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Nuclear power and modern agriculture are two crucial sectors for sustainable development in the United Arab Emirates (UAE). As these industries mature rapidly in the country, their long-term inter-compatibility needs monitoring with local data on transfer of radionuclides from arid sandy soils to farm products. Date palms, main crop from the Arabian Peninsula, remain largely unstudied for radioecological impact assessments. This paper reports the first measurement of soil to UAE date palms concentration ratios for natural radionuclides. Representative samples of soils, fruits, and leaves from seven palms in Abu Dhabi have been studied using gamma-spectrometry. Average activity concentrations in the soils are around 278.9 Bq kg−1 for 40K, 15.5 Bq kg−1 for 238U, and 8.3 Bq kg−1 for 232Th. The latter two decay chains, in the plant samples, are close to detection limits, signifying their lower levels in the UAE flora and the need for upgrading analytical techniques. The geometric means of soil to fruit concentration ratios are 1.12 for 40K, but negligibly low for the others—approximately 0.08 for 238U and 0.17 for 232Th chains. The respective ratios for the leaves are approximately 0.13, 0.36, and 0.77. Personal radiation doses due to soils and dates are very low, posing no danger to the public.

Gender balance refers to the equitable treatment and access to opportunities for all genders. In order to achieve true gender balance, a variety of proactive approaches developed collaboratively, with insight from multiple perspectives, need to be implemented. With that purpose, the participation of women in professions related to radiation and radiation protection was prioritised and given high visibility by allocating a ‘Women in Radiation’ (WiR) Special Session at the 15th International Congress of the International Radiation Protection Association (IRPA), hosted by South Korea on 20 January 2021. In this session, various issues related to gender balance and equity/equality were highlighted by the panellists, and further elaborated in a subsequent discussion with attendees. The main goal of the WiR Special Session was to convene women from different organisations, career and age stages, disciplines and countries, in particular to consider the Asian–Oceanic vision and status of gender equality, along with other topics to support a ‘Call for Action’, with concrete recommendations subsequently provided to IRPA. The discussion stressed the main needs and challenges faced by women working in various radiation fields, along with raising awareness of possible professional and employment opportunities. This paper identifies some steps necessary to encourage, enhance and support the inclusion of more diversity in nuclear professions with specific emphasis on women. In conclusion, gender balance and equality must be at the heart of any strategic plan for the future of the radiological protection profession; international cooperation between relevant bodies is essential for success and could serve as a catalyst for specific policy statements aimed at achieving a balanced representation of women in radiological protection.

Since the last decade, ambitious nuclear power programmes have begun maturing in the Arab countries, most importantly in the United Arab Emirates (UAE). The region's environment and population, therefore, are prone to adverse, long-term impacts of radionuclide discharges. To calculate the associated exposure scenarios, to estimate doses and their consequences, and finally, to lay out a radiological emergency management plan, arid region radioecology is taking shape in the UAE as a major field of research. Geography, demography, food habits, weather, soil, water, flora, and fauna of the desert-marine regions are quite distinct from their temperate counterparts. This results in the need to increase the knowhows of environmental migration and bioaccumulation of radionuclides in the region's agricultural ecosystems. In this paper, we present a detailed review of the measured data from the UAE and nearby nations, generating insights for the soil radioactivity and soil-to-plant transfer phenomena under local arid conditions. In the literature, the radionuclide activity concentrations (in Bq kg

The root uptake of radiocaesium by different plant parts of Swiss chard (Beta vulgaris L. var. cicla), cabbage (Brassica oleracea L. var. capitata) and sweet corn (Zea mays L. var. saccharata ) and the potential influence of K-fertilising on the transfer behaviour was studied in allophanic volcanic soils (umbric andosol and dystric fluvisol) in Chile under temperate climate and heavy rainfall conditions (∼2660 mm y −1 ) over several vegetation periods. The soils were spiked homogeneously to 0.20 m depth with 100 kBq 134 Cs m −2 and activity concentrations measured. The transfer factor (TF, on a dry mass basis) to Swiss chard had a clear exponential decrease within each crop year for both soil types, either K-fertilised or unfertilised. The highest values of the TFs to Swiss chard were at the beginning of the harvests, and the half-times of TF decrease ranged between 52 and 137 d for umbric andosol and between 40 and 164 d for dystric fluvisol. Over the five seasons there was no consistent ageing effect based on TF in either soil types for the three studied crops. The effect of 134 Cs foliar uptake by Swiss chard from resuspended soil was estimated to account for about 70% (external leaves) and 30% (internal leaves) increase in the TF for the K-unfertilised umbric andosol, and showed an ambiguous behaviour for the K-fertilised umbric andosol. Consequently foliar uptake does not explain the 370 and 500% increase of the TF to Swiss chard leaves determined during the third growing period in the umbric andosol without and with K-fertilisation, respectively. Therefore an uncertainty factor of 3–5 is recommended to be taken into account when using this parameter for dose calculations. The TF to Swiss chard was found to be higher than previously reported values. The TF to cabbage and sweet corn plant parts was found to be within the range of previously reported values. Normal K-fertilisation resulted in about 2.4-fold reduction in 134 Cs TF to Swiss chard, 2.3-fold to sweet corn and 3.0-fold to cabbage.

