Radiological Impact Assessment Research Articles

Assessment of Radiological Impact for Individuals Associated with Natural Occurring Radioactive Material in Ceramic Industry

Assessment of Radiological Impact for Individuals Associated with Natural Occurring Radioactive Material in Ceramic Industry

Assessment of background dose rate on non-human biota in a Mediterranean terrestrial ecosystem.

The assessment of radiological impact to the environment is usually carried out by the dose rate estimation to hypothetical entities named Reference Animals and Plants (RAPs). There are many codes to carry out this assessment, which requires the definition of a scenario and using site-specific transfer parameters when possible. Transfer parameters present a geographical bias, as they are mostly derived from temperate and arctic climate datasets, but there is a scarcity of data for Mediterranean climates. In this study, a terrestrial Mediterranean scenario was defined using the distribution of activity concentrations of anthropogenic (90Sr, 137Cs) and naturally occurring radionuclides (40K, 210Pb, 210Po, 226,228Ra, 235,238U, 232Th) in Cáceres province (Spain). Site-specific transfer factors, CRwo-media, defined as the ratio between the concentration in the whole organism and the medium (soil in this case) were considered. Dose rate assessments for terrestrial RAPs were carried out using Tier 3 in ERICA Tool, ranging 0.23-3.73µGy/h which is below the screening level of 10µGy/h. Therefore, no harmful effects are expected to occur. Internal dose rate predominates over external one because the main contributors are naturally occurring radionuclides (in most cases 40K, 226,228Ra, 210Pb, 210Po), which are mostly α-emitting radionuclides. These results can be used for the evaluation of other radiological and nuclear installations in Mediterranean climates, as they set the background dose rate.

Environmental Radioactivity Monitoring and Radiological Impact Assessment of Agbara Industrial Area, Ogun State, Nigeria

This study assessed the naturally occurring radioactivity of 40K, 238U, and 232Th, which pose a significant threat to human health, particularly when their concentrations exceed the threshold. Background radiation levels were measured at two specific locations, Access Bank and Market areas, across a total of forty (40) sample points. The measurements were taken using a calibrated RS125 Gamma Spectrometer (a portable NaI [Tl] detector) designed in Canada, in conjunction with a global positioning system (GPS) to accurately record the research coordinates within the Agbara industrial area, Ogun State, Nigeria. The mean activity concentrations of the primordial radionuclides were 177.87 Bqkg-1, 20.01 Bqkg-1, and 52.90 Bqkg-1 for 40K, 238U, and 232Th, respectively. More so, the in-situ measured dose rate (DR) ranges between 12.18 nGyh-1 (Access Bank area) and 97.95 nGyh-1 (Market area), with an average value of 47.22 nGyh-1. The average measured and estimated absorbed dose rates were within the safe limit of 57 nGyh-1 provided by UNSCEAR. However, the measured dose rates exceeded the recommended limit in ten locations, while measured activity for thorium exceeded the world average value for over half of the study locations. Although all estimated radiological parameters were within recommended threshold values, suggesting the low risk of exposure to higher levels of ionising radiation in most locations in the Agbara industrial area, there is a potential cancer risk for individuals who have resided in the area for 70 years or more due to long-term exposure to ionising radiation.

A review of radioactive waste processing and disposal from a life cycle environmental perspective

AbstractThe role of nuclear power in a more sustainable, ‘net zero’ energy sector is an important focal point of research. Given the large volume of existing legacy wastes and the future waste arisings that nuclear expansion would entail, attention is needed in the ‘back-end’ of the nuclear fuel cycle: processing (including treatment and conditioning) and disposal of radioactive waste. The range of waste processing techniques already in operation is broad and complex, and many novel technologies are under development. However, whilst prior work only focused on technology development and direct emissions, particularly in post-processing and disposal, a life cycle perspective is underutilised. This review analyses the landscape of life cycle assessment (LCA) within the nuclear sector, focusing on radioactive waste management, decommissioning and disposal. A literature search yielded 225 journal articles plus additional grey literature, yet only eight relevant LCAs were identified. Most studies identified adopted power generation as a functional unit and focused on nuclear power plants currently in operation. The major research gap identified in this review is the lack of holistic life cycle thinking surrounding radioactive waste management caused by poor granularity of published data related to waste treatment, conditioning and disposal, making strategic analysis challenging from the perspective of sustainability. Future LCA work should focus on technologies and processes in the back-end nuclear fuel cycle with considerable granularity to allow system ‘hotspots’ to be identified and strategic research and policy decisions to be taken. Efforts should also be made to incorporate recent developments in radiological impact assessment methodologies such as UCrad. Graphical abstract

