In surface soils, the native physical and chemical properties of the abiotic components control most of the sorption-desorption processes. Moreover, micro-organisms may significantly modify the speciation of trace elements and/or radionuclides and subsequently determine their fate, to a large extent. Micro-organisms, mainly bacteria and fungi, develop many strategies that may affect indirectly or directly the behaviour of trace elements. Due to their activity, changes in the pore-water composition, e.g. pH, redox-potential, may occur in relation with organic acid production or solid phase alteration, reduction or oxidation of metallic oxi-hydroxides, and mineralization of organo-metallic complexes. Micro-organisms may also directly modify the speciation of radionuclides as a result of bio-accumulation in living cells, biosorption on cellular components, direct reduction or oxidation, biomethylation, etc. Each one of these microbial processes may either increase or decrease radionuclide mobility, depending on the element, the soil reactivity and the environmental conditions. The resulting effect of these processes is still poorly known. This literature review intends to present a comprehensive overview of the role of micro-organisms on radionuclide mobility. It aims at classifying these elements, regarding to their potential sensitivity to these microbial processes. It summarizes the theoretical effect of these mechanisms, resulting in a potential increase or decrease of the solid-liquid distribution. The environmental significance of such processes for various biogeochemical radionuclides cycles still remains to be confirmed by experiments. (This study is part of a research program supported by Andra).

Quelles sont les valeurs qui caractérisent sur le territoire français les rayonnements ionisants et les radionucléides d'origine naturelle ? Comment distinguer dans le résultat d'une mesure la part qui résulte éventuellement d'une activité humaine ? Afin d'essayer de répondre à ces questions, un questionnaire a été adressé aux différents organismes qui effectuent en France des mesures de radioactivité dans l'environnement. Les informations mentionnées dans cette étude se rapportent exclusivement à des observations faites dans l'environnement à l'extérieur des bâtiments et du périmètre des installations nucléaires de base (INB). En outre, elles ne concernent, sauf cas particuliers signalés, que des mesures de rayonnements ou de radioéléments d'origine naturelle dont les résultats n'ont pas été perturbés par l'action de l'homme. L'enquête montre la difficulté actuelle de dresser en France un bilan exhaustif des connaissances acquises concernant les caractéristiques du bruit de fond radioactif d'origine naturelle dans l'environnement. Aujourd'hui en France, dans le domaine de la radioactivité naturelle, les efforts consentis manquent de coordination et d'orientation vers certaines priorités. À ce titre, les mesures des 238U et 232Th précurseurs des 226Ra et 228Ra, des descendants solides émetteurs alpha du radon (par la mesure des EAP du 222Rn et 220Rn), des émetteurs gamma post émanation (214Pb, 214Bi, 212Pb), du 210Pb, 210Po et du 14C doivent être privilégiées.

The Rhône watershed extends over almost one hundred thousands square kilometers, i.e. one fifth of the metropolitan French territory. The Rhône is the major River entering the Western Mediterranean Sea as it generates the main source of sediments and freshwater (50%) to the sea, with an average water discharge of 1700 m3 s-1. The River input affects primary production significantly in the north-western Mediterranean area and plays a leading role on the marine ecosystem functioning in the whole Gulf of Lion. Almost twenty nuclear reactors are situated along the Rhône valley, representing Europe’s biggest concentration of nuclear power plants. Down flow all these installations the spent fuel reprocessing plant of Marcoule released over many years most of the liquid radioactive wastes including plutonium isotopes in the Rhône river. Artificial radionuclides also originate from the weathering of the catchment basin labeled by both the global and the Chernobyl accident atmospheric fallout. These radioactive inputs have led to a permanent contamination of the Rhône river waters. Long-term chronological series of artificial radionuclide activities within the waters at the lower reaches of the Rhône river were acquired from 1979 to 2002. These data give evidence for various radioecological responses of the aquatic system over years. Based on these observations several major radioecological sensitivity factors for river waters are identified.

The protection of biota from ionising radiations needs reliable predictions of radionuclide dynamics in wild animals. Data specific for many wild animal - radionuclide combinations is lacking and a number of approaches including allometry have been proposed to address this. However, for 14C and 3H, which are integral components of animal tissues and their diets, a different approach is needed. Here we propose a metabolically based model which can be parameterised predominantly on the basis of published metabolic data. We begin with a metabolic definition of the 14C and OBT loss rate (assumed to be the same) from the whole body and specific organs. The mammalian body is conceptually partitioned into compartments (body water, viscera, adipose, muscle, blood and remainder) and a simple model defined using net maintenance and growth needs of mammals. The model is tested with data from studies using rats and sheep. It provides a reliable prediction for whole body and muscle activity concentrations without the requirement for any calibration specific to 3H and 14C. Predictions from the model for representative wild mammals) are presented. Potential developments of a metabolic model for birds and the application of our work to human foodchain modelling are also discussed.