Over 150 publications reporting studies conducted in the former USSR were reviewed to provide transfer coefficients (F(f)) to the muscle of domestic animals from experiments using chronic administration, often for long timescales in large scale experiments. Only a few of these studies were made available in the English language literature or taken into account in international reviews. The values derived have been compared with expected values reported by the IAEA's Handbook of parameter values for the prediction of radionuclide transfer in temperate environments (TRS 364) where possible. The information presented here has been used in the current updating of parameters recommended for environmental assessments by the IAEA. Many of the reported values are for Sr due to the Mayak accident and Cs due to the Chernobyl accident. Nevertheless, the reported data for a wide range of radionuclides, in particular for Ru, Sb, and Zn markedly improve the extent of available data.

April 2016 sees the 30th anniversary of the accident at the Chernobyl nuclear power plant. As a consequence of the accident populations were relocated in Belarus, Russia and Ukraine and remedial measures were put in place to reduce the entry of contaminants (primarily 134+137Cs) into the human food chain in a number of countries throughout Europe. Remedial measures are still today in place in a number of countries, and areas of the former Soviet Union remain abandoned. The Chernobyl accident led to a large resurgence in radioecological studies both to aid remediation and to be able to make future predictions on the post-accident situation, but, also in recognition that more knowledge was required to cope with future accidents. In this paper we discuss, what in the authors' opinions, were the advances made in radioecology as a consequence of the Chernobyl accident. The areas we identified as being significantly advanced following Chernobyl were: the importance of semi-natural ecosystems in human dose formation; the characterisation and environmental behaviour of ‘hot particles'; the development and application of countermeasures; the “fixation” and long term bioavailability of radiocaesium and; the effects of radiation on plants and animals.

Radiological assessment of the impact of nuclear weapons testing on the local population in the Semipalatinsk Test Site (STS) requires comprehensive site-specific information on radionuclide behaviour in the environment. However, information on radionuclide behaviour in the conditions of the STS is rather sparse and, in particular, there are no data in the literature on parameters of radionuclide transfer from feed to rabbit products which have been identified as contributors to internal dose to the inhabitants. The transfer of (137)Cs and (90)Sr to rabbit meat was studied under laboratory conditions in a controlled experiment with 32 locally bred rabbits maintained in the Kazakh Agricultural Research Institute. The equilibrium transfer coefficients for (137)Cs and (90)Sr from feed to rabbit meat were estimated to be 0.4 d kg(-1) and 0.15 d kg(-1), respectively. The biological half-lives were estimated to be 0.1 d for (137)Cs and 0.14 d for (90)Sr. Whereas for (137)Cs the distribution in the body is relatively homogeneous, there are large differences between the organs and tissues for (90)Sr for which, as expected, the highest concentrations were found in bone.

A wide range of different countermeasures has been used to mitigate the consequences of the Chernobyl accident for agriculture in affected regions in Belarus, Russia and Ukraine. The paper comprehensively brings together key data on countermeasure application over twenty years for all three countries and critically evaluates the response to the accident with respect to agriculture. The extents of countermeasures implementation in various periods following the ChNPP accident are documented. Examples of best practices and drawbacks in remediation of affected areas are identified. Data on the effectiveness of agricultural countermeasures have been evaluated and the impact of countermeasures implementation to mitigate consequences of the accident has been assessed for the period 1986-2006. Implementation of agricultural countermeasures averted 30-40% of the internal collective dose that would have been received by the residents of affected regions without the use of countermeasures. The current situation in agriculture of areas subjected to contamination following the Chernobyl accident is described. Current and future needs for remediation, including a consideration of various strategies of rehabilitation of affected areas are presented.

After an accidental release of radionuclides to the inhabited environment the external gamma irradiation from deposited radioactivity contributes significantly to the radiation exposure of the population for extended periods. For evaluating this exposure pathway, three main model requirements are needed: (i) to calculate the air kerma value per photon emitted per unit source area, based on Monte Carlo (MC) simulations; (ii) to describe the distribution and dynamics of radionuclides on the diverse urban surfaces; and (iii) to combine all these elements in a relevant urban model to calculate the resulting doses according to the actual scenario. This paper provides an overview about the different approaches to calculate photon transport in urban areas and about several dose calculation codes published. Two types of Monte Carlo simulations are presented using the global and the local approaches of photon transport. Moreover, two different philosophies of the dose calculation, the “location factor method” and a combination of relative contamination of surfaces with air kerma values are described. The main features of six codes (ECOSYS, EDEM2M, EXPURT, PARATI, TEMAS, URGENT) are highlighted together with a short model–model features intercomparison.

In many regions subjected to the contamination after the ChNPP accident forest products play an important role in radiation impact on the population. The decision making framework to optimise implementation of forest countermeasures in the long term after the ChNPP accident is described. The approach is based on the analysis of the main exposure pathways related to contaminated forest and application of different criteria (reduction of individual dose, cost for implementation; cost of averted dose of 1 man-Sv; secondary ecological effect and psycho-social impact) for the selection of optimal countermeasures strategies. Results of the application of the approach proposed for the study area (Novozybkov district, Russian Federation) are presented. The results emphasize the effectiveness of the application of a flexible decision support technologies for the optimization of countermeasures taking into account radioecological and economic features of contaminated forests.