Radiological impact assessment of a dirty bomb using Hotspot Code and AI: Insights from spent nuclear fuel isotopes

This study evaluates the potential radiological effects resulting from the use of a Radiological Dispersal Device (RDD), commonly known as a “dirty bomb,” in Dhamar City, Yemen, focusing on its impact on human health. Seasonal atmospheric variations were analyzed using the HotSpot Health Physics Code to model the Total Effective Dose Equivalent (TEDE) distribution following an explosion. The TEDE’s effect on different human organs was assessed, considering both external and internal radiation exposures. The study demonstrated that winter nights posed the highest radiation risk, with dose distribution areas of 0.018 km2, 0.14 km2, and 3.3 km2 for inner, middle, and outer zones, respectively, surpassing other seasonal and daily values. Conversely, summer recorded the lowest radiation spread. A detailed temporal analysis during winter nights showed an initial TEDE of 9.5 Sv at 0.1 min post-explosion, which decreased exponentially to 1.3 Sv after 2000 min (33.3 h) and further to 0.0038 Sv after 6500 min (108.3 h) with the aid of AI-enhanced “Long Short Term Memory Networks (LSTM)”. The highest radiation doses to human organs within a 100 m2 area during the initial 10 min post-detonation were significantly above permissible limits, with critical organs like the surface bone, liver, and red marrow receiving doses of 68 Sv, 12 Sv, and 5.5 Sv, respectively. These findings underline the need for robust emergency response strategies and long-term health monitoring to mitigate the adverse health impacts of RDDs. The comprehensive assessment presented in this study, enhanced by artificial intelligence, provides essential data for improving public health safety and emergency preparedness in regions susceptible to radiological threats.

Environmental Radiological Impact and Risk Assessment of Natural Radioactivity at the Heap Leach Facility of Tarkwa Goldmine, Ghana: Radiotoxicity and Public Exposure

In this study, a comprehensive investigation was conducted to determine the radioactivity levels of naturally occurring radioactive materials (NORMs) in heap pads/soil and water samples within and around the operational area of Tarkwa Gold Mine in Ghana. Gamma-ray spectrometry was used to determine the activity concentrations of 238U, 232Th, and 40K in heap pads/soil, and 226Ra, 228Th, and 40K in water samples. The average activity concentrations of 226Ra and 228Th in all water samples were below the World Health Organisation (WHO) recommended guidelines for drinking water. Similarly, the average activity concentrations of measured radionuclides in heap pads/soil samples taken from depths of 0–20 cm and 20–50 cm were found to be below the worldwide average reported values. The annual effective dose to the public was estimated to be around 0.16 mSv, which is below the recommended limit. The values of the hazard indices are also below the recommended limits, implying that if heap pads/soils are used for building purposes and construction, they will not pose any significant radiation hazard. The results of this study indicate that radiation levels are within the natural background radiation levels reported in the literature and are consistent with findings from similar studies conducted in Ghana.

Phytoremediation of radium contaminated soils: recent advances and prospects

Abstract Radioactive radium (Ra) mainly comes from the mining and milling of uranium and other metal or non-metal mines, phosphate production and fertilizer use, production of oil and gas, coal combustion, wastewater treatment, and various wastes from the above activities, which is ubiquitous in the environment. Phytoremediation is a green and cheap remediation technology for metal/radionuclide-contaminated sites. Radium is often of particular interest and there are many literatures on parameters of Ra concentration in plants and transfer factors from soil to plant from a radiological impact assessment point of view. However, review articles on phytoremediation of Ra-polluted soil are relatively few. This review focused on radium-polluted soil phytoremediation, involving two main strategies of phytoextraction and phytostabilization, which covered the potential (hyper)accumulators for Ra, characteristics of Ra uptake from soil by plants, influencing factors, and phytostabilization application. In future research works, more attention should be paid to the deep insights and mechanism researches of Ra uptake/immobilization by plants. This review will deepen the understanding of the relationship of radium-soil-plants, and to enhance the potential application of phytoremediation as an alternative treatment technology for remediation of Ra-polluted soil site.

