Brazilian Journal of Radiation Sciences (BJRS)
Brazilian Journal of Radiation Sciences - BJRS ISSN 2319-0612 Una forma de impactar la cultura de seguridad y protección radiológica es establecer procesos de comunicación adecuados entre todos los actores involucrados en las aplicaciones de las radiaciones y en la protección radiológica. En este contexto, la BJRS como revista de acceso abierto, mantenida por la Sociedad Brasileña de Protección Radiológica - SBPR, sociedad asociada de la Asociación Internacional de Protección Radiológica (IRPA), tiene como objetivo difundir artículos científicos sobre las principales disciplinas de las ciencias de la radiación, entre ellas: • Efectos biológicos y en la salud de la radiación, • Protección radiológica de pacientes, trabajadores y miembros del público, • Mediciones de Radiación y Dosimetría, • Recomendaciones y Normas Internacionales, • Protección del ambiente, • Educación y entrenamiento, • Tecnología y Desarrollo, • Comunicación con la Sociedad, • Compromiso y Participación de las Partes Interesadas, • Cultura de Seguridad y Percepción de Riesgo, • Preparación y respuesta ante emergencias, • Gestión de Residuos Radiactivos, • Transporte Seguro de Materiales Radiactivos, • Seguridad Nuclear, Salvaguardias y Seguridad de los Materiales Radiactivos, • Derecho Nuclear, • Tecnología de Reactores Nucleares: nuevos conceptos, • Ciclo del Combustible Nuclear.
Sociedade Brasileira de Proteção Radiológica
Licencia: los artículos de BJRS tienen una licencia internacional Creative Commons Attribution 4.0, que permite el uso, el intercambio, la adaptación, la distribución y la reproducción en cualquier medio o formato, siempre que se otorgue el crédito correspondiente al autor o autores originales y a la fuente, proporcione un enlace a la licencia Creative Commons e indique si se realizaron cambios. Las imágenes u otros materiales de terceros en el artículo están incluidos en la licencia Creative Commons del artículo, a menos que se indique lo contrario en una línea de crédito al material. Si el material no está incluido en la licencia Creative Commons del artículo y su uso previsto no está permitido por la regulación legal o excede el uso permitido, el autor deberá obtener el permiso directamente del titular de los derechos de autor. Para ver una copia de esta licencia, visite http://creativecommons.org/licenses/by/4.0/
The Standardization of Cone Beam Computed Tomography (CBCT) Presets on the Elekta XVI System for Optimized Image-Guided Radiotherapy (IGRT)
Image-Guided Radiotherapy (IGRT) relies on accurate imaging systems to ensure precise patient positioning and target localization. Cone-Beam Computed Tomography (CBCT) integrated into the Elekta XVI platform enables volumetric imaging with soft-tissue visualization, but image quality and patient dose strongly depend on acquisition parameters, or “presets.” This study presents a comprehensive methodology for standardizing CBCT presets on the Elekta XVI system to optimize image quality, geometric accuracy, and radiation dose according to the ALARA (As Low As Reasonably Achievable) principle. Eighteen acquisition configurations were systematically evaluated by varying tube potential, tube current, exposure time, filtration, collimation, gantry speed, and projection number. Radiation dose was measured using a calibrated ionization chamber, while image quality was assessed through Catphan 503 phantom analysis using the PyLinac software, quantifying uniformity, contrast-to-noise ratio (CNR), spatial resolution (MTF), and geometric accuracy. Results showed that tube potential (kV) was the dominant factor influencing image uniformity (ρ = 0.674, p = 0.0229) and contrast (ρ = 0.676, p = 0.0225), while dose scaled linearly with tube current and exposure time. Bow-tie filtration (F1) reduced central dose by approximately 25% and improved CNR. Geometric accuracy remained within ±1 mm for all protocols. Based on these quantitative relationships, standardized clinical presets were established for distinct anatomical sites (Head and Neck, Chest, Prostate and Pelvis), combining higher tube potential with reduced mAs to balance photon penetration, image contrast, acquisition time, and dose efficiency. The resulting protocols ensure reproducible image quality, and minimized patient exposure. This framework demonstrates that data-driven standardization of CBCT presets enhances both safety and precision in daily IGRT practice and provides a foundation for future adaptive radiotherapy integration.