The Semipalatinsk nuclear test site (STS) in the Republic of Kazakhstan was an important site for testing atomic bombs and other civil and military nuclear devices of the former Soviet Union. Results are presented from investigations on the extent of radiostrontium contamination in soils and vegetation at the technical areas of the STS, where the tests were conducted and in pastures used by farmers for grazing animals or for hay production. Our data are compared with those reported largely in the recent Russian language literature that has been reviewed. The extent of (90)Sr contamination of soil is highly variable over the STS with the highest values associated with the technical areas, particularly the Degelen mountains. Recently measured values in both the present data and the Russian language literature confirm the relatively high current contamination of soil and vegetation in the vicinity of tunnels and associated watercourses in the Degelen area. The proportion of (90)Sr in soil which could not be extracted with 6 M HCl was only an average of 20%, which is low compared to other test site areas and possibly indicates a relatively high mobility in this area, because the (90)Sr is derived from leakage from explosion tunnels along watercourses rather than being associated with fused silicates. A comparison of relative activity concentrations in soil and vegetation suggests that the transfer of (90)Sr to vegetation on the STS is high compared to that of (137)Cs and plutonium.

The STRATEGY project (sustainable restoration and long-term management of contaminated rural, urban and industrial ecosystems; www.strategy-ec.org.uk) addressed the need for a holistic decision framework for the selection of optimal remediation strategies for long-term sustainable management of contaminated areas in Western Europe. The project considered both technical and social aspects of implementing restoration strategies for urban and rural environments. The importance of considering socially relevant objectives in addition to the dose reduction was emphasised. A critical evaluation was carried out on 101 selected countermeasures, (including rural waste disposal options), a model was developed to aid optimising countermeasure strategies and a method of carrying out participatory decision-making suggested. The outputs of the project are described and critically evaluated.

In this work, soil-to-plant transfer factors of radiocaesium are predicted based on soil properties such as pH, organic matter content, exchangeable K+ and clay content valid for the tropical environments in Bangladesh, China and Japan, and using a previously published model. Due to insufficient data of soil properties in the selected regions, the average values of pH, organic matter content, exchangeable K+ and clay content were taken as the input model parameters within the ranges given for Asia. Nevertheless, a complete set of soil properties of Japanese soils was used to compare the measured and calculated TF values of radiocaesium for radish. The calculated TF values for radiocaesium are comparable with the measured values especially for leafy parts of a plant. However, calculated values for rice, an important crop in Asia are found to overestimate the measured values due to an overestimate of calculated CECs in soils in the selected regions. The empirical parameters used in the model need to be re-evaluated for the specific part of a plant and/or for a variety of different plants. Alternatively, a general conversion factor for each part of a plant and/or for a variety of different plants for a specific region is suggested for tropical environments.

The spatial distribution and vertical migration of global fallout (137)Cs were studied in soils from South Patagonia at the austral region of South America in semi-natural and natural environments located between 50-54 degrees S and 68-74 degrees W. The (137)Cs areal activity density varied from 222 to 858 Bq m(-2), and was found to be significantly positively correlated (p

After the release of radionuclides into the environment it is important to be able to readily identify major routes of radiation exposure, the most highly exposed individuals or populations and the geographical areas of most concern. There have been significant recent improvements in our capability to estimate spatial variation in the environmental behaviour of radionuclides through better understanding of the underlying processes and an ability to spatially apply this knowledge by integrating relevant spatial information in the form of digital data sets using geographical information systems. Thus, it is now possible to refine the estimation of spatial variation in radiation exposure, both for routine releases and in accident situations. Within a recent EC-funded concerted action (the Radioecological Sensitivity Forum), there has been a renewed consideration of the concept of radioecological sensitivity with a particular focus on identifying sensitive areas as well as processes and communities. The concept should be relevant for both terrestrial and aquatic ecosystems, and might even be applied for consideration of doses to biota, although the current focus has been restricted to a consideration of human exposure. The conclusions of the action are outlined, considering the potential usefulness of the concept, and methods by which it can be applied. A framework for the estimation of radioecological sensitivity is proposed and the various measures by which it can be considered, including (i) aggregated transfer coefficients, (ii) action loads, (iii) fluxes and (iv) individual exposure of humans are discussed. The importance of spatial and temporal consideration of each of these outputs is emphasized.

In Chile unexpectedly high 137 Cs activity concentrations in soils and in food products due to the weapons fallout in the 60* have been detected. This is partly due to the prevailing climatic conditions fliigh precipitation rates) and the soil characteristics of the Chilean soils especially in the 10* administrative Region Within an EC project of the 4 th framework: programme in Nuclear Fission Mastering Event of the Past (RESTORE 'restoration strategies for radioactive contaminated ecosystems') an EDSS (Environmental Decision Support System) has been developed which can be adapted to the ecological and site specific conditions of Chile by using information on soil properties, soil contamination and soil-plant transfer factors of n7 Cs for characteristic Chilean soil types and crops. These data can be used to identify areas which are potentially radioecological sensiUve i.e. will result in elevated radiation doses to people living and using these areas, and further more where countermeasure actions might he implemented. The EDSS will use the modern tools such as GIS (geographical information systems) and geostatisticat methods, recently developed dynamic soil-plant transfer models lo determine fluxes of radiocaesium, and dose calculation models. The system will provide an analysis of the present contamination with radiocaesium of Chile. Later it can be modified and applied for other radionuclides such as radiostrontiu m. Examples for the implementation of the EDSS and first results are presented.

