reactive material to sorb 90Sr. The overall objective of this study was to provide refined estimates of the efficiency and longevity of the system. To better understand the flow in the aquifer and through the Wall and Curtain, a detailed physical field characterization of the site was performed. Borehole-dilution tests were performed in 19 mm (¾ inch) drive-point piezometers. The results indicate that the Wall and Curtain system intercepted deeper, contaminated groundwater as intended. Hydraulic conductivities (K) determined through slug tests indicate that the aquifer was relatively homogeneous. Average linear groundwater velocities determined through borehole dilution compared well with velocities determined through the Darcy equation based on slug-test K estimates. The measurements from the field study were used to develop a three dimensional physical flow model. The numerical computer code HydroGeoSphere was used to provide an approximate representation of groundwater flow in the aquifer and through the Wall and Curtain. The model was calibrated by comparing simulated and observed hydraulic head values across the site. The model showed good agreement with the observed heads and acceptable agreement with the field estimates of groundwater velocities. A detailed geochemical characterization of the aquifer and the reactive material, clinoptilolite, was performed through field and laboratory work. Pore-water samples were taken from multiple locations in the aquifer. Solid and pore-water samples from the reactive material were used to determine distribution coefficients for 90Sr and competing cations. Sequential leach tests were performed on small amounts of the radioactive solid samples. Results indicate that the system was highly efficient in treating an average mass flux of > 17,000 Bq/m2day-1. The leading edge of the plume was found to have only reached 40 cm into the 2 m thick Curtain of clinoptilolite after nearly 14 years of operation. The reactive material readily sorbed 90Sr, with a distribution coefficient of > 76,000 mL/g for beta activity. Kinetically controlled ion exchange was the main mechanism of sorption onto the clinoptilolite for most cations. The results indicate that the system was highly efficient. Reactive transport models of the site using two different numerical codes, HydroGeoSphere and MIN3P, were constructed to provide refined estimates of the longevity of the system. The model constructed in HydroGeoSphere included five solutes. Zoned distribution coefficients were specified for the transported solutes. In MIN3P, only the reactive material was used as a model domain. Typical concentrations of the plume were specified. Ion exchange was considered in the simulation, as well as radioactive decay of Sr. An updated version of MIN3P was used which also considers kinetic sorption of Sr. Longevity estimates of the different simulations ranged between 30 years and over 200 years for the Wall and Curtain system. Based on field and laboratory experiments, longevity estimates of 80 years to 100 years seemed more reasonable. Results of the numerical simulation indicate that by that time, the system would have remediated 1200 MBq of 90Sr. Continuous monitoring of the outflow will ensure that the time-to-replacement of the system will be met.

In 1998, a permeable reactive barrier system was installed at the Atomic Energy of Canada Ltd. (AECL) Chalk River Laboratories in Chalk River, Ontario, to prevent the discharge of a 90Sr plume into a nearby swamp. The system known as the “Wall and Curtain” contains clinoptilolite, a zeolite, as a reactive material to sorb 90Sr. The overall objective of this study was to provide refined estimates of the efficiency and longevity of the system. To better understand the flow in the aquifer and through the Wall and Curtain, a detailed physical field characterization of the site was performed. Borehole-dilution tests were performed in 19 mm (¾ inch) drive-point piezometers. The results indicate that the Wall and Curtain system intercepted deeper, contaminated groundwater as intended. Hydraulic conductivities (K) determined through slug tests indicate that the aquifer was relatively homogeneous. Average linear groundwater velocities determined through borehole dilution compared well with velocities determined through the Darcy equation based on slug-test K estimates. The measurements from the field study were used to develop a three dimensional physical flow model. The numerical computer code HydroGeoSphere was used to provide an approximate representation of groundwater flow in the aquifer and through the Wall and Curtain. The model was calibrated by comparing simulated and observed hydraulic head values across the site. The model showed good agreement with the observed heads and acceptable agreement with the field estimates of groundwater velocities. A detailed geochemical characterization of the aquifer and the reactive material, clinoptilolite, was performed through field and laboratory work. Pore-water samples were