Derechos de autor 2026 Victor Augusto Bertotti Ribeiro, Hélio Yoriyaz https://creativecommons.org/licenses/by/4.0
Patient-Specific Quality Control (PSQA) of stereotactic treatments in radiotherapy: a study of the sensitivity of a commercial in-vivo dosimetry system
This study evaluates a commercial automated in-vivo dosimetry software for stereotactic radiotherapy, focusing on its sensitivity to variations and accuracy in dose prediction. Development: The system’s sensitivity was assessed through linear accelerator performance tests, detecting both natural and intentionally introduced errors. Methods: The research was divided into two parts. In Part A, the system’s sensitivity was tested by assessing output constancy and linearity for different field sizes. A homogeneous phantom simulated static fields, allowing the introduction of controlled discrepancies, including geometric shifts, multileaf collimator (MLC) deviations, and energy variations. Part B used a heterogeneous phantom replicating human head and neck anatomy to simulate realistic stereotactic radiotherapy plans with varying targets and doses. These plans were intentionally modified before irradiation and delivered to an electronic portal imaging device. Planned and delivered dose distributions were compared using gamma index criteria. Results: Output linearity tests showed improved gamma passing rates with higher dose deliveries, while larger fields exhibited degraded rates due to steep dose falloff at field borders. The 3%/3mm criterion was ineffective for low-dose segments. For output constancy, gamma passing rates improved with stricter 2%/2mm and 1%/1mm criteria as dose decreased, whereas the 3%/3mm criterion remained insensitive. The system effectively detected intentional output variations, though sensitivity dropped for dose differences below 5%. It identified field size variations up to 1 mm and collimator rotations up to 5°, with MLC discrepancies detectable up to 1 mm. Among the tested criteria, 3%/3mm proved least robust. Energy variations were accurately detected. Tests with the heterogeneous phantom confirmed the platform’s ability to verify planned treatment parameters and dose metrics accurately. Conclusion: The study provided a comprehensive assessment of stereotactic treatment plan quality. The evaluated platform demonstrated strong capability to detect performance variations, geometric and MLC errors, and energy discrepancies, ensuring confidence in the quality assurance process. The findings support avoiding the use of permissive gamma criteria such as 3%/3mm in stereotactic treatments, as they provide limited insight into plan quality.
Derechos de autor 2026 Mardey Santana Silva, Dra. Simone C. Cardoso https://creativecommons.org/licenses/by/4.0
Gestión y desafíos del tratamiento del cáncer de tiroides con terapia con yodo radiactivo en un paciente con parálisis cerebral y trastorno del espectro autista: un informe de caso
El cáncer de tiroides es una de las neoplasias endocrinas más prevalentes en Brasil, y la terapia con yodo radiactivo (RAI) es un enfoque terapéutico adyuvante bien establecido. Sin embargo, el manejo de este tratamiento puede ser un desafío en pacientes con trastornos neurológicos y alteraciones conductuales. Este informe de caso describe la experiencia de un adolescente de 16 años con parálisis cerebral y trastorno del espectro autista (TEA) de nivel 3, que se sometió a RAI tras una tiroidectomía total debido a un carcinoma papilar de tiroides metastásico. El caso resalta el enfoque técnico personalizado adoptado por los profesionales de la salud para abordar las demandas específicas de este escenario complejo. Este caso pone de relieve la complejidad de la RAI en pacientes con discapacidades neurológicas graves y refuerza la necesidad de una participación multidisciplinaria ampliada, incluyendo neurólogos y psiquiatras, durante la fase preparatoria. La implementación de una capacitación ampliada para cuidadores y la consideración de estrategias terapéuticas alternativas son esenciales para garantizar una mayor seguridad y adherencia al tratamiento.
Derechos de autor 2026 Dra. Janaína Dutra Silvestre Mendes, Beatriz Trajano Coelho, Claudia Maria Teixeira Palhota Menezes, Marcia Maria Santos Lopes de Andrade, Célia Helena Fernandes da Costa https://creativecommons.org/licenses/by/4.0
Monte Carlo simulations study of non-collinear gamma-ray cascade correlation emissions for medical imaging
Conventional imaging techniques such as SPECT and PET cannot directly identify the positions of individual decaying nuclei. As such, they heavily rely on statistical backprojection for image point reconstruction. Therefore, this study explores an alternative approach using non-collinear gamma-ray cascade emissions, which are emitted directly from the decay position and unaffected by positron movement. Detecting these cascades in coincidence allows precise localization of decay events, enabling direct image point reconstruction. To evaluate this concept, GATE Monte Carlo simulation was used to simulate the cascade emission from 111In-ion point sources and detection using collimated small animal PET scanner. Finally, a custom image reconstruction algorithm was developed to estimate the three-dimensional position of a decaying nucleus by calculating the midpoint of the shortest segment, or the intersection, between two collimator projections from a valid coincidence event. The results show that at the center of the field of view, image sensitivities of 22.2 cps/MBq in air and 20.0 cps/MBq in a PMMA phantom were achieved. Furthermore, a spatial resolution of 4.1 mm FWHM was obtained in the transaxial direction and 7.6 mm FWHM in the axial direction. The imaging system is capable of resolving two-point sources separated by 8.0 mm (transaxial) and 10.0 mm (axial). The results from this simulation study indicate that the proposed imager with its image reconstruction method surpasses conventional PET and SPECT in emission point localization accuracy.