New data on abundance and isotope composition of “hot” and active particles in alluvial soils and sediments of the Yenisei river (Krasnoyarsk region, Russia), located in a near influence zone of the Krasnoyarsk Mining and Chemical Processing Plant (KMCPP), are presented in this study. On a set of gamma-emitting radioisotopes all “hot” particles can be divided on three groups: 1. monoisotopic (137Cs, 60Co); 2. two-isotopic (137Cs and 134Cs); 3. polyisotopic (137Cs, 134Cs, 60Co, 154Eu, 155Eu and 241Am). Very significant is the absence of 152Eu in all polyisotopic particles whereas in soils this isotope is often predominant. The active particles are presented by the several polyisotopic types, containing: 1. 154Eu, 155Eu, 137Cs, 60Co and 241Am; 2. 154Eu, 155Eu, 137Cs and 241Am; 3. 152Eu, 154Eu, 155Eu, 60Co and 241Am and monoisotopic (60Co and 137Cs). Presence of the active particles containing all isotopes, except of 137Cs, and particles without 152Eu and 60Co is interesting. Some active particles due to their set of radioisotopes can be referred to the finely dispersed fragments of the “hot” particles. However, the majority of them have the nature distinct from the “hot” particles.

Naturally occurring radionuclides in building materials are sources of external and internal exposure in dwellings. External radiation exposure is caused by the gamma radiation originating from members of uranium and thorium decay chain and from 40K. Internal radiation exposure, mainly affecting the respiratory tract, is due to the short-lived daughter products of radon which are exhaled from building materials into room air. The objective of this study is to measure the radon exhalation rates from zircon materials, flours and sands, used as raw materials in the porous fired tiles body and from the final products (porcelain tiles usually commercialized in Italy). The radon exhalation rates for the zircon flours and sands ranged from 0.17 to 1.9 Bq kg-1 h-1, and from 0.090 to 0.20 Bq kg-1 h-1; 222Rn exhalation rates for most of the porcelain stoneware tiles are near or below the minimum detectable limit (LLD) of 0.0004 Bq kg-1 h-1.

A radiation transport code based on a Monte Carlo tool is used to simulate a protontherapy beamline designed to treat paediatric patients with intracranial tumours. Thetreatments are performed using the IBA gantry at the Proton Therapy Centre of the InstitutCurie. The treatment is undertaken at 178.16 MeV using the double scattering technique.The aim of this study is to present the Monte Carlo model of the transported proton beam,beamline and treatment room, as well as the experimental validation of the proton dosedistributions calculated by this model. The beamline components and the treatment room areaccurately modelled using the Monte Carlo code MCNPX. The proton source at the beamlineentrance is defined on the basis of IBA data, measurements and calculations. Measured andcalculated relative proton dose distributions in a water phantom are compared for thevalidation. Depth dose profiles, including pristine Bragg peaks and a spread–out Braggpeak, and lateral dose profiles are studied. A general good agreement was found betweencalculated and measured distributions with discrepancies of less than 2 mm. Relativeproton dose distributions are therefore considered to be correctly described by oursimulated geometry and proton source parameters. The Monte Carlo simulation will be usedsubsequently for radiation protection purposes: calculation of secondary neutron dosesreceived by treated patients of different ages.

One of the most serious problems occurring during coal extraction in Upper Silesia in Poland is caused by waters with very high salinity. These waters often contain also high concentrations of natural radionuclides, mainly 226Ra from uranium series and 228Ra from thorium series. At least 70% of the total amount of radium carried by this waters remains nowadays in underground galleries as radioactive deposits. But, during the period of the most extensive coal extraction up to 225 MBq of 226Ra and 400 MBq of 228Ra were released daily into surface along with the other mine effluents. As a result of discharge of radium-bearing waters into settling ponds and later into rivers a significant increase of radium concentration in bottom sediments has been observed. Sometimes there is also a contamination of river beds, soils and biota. The paper describes results of investigation of waters and sediments with enhanced natural radioactivity, that occur in settling ponds, where mine waters have been dumped. Measurements of different factors of radiological hazard were made, such as radium content in the soil from ponds' banks, variations of gamma radiation background and radon exhalation. Additionally radium transfer to vegetation that had transgressed into the ponds has been calculated.