Assessment of environmental radiological impact in former metallic mines in Extremadura (Spain): A case study

Metal mining in the Extremadura region was very important in the 19th and 20th centuries. However, due to different reasons the great majority of mines ceased operations, leading to plenty of abandoned mining sites, most of them with on-site waste dumps. Although metal extraction is not radioactive per se, it is considered a NORM activity. In this study, three former mining sites, in which Pb-V-Zn-Ag, Pb-Ag, and Pb-Zn were extracted, were selected to assess the radiological impact on the population and the environment. The external γ exposure was estimated by determining the effective dose and elaborating isodose maps of the sites. The presence of the mining sites increased up to 0.41 mSv/y the effective dose over the surrounding background, which is below the reference value of 1 mSv/y. In only one mining site, the uranium and radium activity concentration of waste dumps were higher than the surrounding soil. The soil to plant (wild grass) transfer factors were similar to other reported values without the influence of NORM activities. So, no enhanced transfer of radionuclides was observed. The radiological impact on the environment was assessed by the risk to non-human biota using the tiered approach developed in ERICA Tool. The sum of the risk quotients of all considered radionuclides in the most conservative Tier 1 was below 1. Total dose rates for several terrestrial Reference Animal and Plants (RAPs) were estimated using Tier 3, obtaining values below 40 µGy/h. Therefore, the impact on non-human biota can be considered as negligible.

Groundwater path radiological impact assessment for the derivation of specific clearance levels for landfill disposed waste at Ignalina NPP

Industrial waste generated from the operation of Ignalina NPP was disposed of in industrial waste dumps, the so-called “landfill facility”. At the time of disposal, the waste was considered as non-radioactive. Due to changes in the regulatory requirements, a part of the waste was reclassified to a very low-level radioactive waste. The Ignalina NPP final decommissioning plan foresees the development of specific clearance levels for the disposed of waste. Application of specific clearance would allow removal from regulatory control and conversion of the existing landfill into a conventional waste disposal facility.This paper focuses on the modeling of radionuclide release and dispersion by different groundwater pathways, calculation of associated radiological impacts and definition of specific clearance levels for the landfill facility disposed of waste. The radionuclides considered in the assessment are based on the waste specific and include 3H, 60Co, 94Nb, 137Cs and 241Am. Modeling is performed using GOLDSIM software.

Radiological Impact Assessment of Soil and Rock Samples in Underground Goldmine

Radiological Impact Assessment of Soil and Rock Samples in Underground Goldmine

Assessment of radiological environmental impact under various meteorological condition

The meteorological parameters, e.g., wind direction, wind speed and atmospheric stability, affect greatly the diffusion of pollution and radiological environmental impact assessment. Based on the hourly meteorological data obtained from an automatic monitoring station, the radiological impact indicated by the air concentration, individual dose and maximal individual effective dose were analyzed and compared between 2020 and 2021. The paper concluded that children are the main group to be the most easily infected, and the critical exposure path is internal exposure from inhalation. This paper offers a new window for timely decision-making for radiological safety under different climate conditions.