Derechos de autor 2026 Leonid Leopold Nkuba, Innocent Jimmy Lugendo https://creativecommons.org/licenses/by/4.0
Metrology in the context of ionizing radiation regulatory bodies
This paper analyzes the role of metrology in the regulation of activities involving ionizing radiation in Brazil, highlighting its relevance in ensuring the reliability of measurements used in regulatory processes. The regulation of these activities is carried out by different governmental bodies, particularly the National Nuclear Safety Authority (ANSN), the Brazilian Health Regulatory Agency (ANVISA), and the Ministry of Labor and Employment, and is based on three main stages: the establishment of standards and regulations, licensing and authorization processes, and inspections and audits. In all these stages, metrology plays a central role by ensuring comparability and traceability of measurement results. The paper also discusses the integration of the Brazilian metrological infrastructure into the international context, emphasizing the importance of institutions and agreements such as the BIPM, ILAC, OIML, and the CIPM MRA, which are responsible for ensuring the international recognition of measurement standards and results. At the national level, the role of the National Institute of Metrology, Quality and Technology (INMETRO) is highlighted as the body responsible for coordinating the Brazilian metrological system, as well as the role of the National Laboratory of Ionizing Radiation Metrology (LNMRI) as the designated laboratory for ionizing radiation. In addition, the paper analyzes the operational measurement infrastructure in Brazil, which includes calibration laboratories, testing laboratories, individual monitoring services, and radiometric analysis laboratories, all linked to accreditation networks coordinated by Cgcre/Inmetro and CASEC. In this context, the reliability of measurements depends on metrological traceability to the International System of Units (SI) and on the proper integration of the different levels of the metrological infrastructure. Finally, it is concluded that although Brazil has a robust metrological infrastructure aligned with international standards, there is still no evidence that the installed capacity is sufficient to fully meet national demand. Therefore, the need for systematic assessments of the existing infrastructure and for strengthening actions aimed at ensuring metrological traceability and radiological safety in the country is emphasized.
Derechos de autor 2026 Paulo Gonçalves da Cunha, Eliana Correa Simões do Amaral https://creativecommons.org/licenses/by/4.0
Application of Optically Stimulated Luminescence Dosimeters in the Evaluation of the Dose Map Software in Interventional Radiology
Interventional radiology is widely employed; however, the complexity and duration of certain procedures may result in significant radiation exposure to patients. This study presents a comparison between a commercial computational dose mapping method used in interventional radiology, Dose Map, and optically stimulated luminescence dosimetry using a matrix built with these dosimeters. The dosimetric material was obtained from a roll of Landauer Luxel® tape and calibrated on a GE® Innova 4100 IQ angiography system, using an ionization chamber as a reference. The calibration yielded a linear relationship between the readout signal and the air kerma. Experiments were conducted using homogeneous poly(methyl methacrylate) phantoms, as well as clinical monitoring of patients. The maximum deviation between kerma values measured by the dosimeters and those estimated by Dose Map was 14%. The comparison among the dosimeter matrix, radiochromic film, and Dose Map demonstrated good geometric agreement in both phantom studies and patient monitoring. These results confirm the applicability of Dose Map for real-time dose monitoring, contributing to improved patient safety in interventional radiology.
Derechos de autor 2026 Eduardo Souza Santos, Denise Yanikian Nersissian, Elisabeth Mateus Yoshimura https://creativecommons.org/licenses/by/4.0
Practical leak detection and leak rate measurement applied to a hot cell for radiopharmaceuticals preparations in a GMP compliant Laboratory
Hot cells are containment systems used in radiopharmaceutical production, designed to ensure radiation protection and product quality. Leak tightness testing is a mandatory requirement under CNEN NN 6.13 standard, as it directly impacts worker safety, environmental protection, and product integrity. This study aimed to perform a practical pressure change leak test in a hot cell used for radiopharmaceutical preparations, in accordance with applicable technical standards. The pressure change method was applied using pressures between 1.6 and 2.5 higher the working pressure for a testing time of 15 minutes. The method proved practical, requiring no highly specialized equipment, although its sensitivity to temperature highlights the importance of high-precision thermometer. Results showed that while the method is suitable for ISO 10648-2:1994 Class 2 compliance, it may not be adequate for Class 1 due to the risk of mathematically inaccurate results under temperature variations. Multiple rounds of leak detection and repair were required to achieve the required containment level. Overall, the DC, RIC, CIC, and Solid Waste chambers met Class 2 leak tightness requirements, being suitable for use in radiopharmacy facilities.
Semana Nacional de la Ingeniería Nuclear y Energética y de las Ciencias Radiológicas (SENCER)
Derechos de autor 2026 Rodrigo da Silveira Santos, Carlos Leonel Zapparoli, Joel Mendes dos Santos, Gabriela Franco da Rosa Caetano, Marcelo de Gusmão Paraíso Cavalcanti, Delvonei Alves de Andrade https://creativecommons.org/licenses/by/4.0
PLA-Based Simulator for Dosimetry Assessment of Healthcare Waste
Healthcare waste (HCW) requires efficient treatment prior to final disposal to prevent the spread of pathogens and environmental contamination. Ionizing irradiation has emerged as a promising alternative to incineration; however, accurate absorbed-dose determination depends on knowledge of the material’s radiological properties. This work aims to develop a physical simulator for HCW to support dosimetric evaluation of irradiated waste, including experimental and computational validation. Data from the National Institute of Standards and Technology (NIST), along with the XCOM and ESTAR programs, were used to obtain mass energy-absorption coefficients for photons and mass stopping power for electrons in the energy range of 0.1 to 20 MeV. Two approaches were considered: a full compositional model representative of typical HCW, and a simplified model based on Polylactic Acid (PLA), containing only C, O, and H, assuming that PLA adequately reproduces the predominant elemental fraction of the waste. Dosimetric validation was performed by comparing mass attenuation coefficients (μ) and stopping power (S) between HCW and PLA. Computational simulations using PHITS evaluated the spatial dose distribution from photons and electrons. A physical simulator was subsequently manufactured by 3D printing in PLA, with a density of 0.15 g/cm³ and internal hexagonal geometry to reflect realistic waste packing characteristics. Comparisons of attenuation and stopping power coefficients showed minimal differences between HCW and PLA, demonstrating radiological equivalence. Simulations and analyses confirmed that the simulator effectively reproduces the spatial dose distribution, with good homogeneity and fidelity to real behavior. The use of PLA proved to be a practical, economical, and technically consistent solution for constructing simulators aimed at improving dosimetric processes in ionizing radiation treatment of healthcare waste, while also enabling reproducible studies with strong potential for practical application.