An extensive diagenetic study carried out on a sediment core collected in the Cumbrian mud patch off the Sellafield nuclear reprocessing plant, is presented. Sequential leaching data, using a thoroughly validated protocol specifically designed to prevent any resorption of the released plutonium in the course of the extraction, demonstrate that a significant proportion of the plutonium is loosely bound to sites that readily exchange with seawater, oxidise upon oxygenated water contact (reactive sulphides) or easily dissolve upon changes in pH. Such a result contradicts many previous sequential extraction studies which have reported that little of the plutonium in Irish Sea sediments is in a readily available form. The profile of dissolved plutonium in pore waters indicates an active uptake process at depth, probably linked to sulphide (Acid Volatile Sulphide) precipitation. These reactive sulphides are liable to act as source of plutonium to the overlying water if they are brought close the interface by bioturbation or in contact with oxygenated seawater by burrowing activity.

Les champs de rayonnement à bord des avions subsoniques ont été étudiés au cours des vols Prague – Abu Dhabi – Bangkok et Bangkok – Abu Dhabi – Prague, au mois de février 1995. Un ensemble complexe d'instruments de mesures a été utilisé : un compteur proportionnel équivalent au tissu, un remmètre de neutrons, un débitmètre pour l'environnement ; des détecteurs thermoluminescents, un détecteur solides de traces, et des détecteurs à bulles. Les résultats obtenus sont présentés et analysés ; ils sont confrontés aux résultatsobtenus pendant une période proche au cours de vols Prague – Montréal – Prague. Les conclusions concernent l'influence des paramètres géographiques sur le niveau d'irradiation du personnel navigant.

Les longues séries temporelles d'observation de la radioactivité dans l'atmosphère (au niveau du sol) permettent d'étudier l'évolution de ce réservoir après les injections des expérimentations nucléaires militaires, de l'activité industrielle, ou suite aux accidents tel que celui de Tchernobyl (1986). Conjointement à l'observation des radionucléides d'origine artificielle, les radionucléides formés par l'interaction du rayonnement cosmique dans la haute atmosphère, comme 7Be, sont quantifiés. La corrélation entre les composantes naturelles et artificielles permet de mieux comprendre l'évolution globale de la radioactivité dans l'atmosphère. L'observatoire de la radioactivité dans l'atmosphère de l'Institut de radioprotection et de sûreté nucléaire (IRSN) a débuté en 1959. Actuellement les aérosols sont prélevés dans 6 stations localisées en Métropole et dans 2 stations en Outre-mer (hémisphère sud). Les concentrations de 137Cs dans les aérosols en 2002 sont de l'ordre de 0,4 μBq m-3 en métropole et 10 fois moins à Tahiti. Les activités du 7Be, de l'ordre de 3 200 μBq m-3, sont similaires en métropole et à Tahiti.

The accidental release of large quantities of radionuclide after a nuclear accident tends to contaminate the groundwater system or rivers and lakes by the transfer of the main radionuclides suchas Cesium 137, Strontium 90 or Cobalt 60, Ruthenium 106 and others (including transuranic radionuclides, such as: 239-Pu, 240-Pu, 241-Am...). The aim of this paper is to review the possiblesolutions for the removal of these contaminants from large quantities of water. i) The use of crown ethers for the selective removal of Strontium 90 such as the dicyclohexyl 18-crown 6 which isable to remove with 90% of efficiency the Strontium. ii) The use of zeolithes for the removal of Cesium 137. On larger scale the use of electromagnetic filtration technology is able to process in arelatively short time large quantities of water by using a seeding system of resin coated metallic magnetic particles to enhance the filtering efficiency under cold conditions. Examples of water ofefficiencies and results obtained on loops at a fairly large scale will be given in this paper, these examples show rather high efficiency of removal even at low concentration of contaminants (a fewppb: part per billion). Examples of water treatment concepts will be also given for treatment of contaminated surface water and to treat large groundwater applications. Major applications could beimplemented on various sites namely in Russia (Karatchai Lake) or in Belarus and Ukraine. The magnetic filtration is not a new concept but with the use of various selective adsorbing treatmentparticles, this concept has been proven so effective that dissolved metals in process water have been reduced to level in the very low ppb range.