Natural radioactivity analysis and radiological impact assessment from a coal power plant

Natural radioactivity analysis and radiological impact assessment from a coal power plant

Environmental Modeling for Radiation Safety

The newly launched IAEA project MEREIA (MEthods for Radiological and Environmental Impact Assessment; 2021- 2025), MEREIA continues some activities of previous IAEA exercises in the field of radioecological modelling and focuses on areas where the probabilistic approach determines the predictive capability of environmental models. The program offered the opportunity to set up well-designed and verified scenarios to collect and compare exposures predicted by particular models based on this scenario and then perform a validation study of contributing models. It consists of the comparison of model prediction with observed data or in the case where there is a lack of measurement data to perform a comparison within model prognoses. The previous international works have brought significant improvement in environmental modeling in terms of better understanding and mathematical description of complex physical and chemical phenomena that occur in various environmental media and also have promoted new areas for experimental investigations. The new experimental results yielded updated handbooks of a large number of environmental parameters for less-known elements. Moreover, the principal objective of the activities in environmental modelling was an integrated risk assessment of the reference group of population and biota associated with radionuclides releases from various kinds of nuclear facilities as from different types and power nuclear reactors, radioactive waste disposal and more complex nuclear research facility. This reflects recent international recommendations to extend protection against radiation hazards of humans to wildlife flora and fauna. However, the statistics supported knowledge on some essential environmental parameters still remain small. Therefore, one could be aware of some limitations of the probabilistic approach that required advanced methods of probabilistic prognosis Monte Carlo.

Comparison of methods for the radiological impact assessment of aquatic releases to the waters in the low countries

Accurate assessment of the radiological impact of liquid discharges on the marine environment is challenging despite all developments in recent years. The lack of consensus on this type of assessment manifests itself even stronger when transborder issues are expected, such as in the Low Countries. Belgium and the Netherlands operate nuclear power plants with discharges in the shared estuary of the Western Scheldt, therefore if there are safety concerns, information on both sides of the border must be coherent. This work provides a comparison of two computational methods used for assessment of aquatic releases in the Western Scheldt estuary and the adjacent North Sea.The work demonstrates a fair degree of consistency in modelling the uptake and fate of key anthropogenic radionuclides. Nevertheless, there are also considerable differences found in sediment and sea species with concentrations ranging by over two orders of magnitude in some cases. These explainable differences are methodological in nature, occurring in codes that underwent extensive validation during development. Therefore, the outcomes of this work clearly demonstrate the need to produce explicit guidance that is specifically tailored to the (inter)national water system of concern. This should not be limited to releases from nuclear power plants, but also include other nuclear applications. For all these reasons, more intensive collaboration and model harmonisation across borders is essential, signalling the direction for future investigations.

Radiological Impact Assessment of Acute Tritium Releases in Environment—A Soil Dynamic Model

Radiological and environmental impact assessment models are important tools that support nuclear safety. The present study summarizes the upgrades of a research-grade model (CROPTRIT) with an emphasis on a soil submodel and the balance between air-to-plant and soil-to-plant pathways, together with the needs that must be accomplished by an operational model in order to be applied to nuclear facilities involving large tritium loads.

The NERIS roadmap: research challenges in emergency preparedness, response and recovery

NERIS as a European Platform on Preparedness for Nuclear and Radiological Emergency Response and Recovery (EPR&R) has developed a roadmap setting out the key research challenges for radiation emergency preparedness, response and recovery. Research projects in this field have been summarised to demonstrate how important areas of development have been identified and addressed. Radiation EPR&R has a continuous need to evolve to meet societal demands, but also to keep pace with scientific and technological developments and opportunities and so the NERIS research priorities as published in the Strategic Research Agenda (SRA) are kept under review. Three challenge areas have been identified covering the topics of radiological impact assessment, protective action strategies and establishing a transdisciplinary and inclusive framework for emergency preparedness, response and recovery. The importance of these challenge areas and the underlying key topics for NERIS have been mapped across to the Joint Radiation Protection Roadmap developed by the consortium of European radiation research platforms known as MEENAS. The war in Ukraine triggered a new round of revision of the SRA that resulted in the identification of four topics as new or revised challenges for the NERIS community. These updated challenges are: (1) optimisation of management strategies for the transition and recovery phase, (2) uncertainty quantification, data assimilation and monitoring strategies, (3) inverse modelling, and (4) lessons identified from Ukraine and implications for emergency preparedness. These four areas will form the priority research areas for the NERIS community to help advance radiation emergency preparedness to meet current challenges and needs that have been identified.

Assessment of radiological impact on the surrounding environment and biota for phosphogypsum waste stockyard in Korean facility.