The Meeting on Nuclear Applications (ENAN)
Derechos de autor 2026 Hugo Leonardo Lemos Silva, Noil Amorim de Menezes Cussiol, Tarcísio Passos Ribeiro de Campos https://creativecommons.org/licenses/by/4.0
Radiotherapy in Prostate Cancer Management in Ceara, Brazil: A Descriptive Analysis of Utilization and Challenges
Prostate cancer remains a major public health concern in Brazil due to its high incidence and persistent regional inequalities. Early diagnosis is crucial for effective curative treatments, including radiation therapy; however, socioeconomic and geographic disparities significantly influence access to timely diagnosis and appropriate care. This study presents a descriptive analysis of prostate cancer management in Ceará, Northeastern Brazil, focusing on radiotherapy modalities and associated challenges. A retrospective review of 1,031 medical records from patients treated at the Integrated Regional Oncology Center (CRIO), in Fortaleza, between 2014 and 2023 was conducted. Data on demographic characteristics, disease staging, and treatment protocols were systematically analyzed, with emphasis on radiotherapy. Statistical analyses included Chi-square tests, Kruskal-Wallis tests, and multinomial regression to assess associations between patient characteristics, staging, and treatment decisions. Ethical approval was obtained (Protocol 4310688, Plataforma Brasil), with waiver of informed consent due to the retrospective design and use of de-identified data. The mean patient age was 71.3 years. Most patients were diagnosed with localized (Stage IIB, 36.3%) or locally advanced disease (Stage III, 23.2%), although a considerable proportion presented with Stage IV disease (16.0%). External Beam Radiotherapy (EBRT) was the predominant initial treatment (320 patients), whereas brachytherapy was used in less than 1% of cases. Geographic disparities were evident: 52.5% of patients came from Greater Fortaleza, reflecting centralization of oncology services. Educational attainment was generally low, with 21.5% illiterate and 63.5% having only elementary education, which may contribute to delayed diagnosis. A significant inverse association between age and disease stage (p<0.001) indicated that older patients were more frequently diagnosed at earlier stages, while younger patients tended to present with more advanced disease. Overall, the findings reveal systemic barriers to early detection and equitable treatment. The heavy reliance on EBRT, limited availability of brachytherapy—partly due to lack of domestic source production—and centralized oncology infrastructure highlight the need for improved regional planning, expanded radiotherapy capacity, and targeted strategies to reduce disparities within the public health system.
Derechos de autor 2026 Tainá Maria Travassos Mota Martins, Carla Daruich de Souza https://creativecommons.org/licenses/by/4.0
The sand extraction plays a crucial role in economic development and the construction industry. However, the fine waste generated during the extraction process brings environmental impacts on this activity. In order to promote the reuse of this waste, the synthesis of geopolymers was proposed. Geopolymers are a class of inorganic materials composed of aluminosilicates arranged in a three-dimensional network, originally developed by Joseph Davidovits in 1978. These are silica–alumina materials with an amorphous to semi-crystalline three-dimensional structure, obtained through alkaline activation. The raw materials used for their synthesis can consist of natural sources of aluminosilicates or by-products from industrial processes, which react through an alkaline activation route, generally using sodium or potassium hydroxide and silicate solutions as activating agents. These materials can be applied in the treatment of liquid radioactive waste through the sorption of cesium, which is commonly present in such waste. The study involved the characterization of mining waste, including quantitative (mineralogical) and qualitative (degree of amorphization) analyses, followed by the synthesis of the geopolymer. After 28 days of curing, the material was ground in a jaw mill and further reduced in a pulverizing mill. Cesium sorption tests with the prepared material were then carried out. The ground geopolymer was characterized by FTIR (Fourier Transform Infrared Spectroscopy), XRD (X-ray Diffraction), XRF (X-ray Fluorescence), particle size analysis, and BET surface area measurement. Cesium sorption tests (using inactive CsCl) were performed using the batch equilibrium method, as described in the EPA Method 530. The results demonstrated that the grinding process was effective in adjusting grain size, enhancing the material’s surface area. Mineralogical characterization confirmed the presence of aluminosilicates such as kaolinite and muscovite, which have favorable sorption properties. Thermal analysis identified the temperature range at which the material reaches a stable chemical composition, as well as the regions associated with dehydration and dihydroxylation. The tests indicated that the geopolymer obtained from sand extraction waste showed high cesium sorption potential, as evidenced by the sorption isotherm results.