Airborne 137Cs level in France is not decreasing significantly anymore (mean yearly value around 0,25 µ Bq.m-3 contrarily to what was noticed in the past decades. This observation points out the role of processes that delay the atmospheric cleaning and participate to the persistence of radionuclide in the air at ground-level after a deposit, in the frame of medium as well as long-dated post-accidental contexts. The current background level also yields to consider 137Cs in the atmosphere as a tracer of atmospheric processes like resuspension and re-emission from biomass burnings. This allows us to explain 2/3 of the peaks observed over the last six years. The remaining 1/3 is mainly noticed in winter when spreading of pollutants in the atmosphere is often weak due to temperature gradient inversion. On average, continental air masses are responsible for increases by a factor of 3 while oceanic air masses are characterised by levels 3 times lower, compared to the mean value. Feeding of 137Cs in air at ground-level is the result of both local resuspension that signs 137Cs activity levels in soils to which is added a remote contribution from time to time (resuspension of Saharan dust or re-emission from fires occurring in eastern territories with high 137Cs deposition level). Finally, 137Cs activity levels in air masses crossing over France can be described on average by a longitudinal gradient.

La mesure du tritium sous ses différentes formes (gaz (HT), eau (HTO), ou solide(hydrures)), est une étape importante pour l’évaluation des risques sanitaires etenvironnementaux associés et in fine son estimation dosimétrique. Dansles échantillons du règne végétal ou animal, le tritium est associé à la fraction eaulibre et est inclus dans les composés organiques sous forme de tritium organiquement lié(TOL). Dans ce cas, 2 formes existent : (i) la fraction dite échangeable ou labile (TOL-E)liée à des atomes d’oxygène et d’azote ; (ii) la fraction dite non échangeable (TOL-NE)liée aux atomes de carbones. La technique de référence pour l’analyse du tritium est lascintillation liquide permettant de mesurer des concentrations de l’ordre de quelquesBq.L-1. Les normes (AFNOR, ISO) publiées à ce jour ne concernent quel’analyse du tritium dans l’eau. Seule une méthode CETAMA aborde la mesure du TOL dans desmilieux biologiques. Cette méthode a été testée depuis 2001 via descircuits d’intercomparaisons sur des échantillons d’herbe prélevés dans l’environnement.Concernant l’analyse du tritium dans les eaux, les principaux points forts sont lafiabilité de cette analyse pour des concentrations de l’ordre de 1 Bq.L-1, larobustesse et la simplicité de mise en œuvre. Les points faibles sont essentiellement liésà des problèmes de bruit de fond, de conservation et de contamination des échantillons.Concernant l’analyse du TOL, l’analyse est fiable pour des valeurs de l’ordre de 50Bq.kg-1 d’échantillon frais. Les points faibles sont des problèmes decontamination, de reproductibilité, de temps d’analyse (2 à 6 jours) et l’absence dematériaux de référence. La difficulté à ce jour est la séparation entre TOL-E et TOL-NEqui doit être validée expérimentalement.

During and after the Fukushima accident, the IRSN collected and interpreted the resultsof radiological measurements performed on foodstuffs of terrestrial origin published byJapan's Ministry of Health between mid-March 2011 and July 2012. Analysis of the findingsshows that the accident's date, livestock-rearing practices and the deposits'characteristics had a decisive influence. The fact that radioactive fallout occurred veryearly in the growing and breeding season largely explains the moderate contamination ofmost foodstuffs of terrestrial origin, notably in the areas with the largest deposits. Inthe case of dairy products and meat, feeding imported fodder to livestock in stables, acommon practice in Japan, compounded the calendar effect. Measurements published in Japanhave also borne out the particular sensitivity of mushrooms, including cultivated species,and game.

In this paper, the effect of additional adipose and muscle layers was investigated on theeffective dose and the organ absorbed dose. Calculations were performed using the MonteCarlo N-Particle Transport Code (MCNP) and the ORNL mathematical phantom for externalphoton and neutron beams. Variations in adipose and muscle tissue thickness were modeledby adding layers of adipose and soft tissues around the torso of the phantom. Theeffective dose decreased by about 7%–40% when the thickness of the extra layer increasedfrom 0.5 to 5 cm considering all photon energies (10 keV–10 MeV) and neutron energies(10–9–20 MeV) for anterior-posterior, posterior-anterior, left-lateral,right-lateral, rotation and isotropic irradiation geometries. The results calculated herewere compared with those reported in previous studies such as those of the VIPMAN,NORMAN05, MASH-3 and ICRP reference voxel phantoms. Our data shows that adding properadipose or muscle layers to two very different phantoms can cause similar effective dosevalues, and also more than half of the organ absorbed doses have satisfactoryagreement.