taken from multiple locations in the aquifer. Solid and pore-water samples from the reactive material were used to determine distribution coefficients for 90Sr and competing cations. Sequential leach tests were performed on small amounts of the radioactive solid samples. Results indicate that the system was highly efficient in treating an average mass flux of > 17,000 Bq/m2day-1. The leading edge of the plume was found to have only reached 40 cm into the 2 m thick Curtain of clinoptilolite after nearly 14 years of operation. The reactive material readily sorbed 90Sr, with a distribution coefficient of > 76,000 mL/g for beta activity. Kinetically controlled ion exchange was the main mechanism of sorption onto the clinoptilolite for most cations. The results indicate that the system was highly efficient. Reactive transport models of the site using two different numerical codes, HydroGeoSphere and MIN3P, were constructed to provide refined estimates of the longevity of the system. The model constructed in HydroGeoSphere included five solutes. Zoned distribution coefficients were specified for the transported solutes. In MIN3P, only the reactive material was used as a model domain. Typical concentrations of the plume were specified. Ion exchange was considered in the simulation, as well as radioactive decay of Sr. An updated version of MIN3P was used which also considers kinetic sorption of Sr. Longevity estimates of the different simulations ranged between 30 years and over 200 years for the Wall and Curtain system. Based on field and laboratory experiments, longevity estimates of 80 years to 100 years seemed more reasonable. Results of the numerical simulation indicate that by that time, the system would have remediated 1200 MBq of 90Sr. Continuous monitoring of the outflow will ensure that the time-to-replacement of the system will be met.

In this dissertation is analysed the transfer of artificial radionuclides (137Cs and 90Sr) from soil to tree. The main goal of this work – to estimate specific activi-ties of 137Cs and 90Sr in selected trees, investigate the peculiarities of these ra-dionuclides distribution in trees, suggest the methodology for estimation of the transfer of radionuclides from soil to tree in tree wood by chemical analog in soil under the tree crown, and to do the forecast of transfer of radionuclides in sys-tem “soil–tree” by the most relevant models. The main tasks solved in this dissertation are following: to do the radiomet-ric, radiochemical and biological affections researches of selected pines, evalu-ate the specific activity and concentration in collected samples of investigated radionuclides and their chemical analogs, apperciate the transfer of 137Cs and 90Sr from soil to tree and analyse peculiarities of this process by soil radioactive pollution and plants growing peculiarities; to modelling the spread of 137Cs and 90Sr distribution in system “soil–plant”, the accumulation of these radionuclides in tree and internal doses. This dissertation consists of introduction, five chapters, the main conclusion and recommendation, bibliography and list of author publications. In the introduction it is discussed the investigated problem, actualities of work, object of research, scientific novelty and practical significant of this dis-sertation, protective hypotheses. Additionally it is... [to full text] / Disertacijoje nagrinėjama dirbtinės kilmės radionuklidų (137Cs ir 90Sr) per-naša iš dirvožemio į medį. Pagrindinis šio darbo uždavinys – nustatyti 137Cs ir 90Sr savituosius aktyvumus tyrimui parinktuose medžiuose bei įvertinti šių ra-dionuklidų pasiskirstymo juose ypatumus, pasiūlyti metodiką radionuklido per-našos iš dirvožemio į medį vertinimui pagal radionuklido cheminį analogą dir-vožemyje po medžio laja, atlikti radionuklido pernašos iš dirvožemio į medį prognozę, parinkus tinkamiausius modelius. Šiame darbe sprendžiami tokie pagrindiniai uždaviniai: atlikti medžių sandų radiometrinius, radiocheminius ir pušų biologinio pažeistumo tyrimus; įvertinti tiriamųjų radionuklidų ir jų stabiliųjų cheminių analogų savituosius aktyvumus bandiniuose; įvertinti 137Cs ir 90Sr pernašos iš dirvožemio į medžius ir pasiskirs-tymo juose ypatumus, atsižvelgiant į dirvožemio radioaktyviąją užtaršą ir augalo vystymosi ypatumus; modeliuoti 137Cs ir 90Sr migracijos sistemoje „dirvožemis–medis“ sklaidą, įvertinti radionuklidų sukauptą augale kiekį, modeliuoti augalo patiriamą vidinę apšvitą. Disertaciją sudaro įvadas, penki skyriai, bendrosios išvados, rekomendaci-jos, naudotos literatūros ir autorės publikacijų sąrašai. Įvadiniame skyriuje aptariama tiriamoji problema, darbo aktualumas, apra-šomas tyrimų objektas, darbo mokslinis naujumas, darbo rezultatų praktinė reikšmė, ginamieji teiginiai. Pristatomos disertacijos tema autorės paskelbtos publikacijos, pranešimai, disertacijos struktūra... [toliau žr. visą tekstą]