Derechos de autor 2026 juniara versieux, Carolina Braccini Freire, Fenando Soares Lameiras https://creativecommons.org/licenses/by/4.0
Advances of the Modified Spectral Deterministic method applied in the solution of two-dimensional neutron shielding problems considering linearly anisotropic scattering
This work extends the application of the spectral-nodal method SDM, cf., Modified Spectral Deterministics (MSD-CN), to solve neutron shielding problems (fixed-source) in two-dimensional Cartesian rectangular geometry, considering problems with linearly anisotropic scattering in the formulation of discrete ordinates (<!-- [if gte msEquation 12]><m:oMath><m:sSub><m:sSubPr><m:ctrlPr></m:ctrlPr></m:sSubPr><m:e><m:r>S</m:r></m:e><m:sub><m:r>N</m:r></m:sub></m:sSub></m:oMath><![endif]--> <span style="font-size: 11.0pt; line-height: 107%; font-family: 'Calibri',sans-serif; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: 'Times New Roman'; mso-fareast-theme-font: minor-fareast; mso-hansi-theme-font: minor-latin; mso-bidi-font-family: 'Times New Roman'; mso-bidi-theme-font: minor-bidi; position: relative; top: 3.0pt; mso-text-raise: -3.0pt; mso-ansi-language: PT-BR; mso-fareast-language: PT-BR; mso-bidi-language: AR-SA;"> ), using a constant approximation for the transverse neutron leakage terms. The essence of this methodology lies in the use of the intranodal analytical solution of the neutron transport equation and an iterative process that employs the concept of spatial sweeping, like the Source Iteration method used in the fine-mesh method DD, cf., Diamond Difference, for estimating the angular neutron fluxes emerging in the spatial nodes. To validate the methodology, a numerical simulation of two model-problems was performed, where the MSD-CN was able to achieve numerical results with a small relative deviation compared to the reference method Diamond Difference alongside a performance test to compute the execution time of the algorithm. All methods were implemented in the computational language C++.
Meeting on Nuclear Reactor Physics and Thermal Hydraulics (ENFIR)
International Radiation Protection Association (IRPA)
Derechos de autor 2026 Rafael Barbosa Libotte, Hermes Alves Filho, Fernando Carvalho da Silva https://creativecommons.org/licenses/by/4.0
Analysis of the principles of green chemistry in the radioiodination of metaiodobenzylguanidine compared to the principles already adopted for radiological protection
Environmental concerns have increasingly highlighted the importance of applying methodologies that prioritize safer waste treatments, the use of less toxic reagents, and milder synthesis conditions. In this context, radioiodinated metaiodobenzylguanidine (MIBG) stands out as a key radiopharmaceutical used in diagnostic scintigraphy and therapy of neural crest-derived tumors, such as pheochromocytoma and neuroblastoma, as well as in assessing sympathetic neuronal integrity after cardiac events. Halogenation reactions that avoid toxic reagents and hazardous conditions are essential for producing safe pharmaceutical compounds. Radioiodination, a specific type of halogenation, plays a critical role in the synthesis of radiopharmaceuticals—radioactive compounds formulated for diagnosing and treating human diseases. A major challenge in the production of radioiodinated MIBG is aligning the process with the principles of green chemistry, emphasizing the use of harmless substances and minimizing their quantities, while also meeting stringent nuclear, radiological protection, and pharmaceutical regulations. However, green chemistry considerations are often neglected in this process. This study quantitatively assesses the application of green chemistry principles to existing radioiodination methods for MIBG. The degree of compliance with each principle was expressed as a percentage. Additionally, a qualitative analysis was conducted to explore the alignment between green chemistry and radiological protection principles. Green chemistry is guided by twelve principles: Prevention, Atom Economy, Less Hazardous Chemical Syntheses, Designing Safer Chemicals, Safer Solvents and Auxiliaries, Energy Efficiency, Renewable Feedstocks, Reducing Derivatives, Catalysis, Design for Degradation, Real-Time Analysis for Pollution Prevention, and Inherently Safer Chemistry for Accident Prevention. This work examines how each principle applies to MIBG radioiodination, with some aspects also discussed in the broader context of radiopharmaceutical production. While radioiodinated MIBG complies fully with pharmaceutical requirements in its final medicinal formulation, its production currently incorporates about 68% of the green chemistry principles. As radiopharmaceutical production moves forward, greater attention should be given to eco-friendly practices. Investing time and resources into adopting green principles for MIBG radioiodination is a logical next step. This radiopharmaceutical holds well-established clinical importance, and future advances in its production should embrace sustainable, environmentally conscious methodologies.