To sustain acceptable living and working conditions in areas contaminated by radioactivity, robust and effective restoration strategies need to consider different types of environment, land use and ways of life. The allocation of resources must take account of a range of requirements to ensure sustainable use, including social and ethical aspects, environmental considerations and quality of life. Current understanding of public perceptions and communication of technical information also needs to be integrated into the process so that the radiological situation is fully explained and any remediation measures are transparent to, and agreed by, affected populations. Many individual countermeasures have been developed and tested. Previously, the focus has been on evaluating their effectiveness, with some attention to cost. The current STRATEGY project aims to establish a more holistic decision framework for the selection of optimal remediation strategies for long-term sustainable management of contaminated areas. An initial step within this approach is a detailed evaluation of individual countermeasures; examples of which are provided here for an agricultural and urban countermeasure.

A method is presented to determine the kerma rate in air from 137 Cs due to Chernobyl fallout in forests. In situ gamma-ray spectra from several forest sites in Russia, in the Ukraine and in Southern Germany are evaluated with the aim of deducing the ratio of primary and forward scattered photons for 137 Cs. With this ratio and the results of Monte-Carlo simulations of photon transport the contribution of scattered photons to the total kerma is assessed successfully. Scattered photons contribute between 42% and 50% to the total kerma rate from radiocesium, which is less than according values for grassland areas. The contribution of radiocesium to the total kerma rate varies between 40% and 90%, whereas radiocesium stored in the forest biomass contributes only a few percent. The mean mass depth of radiocesium ranges from 2.6 to 6.4 g cm −2 in the forest soils.

A recently developed semi-mechanistic temporal model is used to predict food product radiocaesium activity concentrations using soil characteristics available from spatial soil databases (exchangeable K, pH, percentage clay and percentage organic matter content). A raster database of soil characteristics, radiocaesium deposition, and crop production data has been developed for England and Wales and used to predict the spatial and temporal pattern of food product radiocaesium activity concentrations (Bq/kg). By combining these predictions with spatial data for agricultural production, an area's output of radiocaesium can also be estimated, we term this flux (Bq/year per unit area). Model predictions have been compared to observed data for radiocaesium contamination of cow milk in regions of England and Wales which received relatively high levels of fallout from the 1986 Chernobyl accident (Gwynedd and Cumbria). The model accounts for 56% and 80% of the observed variation in cow milk activity concentration for Gwynedd and Cumbria, respectively. Illustrative spatial results are presented and suggest that in terms of food product contamination areas in the North and West of England and Wales are those most vulnerable to radiocaesium deposition. When vulnerability is assessed using flux the spatial pattern is more complex and depends upon food product.

Over the last decade, there has been considerable progress in the development of countermeasures for preventing or reducing contamination of animal products by radioisotopes of iodine, caesium and strontium. In this paper, recent significant technical improvements are summarised and the current availability of countermeasures and their usefulness in the event of a nuclear accident reviewed. An improved understanding of factors controlling the metabolism of radioiodine and radiostrontium has enabled previously suggested countermeasures to be either optimised or dismissed. For radiocaesium in particular, experience since the Chernobyl accident has enabled effective and feasible countermeasures to be identified and successfully implemented in different situations. It has also been more widely understood that countermeasure effectiveness, although important, is not the only criterion which needs to be determined. In addition, cost and practical considerations such as availability, technical feasibility, acceptability and side-effects need to be taken into account. Evaluation of these factors has shown that some previously recommended countermeasures are unlikely to be feasible.

The influence of the stable iodine content in the diet on the absorption of radioiodine and its transfer to cow's milk was investigated for cows at different stages of lactation. Three different rates of stable iodine: a low intake rate of 4 mg d −1 , a moderate intake of 35 mg d −1 and a high rate of 75 mg d −1 were fed to two groups of three lactating cows in mid- and late-lactation. The transfer to milk of a single oral administration of radioiodine was measured for the three different intake rates. The lactation phase had no significant effect on iodine transfer to milk; therefore, the data from the two lactation groups were pooled for further statistical analyses. The mean transfer coefficient values for oral radioiodine to milk increased from 0.020 d l −1 for the low treatment to 0.024 d l −1 for the moderate stable iodine rate. There was a statistically significant decrease in the transfer to milk for the high stable dietary iodine intake rate (mean transfer coefficient=0.018 d l −1 ) compared with the moderate treatment. These differences were not due to effects on absorption since true absorption was complete for all three stable iodine treatments, but rather to differential affinities and saturation levels of the thyroid and milk pathways competing for the available iodine. The same behaviour and comparable values of transfer coefficients (range 0.015–0.020 d l −1 ) were observed for stable iodine.

Ingestion of milk contaminated by radioiodine (most especially 131 I) represents an important potential route of radiation exposure to humans in the event of a nuclear accident. Oral administration of stable iodine to dairy ruminants has previously been suggested as an effective countermeasure to reduce radioiodine levels in milk. However, previous data on its effectiveness are contradictory, and little attention has been given to the most appropriate time to administer stable iodine relative to the time that an animal is first exposed to radioiodine. The effectiveness of 1g KI orally administered to lactating goats 12 h before and 12 h after contamination with pulse doses of radioiodine was investigated. Administration of KI prior to the ingestion of radioiodine was shown to reduce the transfer to milk by 50% compared to a reduction of approximately 40% when KI was administered 12 h after radioiodine. The administration of KI 12 h prior to radioiodine contamination effectively reduced the transfer of radioiodine to the thyroid by approximately 90%. When administered 12 h after radioiodine, the KI stopped subsequent uptake of radioiodine by the thyroid. The maximum level of iodine in milk, as a consequence of the administration of KI, was 20 mg I kg −1 . This was 40-fold higher than the maximum permissible level of iodine in milk of 0.5 mg l −1 currently set in some countries. Further consideration is required on stable iodine administration regimes for different scenarios and the consequent increase in the stable iodine content of the milk of different dairy animals.