Os aplicadores de 90Sr+90Y utilizados no Brasil em betaterapia para prevenção de quelóide e pterígio são importados e suas características dosimétricas são obtidas através de tabelas e manuais dos fabricantes apenas de forma ilustrativa pelos fabricantes. A rotina exaustiva dos profissionais de física médica nos serviços de radioterapia muitas vezes não viabiliza a realização de procedimentos para confirmação destes parâmetros. Este trabalho apresenta o desenvolvimento de uma metodologia para dosimetria de aplicadores de betaterapia de 90Sr+90Y. O software MCNP5 que é baseado no método de Monte Carlo foi utilizado para simulação das curvas de porcentagem de dose profunda e perfis de distribuição de dose produzidos por estes aplicadores. As medidas experimentais da atenuação da radiação, perfil radial e axial, foram realizadas com uma mini-câmara de extrapolação, dosímetros termoluminescentes e filmes radiocrômicos. Os resultados das medidas experimentais foram comparados com os valores simulados. Ambas as curvas de porcentagem de dose profunda e os perfis de distribuição de dose radiais, teóricos e experimentais, apresentaram boa concordância, o que pode validar o uso do software MCNP5 para estas simulações, reforçando a viabilidade do uso deste método nos procedimentos de dosimetria destas fontes emissoras de radiação beta. / The 90Sr+90Y applicators, used in Brazil betatherapy for prevention of keloids and pterigium, are imported and their dosimetric features are obtained through charts and manuals provided only in an illustrated form by the manufacturers. The exhaustive routine of the medical physicists in the clinic often do not make possible the accomplishment of procedures for the confirmation of these parameters. This work presents the development of a methodology for the dosimetry of 90Sr+90Y betatherapy applicators. The MCNP5 software that is based on the Monte Carlo method was used for the simulation of the percentage depth dose curves and dose distribution profiles produced by these applicators. The experimental measurements of the radial and axial radiation attenuation, have been done with a mini-extrapolation chamber, thermoluminescent dosimeters and radiographic films. The experimental results have been compared with the simulated values. Both percentage depth dose curves and the radial dose profiles, the theoretical and the experimental ones, have presented good agreement, which may validate the use of the MCNP5 software for these simulations, confirming the viability of the usage of this method in procedures of beta emitter sources dosimetry.

Os aplicadores de 90Sr+90Y utilizados no Brasil em betaterapia para prevenção de quelóide e pterígio são importados e suas características dosimétricas são obtidas através de tabelas e manuais dos fabricantes apenas de forma ilustrativa pelos fabricantes. A rotina exaustiva dos profissionais de física médica nos serviços de radioterapia muitas vezes não viabiliza a realização de procedimentos para confirmação destes parâmetros. Este trabalho apresenta o desenvolvimento de uma metodologia para dosimetria de aplicadores de betaterapia de 90Sr+90Y. O software MCNP5 que é baseado no método de Monte Carlo foi utilizado para simulação das curvas de porcentagem de dose profunda e perfis de distribuição de dose produzidos por estes aplicadores. As medidas experimentais da atenuação da radiação, perfil radial e axial, foram realizadas com uma mini-câmara de extrapolação, dosímetros termoluminescentes e filmes radiocrômicos. Os resultados das medidas experimentais foram comparados com os valores simulados. Ambas as curvas de porcentagem de dose profunda e os perfis de distribuição de dose radiais, teóricos e experimentais, apresentaram boa concordância, o que pode validar o uso do software MCNP5 para estas simulações, reforçando a viabilidade do uso deste método nos procedimentos de dosimetria destas fontes emissoras de radiação beta. / The 90Sr+90Y applicators, used in Brazil betatherapy for prevention of keloids and pterigium, are imported and their dosimetric features are obtained through charts and manuals provided only in an illustrated form by the manufacturers. The exhaustive routine of the medical physicists in the clinic often do not make possible the accomplishment of procedures for the confirmation of these parameters. This work presents the development of a methodology for the dosimetry of 90Sr+90Y betatherapy applicators. The MCNP5 software that is based on the Monte Carlo method was used for the simulation of the percentage depth dose curves and dose distribution profiles produced by these applicators. The experimental measurements of the radial and axial radiation attenuation, have been done with a mini-extrapolation chamber, thermoluminescent dosimeters and radiographic films. The experimental results have been compared with the simulated values. Both percentage depth dose curves and the radial dose profiles, the theoretical and the experimental ones, have presented good agreement, which may validate the use of the MCNP5 software for these simulations, confirming the viability of the usage of this method in procedures of beta emitter sources dosimetry.