International Joint Conference Radio (RADIO)
Derechos de autor 2026 Antonio Pedro Junior, Eliene Bezerra Simão da Silva, Francisco José de Oliveira Ferreira, Rogerio Chaffin Nunes, Karine Rocha Ramos da Silva, Larissa Cunha Pinheiro, Fellipe Souza da Silva, Luciano Moreira Lima, Adriana Marques, Cintia Andrade Custódio, Luciana Carvalheira https://creativecommons.org/licenses/by/4.0
Application of Feedforward Neural Networks for Virtual Sensor Implementation in Nuclear Reactors
This study builds on a line of research developed at the Nuclear and Energy Research Institute (IPEN), focused on the use of Artificial Neural Networks (ANNs) to provide sensor redundancy in nuclear reactors. The proposed methodology consists of training a Feedforward Neural Network (FFNN) to estimate the value of one reactor variable based on measurements from other variables. The feasibility was demonstrated using data from IPEN’s nuclear research reactor and a scaled model. While previous works relied on data from a single operating cycle of the reactor, this study tested network performance using data from multiple cycles to assess accuracy and generalization, and to identify deficiencies in the method. One fault-free cycle was selected for training and validation, while five others were used for testing, featuring different events. Three temperature variables, three radiation variables, one power measurement, and one safety rod position were chosen as output sensors for the ANNs to estimate. Performance was evaluated using the Mean Absolute Percentage Error (MAPE). All ANNs performed well during training. However, only two temperature variables were estimated across all the test cycles with similar accuracy as in the training and validation process, with MAPE values below 3%. Other ANNs performed poorly, with instances of persistent offsets or failure to track the general shape of the measured signals. The results underscore the challenges posed by strong input-output correlations and the difficulty in capturing the full complexity of functional relationships within reactor variables.
Derechos de autor 2026 Frederico Emidio Wu, Thadeu das Neves Conti https://creativecommons.org/licenses/by/4.0
Committed Effective Dose by Ingestion Food Grown in PEPB
Radionuclides can be incorporated through ingestion and within the human body, they become a source of internal exposure. Therefore, identifying and quantifying the radionuclides present in food is an important step in environmental monitoring and radiological protection. From this perspective, the activity concentrations of 40K, 226Ra, 228Ra and 228Th were calculated for six organic crop samples: avocado, cabbage, carrot, persimmon, pineapple and onion, from the PEPB (stands for Pedra Branca State Park), Conservation Unit. Radionuclide analysis was conducted using gamma spectrometry with the use of a High Purity Germanium (HPGe) detector in conjunction with the Genie 2000 software package. The activity concentrations of the radionuclides were calculated based on simulated detection efficiencies. The highest activity concentration of 40K was obtained for the carrot (101.83 ± 15.47) Bq.kg-1, and the highest effective dose value, 1.64 µSv.year-1, was obtained for avocado. The concentration of 226Ra activity was below the minimum detectable activity in all samples. Concentrations of 228Ra were only detected in cabbage and carrots. Activity concentrations of 228Th were detected in all samples, although at low levels. Estimated ingestion doses are within the limits established by the ICRP 119. Thus, the consumption of these organic foods grown in the PEPB is radiologically safe.
Derechos de autor 2026 Nadia Rodrigues dos Santos, Alessandro Mariano Domingues, Izabella Soares de Souza, Carlos Omar Pastrana Orejuela, Rosa Jimenez Bermudez, Ademir Xavier da Silva, Edmilson Monteiro de Souza, Inayá Corrêa Barbosa Lima https://creativecommons.org/licenses/by/4.0
Influence of dose rate on radiotherapy treatment of the U87MG cell line through cell viability
Glioblastoma multiforme is a tumor that affects glial cells and is common in humans, being the most aggressive of gliomas. Patients, after diagnosis, have an average survival of just over a year, even when undergoing standard treatment. Given the low estimated survival of patients with this type of tumor, the objective of the study is to investigate the contribution of dose rate in radiotherapeutic treatment using a human glioblastoma cell line called U87MG, through the MTT (brometo de 3-[4,5-dimetiltiazol-2-il]-2,5-difenil tetrazólio) cell viability assay. Three dose rates were tested, including 400 cGy/min which is used clinically in patients, as well as 1.400 and 3.300 cGy/min from a clinical linear accelerator. Sterile culture plates with U87MG cells were irradiated, then, manipulated in the laboratory for the execution of the cell viability assay. The irradiated plates showed lower cell viability than the non-irradiated group, but there was no significant difference in viability among the different tested dose rates.
Derechos de autor 2025 Arthur Rocha, Ruy Rayol Neto, Debora Assis Carneiro, Delano Valdivino Batista, Luiz Antonio Ribeiro da Rosa, Mariana Paranhos Stelling, Simone Coutinho Cardoso https://creativecommons.org/licenses/by/4.0
Re-characterization of pneumatic station position for short irradiations of IEA-R1 reactor for use in k0-method
This work presents the re-characterization of pneumatic station irradiation position of IEA-R1 reactor for use in k0-INAA method. The thermal-epithermal neutron flux ratio f and the epithermal neutron flux distribution factor α of the IPEN IEA-R1 reactor were determined at the pneumatic irradiation station. To obtain these values, the “bare triple monitor” method was used with 198Au –97Zr – 95Zr. To evaluate its reproducibility, the temporal variation of these parameters was analyzed, with validation carried out through irradiation of reference materials of geological origin G-S-N (granite) and biological INCT-MPH-2 (mix of herbs). The results obtained for f and α show that such values ​​are reproducible and compatible with each other, according to the normal Gaussian distribution for up to 1 standard deviation of confidence. The results obtained for the elements detected in the samples agree with the recommended values, with relative errors (bias) less than 10%, except in the case of Mn in G-S-N (16.3%). These results indicate that it is possible to routinely use this method for LAN-IPEN researchers to analyze geological and biological samples.