Following a large-scale release of radioactivity into the environment, food production systems and inhabited areas may be contaminated for many years. Accident response throughout Europe has tended to focus on management of the early phase, addressing issues such as evacuation, sheltering, restrictions on food and drinking water and provision of stable iodine tablets. Currently there is little systematic consideration of the long-term management to ensure the sustainability of contaminated areas. To sustain acceptable living and working conditions in such areas it is necessary to construct practicable restoration strategies that take into account the views of a wide range of stakeholders. Under the auspices of the European Commission’s 5th Framework Programme, funding was provided for two complementary projects (FARMING1 and STRATEGY2) to develop strategies for maintaining agricultural production and safe food supplies in the long term through stakeholder consultation. The FARMING project, which started in November 2000, established a network of stakeholder groups in the UK, Finland, Belgium, France and Greece, involving more than 100 individual stakeholders. The five national groups belonging to the FARMING network have met regularly since 2000 to discuss and evaluate countermeasure strategies. Much of the information on countermeasures for food

The transfer of 137 Cs, 85 Sr, 131 I, 210 Po, 210 Pb and 238 U from feed to camel's milk was investigated in a pilot experiment with three lactating camels. For a period of 60 days, the animals were fed on spiked feed containing the studied radionuclides. They were subsequently returned to a contamination-free diet and monitored for another 90 days. The activity concentrations of 137 Cs, 85 Sr and 131 I in milk decreased with time and reached background levels after 20 days. Equilibrium transfer coefficients and biological half-lives were estimated and transfer coefficients were calculated as (8.1 ± 3.6) × 10 −4 , (4.4 ± 1.6) × 10 −2 , (7.8 ± 3.9) × 10 −4 , (2.7 ± 3.5) × 10 −4 , (1.8 ± 1.5) × 10 −4 and (7.0 ± 3.6) × 10 −3 d L −1 for 85 Sr, 131 I, 137 Cs, 210 Po, 210 Pb and 238 U, respectively. The biological half-lives were estimated to be 6.4, 4.2, 8.9, and 53.3 days for 85 Sr, 131 I, 137 Cs, and 238 U, respectively. Estimates of the half-lives were based on a one component model: it was found that the half-life values measured for artificial radionuclides were slightly shorter than those for natural radionuclides. The data obtained in the study are the first published experimental data on radionuclide transfer to camel milk.

Several radioecological experiences with isotopes of ruthenium, iodine, caesium and barium, obtained after the reactor accident of Chernobyl, are reported. It was found that for a wet deposition barium was the element with the highest retention on grass. The retention of caesium was lower by a factor of 1.6, retention of iodine by a factor of 2.4 and retention of ruthenium by a factor of 3.5. Former data on the caesium transport in cereals from leaves to grain were confirmed. Depending on the conditions the iodine transfer factor for milk varied between 0.002 and 0.007 d.kg-1. The caesium transfer factor for milk was (0.003 +/- 0.0006) d.kg-1 and was found to be relatively constant in the years 1986-1988. In 1991, the values were higher by a factor of 2-5. Radioecological model results of whole-body burdens in Southern Bavaria showed a reduction of the caesium ingestion doses due to countermeasures and spontaneous changes of consumption habits in the first 2 months by a factor of 5 and till the end of 1987 by a factor of 1.5. The model results agree well with the range of measured whole-body burdens. One month after the deposition, the external exposures in urban environments due to ruthenium, caesium and barium isotopes were found to be reduced by a factor of 2, compared with open lawns, in the case of iodine the reduction was even a factor of 2.5. External exposures of a population group from the Munich area were determined by thermoluminescence dosimetry. The results are in accordance with the spectral measurements of external dose rates in urban environments.

After major nuclear accidents the most effective action to reduce activity levels in animal products is to provide uncontaminated feed or feed diluted with uncontaminated material. However, uncontaminated feed may not always be available in such situations. Therefore other effective procedures are needed to reduce activity levels which must be easy to apply, low in cost and have no side effects on animals and their products. Chemical substances administered as feed additive to housed or grazing animals act by influencing gut absorption or increasing the rate of excretion from blood and organs. The main chemical methods used are: (1) dilution of radionuclides by stable isotopes or analogous inactive elements; and (2) natural or artificial binding agents. In this paper a summary and critical review of the different chemical methods described in the literature is given.