90Y (T1/2 = 2,67 dias; Eβmáx = 2,28 MeV) é um radionuclídeo com eficácia estabelecida para diversas terapias de câncer, marcando biomoléculas e no tratamento da radiosinovectomia. Devido às suas propriedades nucleares, é obtido através do decaimento do 90Sr (T1/2 = 28 anos), na forma de um gerador. Vários tipos de geradores de 90Sr/90Y foram desenvolvidos, e os mais empregados são os que usam resinas de troca catiônica, onde Sr e Y são adsorvidos e 90Y é seletivamente eluído com acetato ou EDTA. A desvantagem deste tipo de gerador é a radiólise, que degrada o seu uso. O gerador eletroquímico é uma solução proposta devido ao fato de não haver efeitos significativos da radiação sobre o próprio gerador. Neste conceito, a diferença entre os potenciais eletroquímicos dos elementos Y e Sr é utilizada para se obter uma rápida separação do 90Y do 90Sr. A produção de 90Y via formação de colóides é o método mais simples para a separação, baseando-se na formação de colóides de Y em pH altamente alcalino, podendo ser filtrado e separado do Sr, sendo posteriormente dissolvido em HCl. O objetivo deste trabalho consistiu no desenvolvimento de tecnologias para o preparo de geradores de 90Sr/90Y, onde foram desenvolvidos três tecnologias, a saber: geradores do tipo coluna utilizando resinas catiônicas, geradores via formação de colóides e geradores eletroquímicos. Foram também avaliadas metodologias para o controle de qualidade radionuclídico do 90Y dos geradores desenvolvidos: cintilação líquida, identidade radionuclídica, cromatografia por extração em papel (EPC) utilizando complexantes para 90Y e técnica por Espectrometria de Emissão Ótica com Plasma Indutivamente Acoplado (ICPOES). Os resultados mostraram que os geradores utilizando resinas catiônicas obtiveram os melhores resultados em relação ao rendimento e eficiência (~ 83%) de eluição, reprodutibilidade e a pureza radionuclídica. O gerador eletroquímico mostrou um potencial para o desenvolvimento, tendo a vantagem de não sofrer os efeitos da radiólise do par 90Sr/90Y, como acontece com a resina. Das metodologias de controle qualidade radionuclídica estudadas, uma comparação e avaliação mostrou que a EPC é muito sensível e permite a avaliação praticamente instantânea da qualidade do 90Y eluído dos geradores. / 90Y (T1/2 = 2,67 d; Eβmáx = 2,28 MeV) is a radionuclide with efficacy established for various cancer therapies, labeling biomolecules and treating of radiosinovectomy. Due to its nuclear properties, is obtained through the decay of 90Sr T1/2 = 28 y in the form of a generator. Several types of 90Sr/90Y generators were developed, and the most employed are the cation exchange resins, where Sr and Y are adsorbed and 90Y is selectively eluted with acetate or EDTA. The disadvantage of this type of generator is the radiolysis, which degrades its use. The electrochemical generator is a proposed solution because there is no significant effect of radiation. In this concept, the difference between the electrochemical potentials of the elements Sr and Y is used to obtain a rapid separation of 90Y from 90Sr. The production of 90Y via colloid formation is the simplest method for the separation, based on the colloid formation of Y in high alkaline pH, which can be filtered and separated from Sr, and subsequently dissolved in HCl. The objective of this work was the development of technologies for the preparation of 90Sr/90Y generators, and three technologies were developed: generators using cation resins columns, generators through colloid formation and electrochemical generators. Radionuclidic quality control of 90Y was also evaluated by liquid scintillation, radionuclide identity, extraction paper chromatography (EPC) using complexing agents for 90Y and by Optical Emission Spectrometry with Inductively Coupled Plasma (ICP-OES). The results showed that generators using cation resins have the best results related to the elution efficiency (~83%), the reproducibility and radionuclidic purity. The electrochemical generator showed a potential for development, having the advantage of not suffering the effects of radiolysis of the pair 90Sr/90Y as the resin. A comparison and evaluation of the methods of the radionuclidic quality control showed that the EPC is very sensitive and allows for virtually instantaneous assessment of the quality of 90Y generator.