Derechos de autor 2026 João Pedro Oliveira Flores, Renato Semmler, Marina F. Koskinas, Denise Simões Moreira, Ione Makiko Yamazaki, Paulo Sérgio Cardoso da Silva, Vera Akiko Maihara https://creativecommons.org/licenses/by/4.0
Evaluation of Public Exposure to Gamma Radiation in Cotonou, Southern Benin
The objective of this study is to assess public exposure to natural background gamma radiation in Cotonou, southern Benin, in West Africa. This is a cross-sectional study with both descriptive and analytical aims, conducted from July to December 2024. The methodology involved continuous, georeferenced measurement of the ambient gamma dose rate at a height of one meter (1 m) above ground level using a spectrometer. The study sites included city streets and selected markets, including Dantokpa, an open-air market, and eight indoor markets. A total of 341,991 data points were recorded along the streets and 16,202 were recorded within the markets. The ambient gamma dose equivalent rate along the streets ranged from 4.67 to 136.84 nSv·h– 1, with an average of 25.11 ± 12.72 nSv·h– 1. The highest average rate was observed in District 5, which hosts a cement manufacturing plant. The average dose rates were 23.71 ± 12.90 nSv·h– 1 at the Dantokpa market and 69.72 ± 21.96 nSv·h– 1 in the indoor markets. In the latter, the dose rates were higher than those recorded in their respective districts. The estimated external annual effective doses were 0.04 ± 0.02 mSv for streets, 0.10 ± 0.06 mSv for Dantokpa, and 0.30 ± 0.09 mSv for indoor markets. These values remain below the worldwide average of 0.87 mSv, as recognized by the United Nations Scientific Committee on the Effects of Atomic Radiation for public exposure to natural radiation of terrestrial and cosmic origin. Overall, ambient gamma radiation exposure in Cotonou is low, though higher in enclosed market environments. These values may serve as baseline references for future studies in Cotonou and other African cities.
Derechos de autor 2025 Dr Gilles David Houndetoungan, Dr Olatoundé Herbert Fachinan, Dr Mahougnon Boniface Zinsou, Dr Sonia Mahussi Gwladys Adjadohoun, Dr Gibril Abogbo, Dr Bonaventure Awede, Dr Martial Zoungrana, Dr Kuassi Marcellin Amoussou-Guenou https://creativecommons.org/licenses/by/4.0
ApplyApplying Deep Learning in gamma-spectroscopy for radionuclide identificationng Deep-learning in gamma-spectroscopy for radionuclide identification
This study presents the results of using a Deep Convolutional Neural Network model on gamma spectrum classification for radioactive waste management. The approach uses a modified version of the VGG-19 architecture, originally developed for image recognition with 1000 mutually exclusive classes. The modified VGG-19 architecture uses a gamma spectrum as input and classifies, on a nonexclusive basis, ten classes representing the ten most common radionuclides at IPEN's Radioactive Waste Management Department (Am-241, Ba-133, Cd-109, Co-57, Co-60, Cs-137, Eu-152, Mn-54, Na-22, Pb-210). Gamma spectra were generated using Monte Carlo simulations created with PENELOPE/PenEasy, simulating an HPGe detector with sources inside a steel drum filled with paper, representing the common content of the drums managed at IPEN's Radioactive Waste Management Department. The data set was augmented by mixing these simulated spectra into new spectra containing up to four radionuclides. Several distances from the detector to the drum (41 cm, 46 cm, 51 cm, and 56 cm) were used to create a representative data set. The data from 56 cm (originally 150 spectra after the argumentation process, 375 spectra) was used for validation. After 250 training epochs, the model achieved consistent performance in the training set, demonstrating the efficiency of the method.
Derechos de autor 2025 André Gomes Lamas Otero, Ademar José Potiens Júnior, Julio Takehiro Marumo https://creativecommons.org/licenses/by/4.0
Analysis of TG-43 dosimetric parameters for an Ir-192 HDR brachytherapy source using with the Geant4 toolkit
This study evaluated the dosimetric parameters of the Buchler G089 192Ir high-dose-rate brachytherapy source using the TG-43 formalism and Monte Carlo simulations with the Geant4 toolkit. The radial dose function and the anisotropy function were obtained for this source. For the radial dose function, a small discrepancy could be observed for larger radii. The dose rate constant (Λ) was also calculated in this study (1.114 cGy·h⁻¹·U⁻¹) showing a maximum relative difference of 0.45% when compared with reference values (1.119 and 1.115 cGy·h⁻¹·U⁻¹). The absorbed doses were obtained by positioning the source in the lowest voxel of the ICRP male phantom prostate and benchmarked against previous studies. For comparison criteria, the Amersham 6711-Oncoseed 125I source was also modeled and inserted in the same position of the prostate. Additionally, the dose enhancement effect due to the presence of gold nanoparticles (GNPs) was analyzed for the ¹⁹²Ir source, considering a homogeneous concentration of 30 mg·g⁻¹ in a tumor region simulated in the peripheral zone of the prostate. An approximately 18.5% increase in the absorbed dose was observed in this region, in agreement with results from previous studies.