The distribution and the biological half-lives of 137Cs in poultry after continuous intake of foodstuffs contaminated by the Chernobyl fallout were studied in order to determine transfer coefficients to yolk, albumen, and shell of eggs as well as transfer coefficients to chicken meat. Mean values for laying hens were found to be 0.2 d kg-1 (whole consumable egg), 1.2 d kg-1 (leg meat), and 1.6 d kg-1 (breast meat) when radiocesium was fed in contaminated grass pellets, and about twice as large [i.e., 0.4 d kg-1 (whole consumable egg), 2.8 d kg-1 (leg meat), and 3.0 d kg-1 (breast meat)] when radiocesium was fed in contaminated wheat. Reducing effects of the feed additive ammonium-ferric-cyano-ferrate in concentrations of 0.66 g kg-1 of feed mixture on the contamination of hen products were quantified to be a factor of 3 to 4 (whole consumable egg and meat after grass pellet feeding) and 8 to 14 (whole consumable egg and meat after wheat feeding). A drastically higher reduction with an ammonium-ferric-cyano-ferrate dose twice as large (1.33 g kg-1) was achieved. For broiler chickens, activity concentration ratios of meat to feed were derived for various fattening periods, with mean values of about 0.3 (leg), 0.4 (breast), and 0.2 (liver). The addition of ammonium-ferric-cyano-ferrate reduced the activity concentrations in meat by factors of more than 6.

Publisher Summary This chapter reviews the main environmental, social, and ethical issues associated with remediation. The environmental secondary effects and social and ethical aspects of remediation are strongly interlinked—for example, economic and environmental effects heavily influence the wellbeing and comfort of an affected population. The chapter provides an overview of environmental side-effects and the consequences of remediation measures carried out after Chernobyl, including an estimate of economic costs, and summarizes the main ethical and social aspects of dose-reduction measures. It addresses some of the remedial actions that are not primarily intended to reduce dose, such as compensation or information schemes. In most cases, remedial measures are applied after considerations of dose reduction to humans in the short, medium, and long terms. In the chapter, the so-called side or secondary effects of remedial actions are discussed.

Publisher Summary This chapter describes the topics of importance for any site evaluation, providing an informed decision for remediation. It demonstrates the need to characterize the different release scenarios and to determine the radio-ecological sensibility/vulnerability of a contaminated site. It also provides very practical advice on planning, field and laboratory measurements, verification of data, and the role of quality analyst (QA) and quality control (QC) within the whole survey and remediation process. This information should help to improve the survey planning, the survey, and the pathway analysis for optimized remediation strategy. Site characterization represents the first necessary stage in the remediation of any contaminated environment. Indeed, all decisions for the evaluation of need for site remediation—further remediation planning and the implementation of remedial actions—and post remediation for the assessments (to ensure that there is compliance of the residual concentrations of radionuclides in the environment with the expected levels) are based on the site characterization.

Publisher Summary This chapter discusses the transfer of radionuclides in animal production systems. It provides an overview of (1) the most important contamination pathways, (2) fluxes and sinks of radionuclides, (3) how transfer can be described and quantified, and (4) some potential countermeasures. During recent years, novel data from animal experiments have become a rarity and, with time, the number of research groups carrying out such research has declined so that few groups in Europe or elsewhere currently conduct such experiments. Most of the data available are related to well-studied radionuclides of Cs, Sr, and I, and many have been obtained as a consequence of the Chernobyl accident. Fewer studies have dealt with radionuclides that are important from other perspectives, such as Tc, S, Cl, U, and 3H for which data are sparse. In addition to the need for data on transfer to animal products, which constitute major human dietary components, there is a need for data regarding unusual animal derived products that can be important for individual consumers whose dietary habits may expose them to radionuclide ingestion to a greater degree than the average population.

An extensive programme of experiments was conducted in the former USSR on transfer of radionuclides to a wide range of different agricultural animals. Only a few of these studies were made available in the English language literature or taken into account in international reviews of gastrointestinal uptake. The paper gives extended information on Russian research on radionuclide absorption in the gut of farm animals performed in controlled field and laboratory experiments from the 1960s to the current time. The data presented in the paper, together with English language values, will be used to provide recommended values of absorption specifically for farm animals within the revision of the IAEA Handbook of Parameter Values IAEA [International Atomic Energy Agency, 1994. Handbook of Parameter Values for the Prediction of Radionuclide Transfer in Temperate Environments, IAEA technical reports series No. 364. International Atomic Energy Agency, Vienna].

The accident at the Chernobyl NPP (nuclear power plant) was the most serious ever to have occurred in the history of nuclear energy. The consumption of contaminated foodstuffs in affected areas was a significant source of irradiation for the population. A wide range of different countermeasures have been used to reduce exposure of people and to mitigate the consequences of the Chernobyl accident for agriculture in affected regions in Belarus, Russia and Ukraine. This paper for the first time summarises key data on countermeasure application over twenty years for all three countries and describes key lessons learnt from this experience.

The transfer of 90Sr to a range of different plant species grown on a range of different soil types in Kazakhstan, including three from the Semipalatinsk Test Site (STS), has been measured in a lysimeter experiment. 90Sr uptake by Stipa spp was significantly higher than for other vegetation species. The uptake of 90Sr from chernozem was significantly lower than that from the other soil types which is consistent with other literature. There was a significant negative relationship between 90Sr uptake and calcium, humus and CEC concentration in the soil for Agropyrum spp, Artemisia spp but not for Stipa spp or Bromus spp. The transfer to vegetation from soil has been quantified using the aggregated transfer coefficients for each species. Tag values range from 0.6 to 11.9 m2 kg − 1× 10− 3 over all measurements. The transfer of 90Sr to plants from the Kazakh soils was low compared to previously reported data and to that given from literature reviews.