Among the naturally occurring isotopes the determination of radium is the most difficult ones. In this work some alpha-spectrometric source preparation methods to determine radium were measured. The aim of our work was to investigate the feasibility of MnO2-coated discs for radium detection with a semi-conductor PIPS detector. This method based on the sorption of radium onto MnO2-coated surfaces. Parameters of this method were measured, and efforts were made to solve the incidental problems. In the case of using polyamide discs for base material, the executed experiments were showed that it might be applied to detection of 226Ra, however the resolution was weak. It can be caused by the surface roughness and by the width of the MnO2 coat. In the consecutive investigates we have these parameters changed. Whereas the surface roughness of MnO2 cannot be changed more, smooth surfaces could produce in another way, so there were took several surfaces into account, like stainless-steel, nickel, copper and chrome plate. Regarding our results - in the case of optimal width of MnO2 coat - using MnO2-coated discs is a simple and effective source preparation method in radium measurement.

There is currently a revitalized concern about the potential impact of ionizing radiation on the environment that calls for the construction of a system ensuring an adequate radioprotection of the non-human biota and their associated biotopes. This paper first sets the context of the problem both, with respect to the general philosophy of environmental protection as a whole, but also with respect to the consideration of the environment achieved so far in the purpose of human radioprotection. The current accumulated knowledge on the effects of ionizing radiation to biota (fauna and flora) is then briefly reviewed, encompassing effects at individual and community/ecosystem level, situations of acute and chronic exposure to high and low doses, finally leading to the identification of the most critical gaps in scientific knowledge: effects of mixed low dose rates in chronic exposure to communities and ecosystems. The most significant current international efforts towards the identification of environmental radioprotection criteria and standards are finally presented along with some relevant national examples.

Experience following the Chernobyl accident in the CIS and the EU has clearlydemonstrated that policies and strategies for long-term management of extensivecontaminated areas must give due importance to social, cultural, ethical, environmental,economic and political factors beyond the sole radiological protection and healthperspective. What is at stake in the long-term response to such a situation is thesustainable rehabilitation of living conditions in affected territories, in a context inwhich each person can actively contribute to his own protection. Preparing or developingrehabilitation of living conditions in a territory affected by long-lasting radioactivecontamination is a broader issue of governance as it must address all affected dimensionsand articulate the actions of the various concerned actors at the local, regional andnational level. To respond to this challenge, a specific research project was implementedby Mutadis, CEPN, NRPA and AgroParisTech from April 2004 to June 2009 in the framework ofthe EURANOS integrated programme. The overall objective of this project was “todevelop a strategic and methodological framework that can inform or assist nationalauthorities in Europe in establishing arrangements for the long-term management and thesustainable rehabilitation of living conditions in extensive areas that may becontaminated as a result of an accident or malevolent act involving radioactivematerial”. The proposed framework describes a two-steps method allowingnational and local authorities together with key stakeholders to establish arrangementsand preparation strategies in the perspective of long-term management of a radiologicalevent. It may also be used to develop rehabilitation strategies in countries affected bylong-lasting radioactive contamination. This framework aims to set up favourableconditions for stakeholders (in particular local communities) to engage effectively andsustainably in the cooperative development of post-accident preparation or managementstrategies. The first step of the method aims to frame the issue and identify conditionsfor stakeholders to engage in rehabilitation preparedness or management strategies. Thesecond step aims to develop a local-national cooperation platform gathering local andnational, private and public actors to develop together preparation or managementstrategies.

Ebro River extends over almost 930 km and is the main Spanish river entering theMediterranean Sea. There are several industries located along this river course includinga dicalcium phosphate factory (DCP) and two nuclear power reactors. These installations,together with other factors such as the geology, can contribute to the radiologicalcontent of the river. Therefore, this study was performed to determine some natural andalso some anthropogenic radionuclide concentrations in the Ebro River ecosystem. Weanalysed water samples, solid samples (rice field sludge and surface marine sedimentsamples), and also biota samples (Cladophora glomerata andCynodon dactylon). For water samples, gross alpha, gross beta, tritium,uranium, thorium and also a group of gamma-emitting isotopes’ activities were determined.The main contribution to radioactivity for these samples was due to some isotopes from theuranium and thorium chain. For the solid samples, we quantified some natural andartificial gamma radioisotopes, which may be related to the geological and/or industrialactivities located in this zone. In the case of biota, the results indicate that thepresence of the DCP has a significant influence, since the highest activity was observedin the surroundings of this industry (Flix), where isotopes such as 214Bi and214Pb presented activity values of 105  ±  43 Bq/kg and 100  ±  58 Bq/kg,respectively.