90Y (T1/2 = 2,67 dias; Eβmáx = 2,28 MeV) é um radionuclídeo com eficácia estabelecida para diversas terapias de câncer, marcando biomoléculas e no tratamento da radiosinovectomia. Devido às suas propriedades nucleares, é obtido através do decaimento do 90Sr (T1/2 = 28 anos), na forma de um gerador. Vários tipos de geradores de 90Sr/90Y foram desenvolvidos, e os mais empregados são os que usam resinas de troca catiônica, onde Sr e Y são adsorvidos e 90Y é seletivamente eluído com acetato ou EDTA. A desvantagem deste tipo de gerador é a radiólise, que degrada o seu uso. O gerador eletroquímico é uma solução proposta devido ao fato de não haver efeitos significativos da radiação sobre o próprio gerador. Neste conceito, a diferença entre os potenciais eletroquímicos dos elementos Y e Sr é utilizada para se obter uma rápida separação do 90Y do 90Sr. A produção de 90Y via formação de colóides é o método mais simples para a separação, baseando-se na formação de colóides de Y em pH altamente alcalino, podendo ser filtrado e separado do Sr, sendo posteriormente dissolvido em HCl. O objetivo deste trabalho consistiu no desenvolvimento de tecnologias para o preparo de geradores de 90Sr/90Y, onde foram desenvolvidos três tecnologias, a saber: geradores do tipo coluna utilizando resinas catiônicas, geradores via formação de colóides e geradores eletroquímicos. Foram também avaliadas metodologias para o controle de qualidade radionuclídico do 90Y dos geradores desenvolvidos: cintilação líquida, identidade radionuclídica, cromatografia por extração em papel (EPC) utilizando complexantes para 90Y e técnica por Espectrometria de Emissão Ótica com Plasma Indutivamente Acoplado (ICPOES). Os resultados mostraram que os geradores utilizando resinas catiônicas obtiveram os melhores resultados em relação ao rendimento e eficiência (~ 83%) de eluição, reprodutibilidade e a pureza radionuclídica. O gerador eletroquímico mostrou um potencial para o desenvolvimento, tendo a vantagem de não sofrer os efeitos da radiólise do par 90Sr/90Y, como acontece com a resina. Das metodologias de controle qualidade radionuclídica estudadas, uma comparação e avaliação mostrou que a EPC é muito sensível e permite a avaliação praticamente instantânea da qualidade do 90Y eluído dos geradores. / 90Y (T1/2 = 2,67 d; Eβmáx = 2,28 MeV) is a radionuclide with efficacy established for various cancer therapies, labeling biomolecules and treating of radiosinovectomy. Due to its nuclear properties, is obtained through the decay of 90Sr T1/2 = 28 y in the form of a generator. Several types of 90Sr/90Y generators were developed, and the most employed are the cation exchange resins, where Sr and Y are adsorbed and 90Y is selectively eluted with acetate or EDTA. The disadvantage of this type of generator is the radiolysis, which degrades its use. The electrochemical generator is a proposed solution because there is no significant effect of radiation. In this concept, the difference between the electrochemical potentials of the elements Sr and Y is used to obtain a rapid separation of 90Y from 90Sr. The production of 90Y via colloid formation is the simplest method for the separation, based on the colloid formation of Y in high alkaline pH, which can be filtered and separated from Sr, and subsequently dissolved in HCl. The objective of this work was the development of technologies for the preparation of 90Sr/90Y generators, and three technologies were developed: generators using cation resins columns, generators through colloid formation and electrochemical generators. Radionuclidic quality control of 90Y was also evaluated by liquid scintillation, radionuclide identity, extraction paper chromatography (EPC) using complexing agents for 90Y and by Optical Emission Spectrometry with Inductively Coupled Plasma (ICP-OES). The results showed that generators using cation resins have the best results related to the elution efficiency (~83%), the reproducibility and radionuclidic purity. The electrochemical generator showed a potential for development, having the advantage of not suffering the effects of radiolysis of the pair 90Sr/90Y as the resin. A comparison and evaluation of the methods of the radionuclidic quality control showed that the EPC is very sensitive and allows for virtually instantaneous assessment of the quality of 90Y generator.