For testing the potential use of stable iodine as a countermeasure to reduce radioiodine transfer to milk, concentrations of stable iodine and radioiodine in the milk of dairy cows fed different amounts of stable iodine were measured. The results indicated that, compared to a normal average stable iodine intake of about 20 mgd -1 for cows, low iodine dietary intake (

Summary • Radiocaesium is one of the main anthropogenic sources of internal and external exposure to β- and γ-radiation (e.g. from global fallout of atmospheric atomic bomb testing and from the Chernobyl reactor accident). Here we investigated gene expression by suppression subtractive hybridization (SSH) and reverse transcription–polymerase chain reaction (RT–PCR) in Arabidopsis thaliana, which was induced by the root uptake of 134Cs. • SSH analysis resulted in the isolation of 46 clones that were differentially expressed at 30 Bq cm−3 134Cs. Most of the expressed sequence tags identified belonged to genes encoding proteins that were involved in cell growth, cell division and the development of plants, and in proteins controlling translation, general metabolism and stress defence, including a DNA excision repair protein. • The accumulation of caesium in plant material was measured in plants grown for 5 wk on agar contaminated by up to 60 Bq cm−3 134Cs. 134Cs was found to accumulate, in particular, in leaf rosettes and was dependent on the activity concentration in the growth media. • The data indicate that low-level ionizing radiation influences important cellular responses, resulting in a changed gene-expression profile.

The STRATEGY project (Sustainable Restoration and Long-Term Management of Contaminated Rural, Urban and Industrial Ecosystems) aimed to provide a holistic decision framework for the selection of optimal restoration strategies for the long-term sustainable management of contaminated areas in Western Europe. A critical evaluation was carried out of countermeasures and waste disposal options, from which compendia of state-of-the-art restoration methods were compiled. A decision support system capable of optimising spatially varying restoration strategies, that considered the level of averted dose, costs (including those of waste disposal) and environmental side effects was developed. Appropriate methods of estimating indirect costs associated with side effects and of communicating with stakeholders were identified. The importance of stakeholder consultation at a local level and of ensuring that any response is site and scenario specific were emphasised. A value matrix approach was suggested as a method of addressing social and ethical issues within the decision-making process, and was designed to be compatible with both the countermeasure compendia and the decision support system. The applicability and usefulness of STRATEGY outputs for food production systems in the medium to long term is assessed.

The radiological assessment of the impact of nuclear weapon's testing on the Semipalatinsk Test Site (STS) on the local population requires comprehensive site-specific information on radionuclide behaviour in the environment. However, information on radionuclide behaviour in the conditions of the STS is rather sparse and, in particular, there are no data in the literature on parameters of radionuclide transfer from feed to horse products proofed to be important contributors to the internal dose to the local population. The transfer of 137 Cs and 90 Sr to horse milk and meat was studied under laboratory and field conditions: in controlled experiment with three lactating horses maintained in the Kazakh Agricultural Research Institute, and in field measurements of horse products taken from horses grazing at the Semipalatinsk Test Site. The equilibrium transfer factors from feed to horse milk and meat were estimated to be 0.012 d l −1 and 0.035 d kg −1 for 137 Cs and 0.0022 d l −1 and 0.003 d kg −1 for 90 Sr, respectively. The biological half-lives were approximated by a sum of two exponentials amounting to 3 (85%) and 15 (15%) days for 137 Cs and 3.5 (70%) and 100 (30%) days for 90 Sr. The highest 137 Cs transfer has been found to be to spleen, followed by lung, heart, muscles, kidneys, intestine, and finally skin and bones. For 90 Sr, the maximum activity concentration was observed in bones; contamination of other tissues is rather uniform except for liver and intestine with a factor of about 2 higher than muscles.

After the ChNPP accident a very large part of the territories covered by natural and artificial forests are contaminated with long-lived radionuclides, especially 137Cs. To protect people against exposure associated with forest contamination in the most affected regions of the NIS countries, countermeasures have been developed and recommended for the forest management. The paper presents a decision making framework to optimise forest countermeasures in the long term after the ChNPP accident. The approach presented is based on the analysis of the main exposure pathways and application of radiological, socio-economical and ecological criteria for the selection of optimal countermeasures strategies. Because of the diversity of these criteria modern decision support technologies based on multi-attributive analysis were applied. The results of the application of this approach are presented in a selected study area (Novozybkov district, Bryansk region, Russian Federation). The results prove and emphasize the need for a flexible technique to provide the optimised forest countermeasures taking into account radioecological, social and economic features of contaminated forests.

The transfer factor (TF) of radiocaesium from soil-to-Swiss chard ( Beta vulgaris var. cicla L.) was studied in two different characteristic allophanic soils (umbric andosol and dystric fluvisol) of the Lake Region, an important agricultural region situated in central-south Chile. To investigate especially the time dependence and the effect of K-fertilisation on the TF, field experiments were conducted. Plots of 7.6 m 2 were labelled with 100 kBq 134 Cs m −2 at Santa Rosa Experiment Station close to the city of Valdivia characterised by a temperate climate and high precipitation rates. The variation in time of the radiocaesium TF soil-to-Swiss chard was observed during two consecutive years after soil contamination by sequential harvests and radiocaesium analyses of the plants. The TFs showed no significant ageing effect, but a pronounced seasonal decrease with effective half-lives of about 140 and 160 days for the umbric andosol without and with K-fertilisation, respectively, and of 50 and 60 days for the dystric fluvisol without and with K-fertilisation, respectively. The effect of K-fertilisation on the absolute values of the TF was determined by the ratio between the median TF values obtained for corresponding dates without and with use of K-fertiliser. A ratio of TF without K TF with K =1.8 for the umbric andosol and TF without K TF with K =2.9 for the dystric fluvisol was obtained, indicating a reduction of the TF by applying 90 kg K ha −1 . The maximal values of the TF to chard predicted by the equation characterising the seasonal decrease of the TF at the beginning of the harvest periods are 0.19 for the umbric andosol and 0.11 for the dystric fluvisol, both values for soil treated with common K-fertilisation.