In this study, the effects of deposited gypsum residues on the surrounding environment and radiation exposure in plants and animals were evaluated under various exposure situations. A waste stockyard in a Korean facility (surrounded by mountains and sea) was used to store phosphogypsum, a byproduct of phosphoric acid processes, in a slurry form in a large gypsum storage facility (provided separately on the facility site). The ERICA tool was used to evaluate the impact of radiation on nonhuman environments for mineral processing and waste storage for risk estimation. The impact of radiation on the environment due to the phosphogypsum stockyard was negligible with a screening dose of less than 10μGyh-1. However, to conservatively evaluate the environmental impact of rain and wind in the phosphogypsum stockyard, the soil at the interface of the stockyard, where plants could not grow, was considered as an input value, and the estimated dose rate of shrubs was found to be 45μGyh-1. The effects of the phosphogypsum stockyard on the surrounding environment accounted for 95-100% of the total dose for internal exposure in biota. In general, radium was found to be the highest contributor to biota, and the next lead and polonium were contributors to the dose. The findings contribute to an understanding of the radiological impact of waste stored and disposed of at the facility on the environment and biota (all routes of exposure) and to developing sustainable operations and pollution monitoring policies.

Assessment of marine radiological impact after an hypothetical nuclear accident in Eastern Mediterranean Sea

The consequences after an hypothetical nuclear accident at the Akkuyu Nuclear Power Plant in the region of Eastern Mediterranean Sea are presented. The dispersion of the radioactive plume in the sea is simulated applying a regional hydrodynamic/Lagrangian drift model and the radioecological impact is estimated after the release of 137Cs, 238Pu and 131I. The doses to marine biota and the human habitants of the affected regions are presented, while the sensitivity analysis of the results revile the most vulnerable features of this marine environment.

Assessment of the environmental radiological impact in the emergency exposure phase through the simulation of a uranium mining tailings dam breach

This work is aiming at estimating the radiation doses to members of the public in case of an emergency exposure situation related to a hypothetical uranium mining tailings dam rupture at the UDC - Decommissioning Unit of Caldas, MG, Brazil. The calculations will help to managing the exposures of emergency workers and residents in the region downstream the dam. The computer code chosen to perform the simulations was FLO-2D@ software. Due to the uncertainties involved, mainly regarding the waste rheology and activity concentrations and in parameters values to be used in the dose assessment, considerations were made for the study to present results derived from conservative assumptions. Through the creation of flood maps, it was possible to estimate the extent of the areas affected by the released materials. The results showed that in a scenario of the tailings dam breach, deposition of mud shall extend over 20 km downstream affecting an area of nearly 3 km2. Total dose for a member of the public living in most affected areas would be around 43 mSv/y in the early phase after the accident. Although only shielding would be recommended under current radiation protection regulation, evacuation/relocation is suggested due to the presence of long-lived radionuclides. This protective measure would probably already be indicated by the accident itself, regardless of radiological reasons. More realistic assessment should be performed before returning people, considering long-term environmental transport and uses of the area. It must also be considered that long-term exposures have more restricted recommended acceptable levels than those for the emergency phase.

Radiological impact assessment due to background ionizing radiation around palm oil processing mills in southwestern Nigeria

This study assesses palm oil processing mills' background ionizing radiation exposure rate and is radiological health hazards in various communities within Southwestern Nigeria. At the height of 1.0 m, a digital Geiger Muller counter measured the radiation exposure rate in forty-three selected palm oil processing mills. The recorded background radiation exposure rates during non-working hours were below the recommended acceptable limit, while the background radiation exposure rates during the working hours were higher than 0.013 mR.h-1, the recommended permissible limit provided by the International Commission on Radiological Protection. During the working hours of the palm oil processing mills, the estimated absorbed dose rates and excess lifetime cancer risks were all greater than the recommended acceptable safety limits. The estimated values of the effective dose irradiated to various body organs and tissues due to radiation exposure and inhalation in the designated palm oil processing mills during their working and non-working hours were lower than the allowable global limit of 1.00 mSv.y-1. This study showed that the study area is radiologically polluted; nevertheless, the pollution may not produce any immediate radiation hazards to the residents of the area.