<p>U disertaciji je izvr&scaron;ena optimizacija detektorskog IZ&nbsp;&nbsp; sistema Quantulus 1220^TM radi razvoja metoda za određivanje pojedinačnih radionuklida ³H,²²²Rn i⁹⁰Sr, kao i ukupne alfa/beta aktivnosti u vodama. Predstavljeni su eksperimenti u svrhu kalibracije sistema, istraživanja uticaja relevantnih parametara na rezultate određivanja aktivnosti alfa i beta emitera, i pode&scaron;avanja optimalnih vrednosti ovih parametara.&nbsp;Posebna pažnja je posvećena variranju&nbsp; PSA diskriminatora, odnosno pode&scaron;avanju analizatora oblika impulsa na optimalnu vrednost u svrhu optimalnog razdvajanja alfa od beta događaja, kao i ispitivanju efekata prigu&scaron;enja u uzorcima i metodama&nbsp;njihove korekcije.&nbsp; Predstavljene razvijene metode su brze, efikasne i jednostavne, &scaron;to je naročito važno u slučaju radijacionog akcidenta, kada je potrebno brzo odrediti sadržaj radionuklida u&nbsp; uzorcima vode, a njihova validnost je pokazana u okviru međunarodnih<br />i međulaboratorijskih interkomparacija.</p> / <p>Dissertation involves optimization of detector AB&nbsp;&nbsp; system&nbsp; Quantulus 1220^TM for development of methods for determination of individual radionuclides ³H, ²²²Rn and ⁹⁰Sr, as well as gross alpha/beta activity in waters. Presented experiments had purpose of calibration of the system,&nbsp; investigation&nbsp; of&nbsp; relevant parameters&nbsp; influence&nbsp; on&nbsp; activity&nbsp; measurements&nbsp; of alpha and beta emitters, as well as&nbsp; setting the optimum values of&nbsp; these parameters. Special attention&nbsp; was devoted to&nbsp; PSA&nbsp; discriminator value&nbsp; setting, i.e. adjusting the pulse shape analyzer level at optimum value for an optimal separation of alpha from beta events, as well as testing the effects of quenching in the samples and methods for quench&nbsp; correction. Presented developed methods are fast, efficient and simple, which is especially important in the case of a radiation accident, when there is a need to quickly determine the content of radionuclides in water samples, and their validity has been demonstrated within the framework of international and inter-laboratory&nbsp; ntercomparison measurements.</p>

It was being exploratored radiation pollution of fish living in water-cooling basin of Ignalina Nuclear Power Plant (NPP) in master's work. The objectives of work. NPP water-cooling basin's fish. The purpose of work was to estimate fish (Rutilus rutilus ( L.), Abramis brama ( L.), Esox lucius ( L.) and Perca fluviatilis ( L.)) contamination degree with macrobiotic radioisotopes cesium ( 137Cs) and strontium ( 90Sr) of Ignalina Nuclear Power Plant ( NPP) water cooling basin, to point up estimated radio-pollution concentrations dependence from fish capturing period of year, their (fish) varietal particularity, nutritional mode of fish life and compare with fish contamination by macrobiotic radioisotopes in other Lithuanian waters. Methods of work. Gama spectral analysis to estimate 137Cs levels in foodstaffs; 90Sr method estimation in foodstaffs and environmental samples by method of Tcherenkov radiation. The experiment was accomplished in the Laboratory of Environmental Protection – the subdivision of Ignalina NPP in 2004-2005. Samples of fish were delivered for the investigations by three times a year ( by 20 kg for every time (month); by 5 kg of different kind; totally 60 kg). It was being applied that method for statistical evaluation of secured data - calculable marks evaluation of secured results. All findings are on 95 % reliability level. The results of investigations showed, that larger specific activity of ( 137Cs) has been found in Esox lucius ( L.) and Perca... [to full text]