— The Semipalatinsk Test Site in Kazakhstan was one of the major sites used by the USSR for testing nuclear weapons for more than 40 y. Since the early 1990’s, responsibility for the site has passed to the Kazakh authorities. There has been a gradual re-establishment of agricultural use such as horse and sheep farming. Therefore, it has become important to evaluate the current and future risk to people living on and using the contaminated area. Internal dose assessment is one of the main components of the total dose when deriving risk factors for population living within the test site. Internal doses based on food monitoring and whole body measurements were calculated for adults and are in the range of 13–500 μSv y−1 due to radiocesium and radiostrontium.

External gamma exposures from radionuclides deposited on surfaces usually result in the major contribution to the total dose to the public living in urban-industrial environments. The aim of the paper is to give an example for a calculation of the collective and averted collective dose due to the contamination and decontamination of deposition surfaces in a complex environment based on the results of Monte Carlo simulations. The shielding effects of the structures in complex and realistic industrial environments (where productive and/or commercial activity is carried out) were computed by the use of Monte Carlo method. Several types of deposition areas (walls, roofs, windows, streets, lawn) were considered. Moreover, this paper gives a summary about the time dependence of the source strengths relative to a reference surface and a short overview about the mechanical and chemical intervention techniques which can be applied in this area. An exposure scenario was designed based on a survey of average German and Hungarian supermarkets. In the first part of the paper the air kermas per photon per unit area due to each specific deposition area contaminated by 137Cs were determined at several arbitrary locations in the whole environment relative to a reference value of 8.39 x 10(-4) pGy per gamma m(-2). The calculations provide the possibility to assess the whole contribution of a specific deposition area to the collective dose, separately. According to the current results, the roof and the paved area contribute the most part (approximately 92%) to the total dose in the first year taking into account the relative contamination of the deposition areas. When integrating over 10 or 50 y, these two surfaces remain the most important contributors as well but the ratio will increasingly be shifted in favor of the roof. The decontamination of the roof and the paved area results in about 80-90% of the total averted collective dose in each calculated time period (1, 10, 50 y).

The mission of the IAEA Laboratories is to contribute to the implementation of the Agency's programmes in food and agriculture, human health, physical and chemical sciences, water resources, industry, environment, radiation protection and safeguards verification.

The contamination and depth distribution of 137 Cs in soil due to the fallout from atmospheric weapons’ tests were measured at 29 sites in the 9th and 10th administrative regions in Chile located in the 40 ° latitude in the southern hemisphere. The depth distribution in most of the sites follows no systematic pattern in the upper few centimetres, but below this depth an exponential decline could be deduced. The calculated relaxation depth appears to be a good indicator for estimating the long-term 137 Cs distribution in these soil profiles. It ranges from 4.4±1.9 cm in Palehumults to 8.4±4.4 and 9.7±5.1 cm in Hapludands and Psamments, respectively. For these soil types the value for the relaxation depth tends to increase with decreasing clay content and increasing volume of coarse pores. 137 Cs activity densities at the selected sites ranged from 450 to 5410 Bq m −2 and correlate significantly ( r =0.791∗∗) with the mean annual rainfall rate of the sampling sites. 137 Cs concentration ratios of prairie plants/soil were found to be in the range 0.008–2.3 and could be related to relaxation depths in undisturbed soils.

To improve the knowledge about the (137)Cs spatial distribution and vertical migration in soils of the Southern Hemisphere, the total areal activity density and the vertical transport parameters of this radionuclide were measured in an Antarctic region. For this purpose vegetation and incremental soil samples were collected at 21 representative sites located at 4 islands of the South Shetland Archipelago: King George, Robert, Greenwich and Snow (62-63 degrees S and 58-62 degrees W). The total (137)Cs activity density varied considerably from 118 to 662 Bq m(-2) (median 384 Bq m(-2), reference date 1995), with a high percentage of the total activity retained in the vegetation cover (5-98% in moss, 3-20% in lichen and 4-12% in grass). At most sites, the maximum activity density in soil was observed in the top layer from where it decreased continuously. To evaluate the transport parameters of (137)Cs from the activity-depth profiles, the classical convection-diffusion model was used based on the time-course of the annual deposition density of (137)Cs at the studied region. The values for the diffusion coefficient D(s) (median 0.043 cm(2) year(-1)) and the convection velocity v(s) (median -0.012 cm year(-1)) of radiocesium observed under a polar climate are small compared to the transport parameters determined in temperate zones. The data also indicate that at these sites the convectional transport of (137)Cs is almost negligible compared to the transport by diffusion. The high vulnerability of the Antarctic soils to (137)Cs deposition, as a consequence of its very slow transport due to the extreme climatic conditions at these latitudes, has been confirmed.