La présente étude s’inscrit dans le contexte post-Fukushima et avait pour objectif la mise en place d’une méthode d’analyse pour identifier et quantifier, rapidement, des radionucléides émetteurs alpha et bêta, en situation post-accidentelle, dans les échantillons de l’environnement. La première étape de l’étude a permis de dresser la liste des radio-isotopes émetteurs alpha et bêta susceptibles d’être rejetés dans l’environnement suite à un accident nucléaire. Dans une deuxième étape, un protocole d’analyse rapide a été développé pour 17 radio-isotopes de U, Th, Pu, Am, Np et Sr. L’objectif était d’automatiser l’étape de séparation radiochimique et de la coupler à la mesure. La séparation est réalisée en employant des colonnes contenant les résines d’extraction, TEVA®, TRU et Sr. La mesure est effectuée par ICP-MS (spectrométrie de masse à plasma induit) et dans certains cas par compteur proportionnel à gaz pour quantifier le radiostrontium (89Sr et 90Sr). D’excellentes performances analytiques ont été obtenues, lors de la mesure hors-ligne, pour des échantillons d’eaux (robinet, rivière et mer) et solides (sols et filtres d’aérosols), après une minéralisation par four à micro-ondes ou par fusion alcaline suivie d’une co-précipitation avec Ca3(PO4)2. Ces performances sont caractérisées par des rendements de récupération compris entre 70 % et 100 % et des écarts types entre 5 % et 10 %. Le protocole de séparation a été ensuite automatisé et transposé en mode couplage en ligne avec l’ICP-MS. Les paramètres opératoires ont été optimisés avec un plan d’expériences, défini et exploité avec le logiciel Minitab®. Après optimisation du protocole, l’automatisation et le couplage de la séparation permettent de quantifier rapidement, en 1,5 h par échantillon, U, Th, Pu, Am, Np et Sr et de gagner un facteur 20 sur les limites de détection des radio-isotopes artificiels. / The present study follows the Fukushima power plant accident and aimed to develop an analytical method to achieve, during an emergency situation, a rapid identification and quantification of alpha and beta emitters in environmental samples. The first step of this study allowed us to list the alpha and beta emitters which can be released in the environment in case of a nuclear accident. The second step aimed towards the development of a rapid analysis method to quantify 17 radionuclides of U, Th, Pu, Am, Np and Sr. The main objective was the automation of the radiochemical separation step and its coupling for the measurement. The separation is performed using columns containing extraction resins, namely TEVA®, TRU and Sr. The measurement is performed using an ICP-MS (inductively coupled plasma mass spectrometry) and in some cases a gas proportional counter to quantify radiostrontium (89Sr and 90Sr). Excellent figures of merit were obtained, off line, with water (tap, river and sea water) and solid matrices (soil and aerosol filters), after a micro-wave digestion or an alkaline fusion dissolution followed by a Ca3(PO4)2 coprecipitation. The proposed analytical strategy showed yields between 70 % and 100 % and standard deviations between 5 % and 10 %. The newly developed separation method was then automated and coupled on-line to ICP-MS. The operating parameters were optimized using a design of experiments and the results were processed with Minitab®. The optimized automated separation coupled on-line to the ICP-MS allows the rapid quantification, in 1.5 h per sample, of U, Th, Pu, Am, Np and Sr with detection limits gain as high as 20 times for artificial radionuclides.