Derechos de autor 2025 Alice Albuquerque, Dr. Luiz Antônio Ribeiro da Rosa, Dr. Denison S. Santos https://creativecommons.org/licenses/by/4.0
Development of a semi-analytical nodal methodology for one-dimensional eigenvalue problems based on multigroup neutron transport theory using the discrete ordinate formulation
A semi-analytical nodal methodology is described in this paper for obtaining the numerical solution of eigenvalue problems based on neutron transport theory, in slab geometry, with isotropic scattering, using the discrete ordinates and multigroup energy formulation. This new approach applies a quadratic polynomial approximation only to the fission term in the transport equation, which justifies the method being classified as semi-analytical. The numerical solution is obtained through two interconnected iterative processes: the outer iterative process, which uses the power method to obtain successive estimates for the fission source and the effective multiplication factor (<!-- [if gte msEquation 12]><m:oMath><m:sSub><m:sSubPr><m:ctrlPr></m:ctrlPr></m:sSubPr><m:e><m:r>k</m:r></m:e><m:sub><m:r>eff</m:r></m:sub></m:sSub></m:oMath><![endif]--> <span style="font-size: 11.0pt; line-height: 107%; font-family: 'Calibri',sans-serif; mso-ascii-theme-font: minor-latin; mso-fareast-font-family: 'Times New Roman'; mso-fareast-theme-font: minor-fareast; mso-hansi-theme-font: minor-latin; mso-bidi-font-family: 'Times New Roman'; mso-bidi-theme-font: minor-bidi; position: relative; top: 4.0pt; mso-text-raise: -4.0pt; mso-ansi-language: PT-BR; mso-fareast-language: PT-BR; mso-bidi-language: AR-SA;"> ), and the internal iterative process, which aims to obtain successive estimates of the angular neutron fluxes emerging from the homogeneous regions throughout the spatial domain. Once the eigenvalues are calculated, for each outer power iteration, the angular fluxes of neutrons emerging at the node faces and in the sweeping direction of the internal iterative process are estimated. These are incoming fluxes at the faces of adjacent nodes, which ensures the continuity of the numerical solution. Computational algorithms were implemented in MATLAB. Numerical results for a typical benchmark problem considering an ADS, c.f., Accelerator-Driven Subcritical Reactor, type model are provided to illustrate the accuracy of the converged numerical solutions in coarse-mesh calculations. Although the method is not free from spatial truncation error, the results for the benchmark problem were considered satisfactory with one node per region, and refining the spatial domain did not result in a high computational cost in terms of response time, with results approaching those of analytical solutions.
Derechos de autor 2025 Natália Rocha Pinheiro, Francisco Bruno Souza Oliveira, Hermes Alves Filho https://creativecommons.org/licenses/by/4.0
Electronic Brachytherapy: A Calibration Protocol in Terms of Absorbed Dose to Water"
New radiotherapy techniques have been innovative in recent decades with the aim of maximizing the dose to tumor tissue and reducing the dose to healthy tissue. One of the modalities that has gained prominence, using low-energy beams, is intraoperative radiotherapy (IORT), as it is a method based on high radiation doses (10–20 Gy) administered to the tumor bed immediately after surgical excision. IORT can be achieved through treatment with low-energy X-ray beams with some devices available on the market. However, such devices provide little dosimetric information and lack a calibration protocol. According to the recently updated recommendations of the TRS 398 standard (2024), for the use of low-energy beams, the ideal is to use a parallel plate ionization chamber calibrated in terms of absorbed dose in water. Based on TRS 398, this work established a calibration protocol for parallel plate dosimeters in terms of absorbed dose in water at the Center for Ionizing Radiation Metrology (CEMRI) of the Institute for Energy and Nuclear Research (IPEN).
Derechos de autor 2026 Fábio Dias, Orlando Rodrigues Jr, Maria da Penha Albuquerque Potiens https://creativecommons.org/licenses/by/4.0
Comparative Study of Thermal Neutron Flux from Gold Foil Activation.
This study presents a comparative analysis between Monte Carlo simulations (MCNP-5) and experimental measurements of thermal neutron fluence using gold foil activation at the TNF2 irradiation facility of the Neutron Metrology Laboratory (LNMRI/IRD). The MCNP-5 model was constructed to replicate the irradiator geometry and source configuration. Gold foils, both bare and cadmium-covered, were irradiated and analyzed via gamma spectrometry to determine the induced activity of 198Au. The results of the calculated nuclear reaction rates were compared to the measured activities through C/E (Calculated/Experimental) analysis. The findings show consistent agreement within experimental uncertainty, supporting the accuracy of the MCNP model and reinforcing the role of TNF2 in the national and international metrological infrastructure for neutron dosimetry. Future developments will include improvements in flux mapping and personal dosimetry applications.
Derechos de autor 2026 Watila Lins Silva, Max Ramos, Regio Santos Gomes, Achiles Astuto, Walsan Wagner Pereira https://creativecommons.org/licenses/by/4.0
Pathological Studies in Uteruses by X-ray Microtomography
X-ray computed microtomography (microCT) is an advanced technique for evaluating materials that uses the principle of X-ray attenuation to form high-resolution two- and three-dimensional images. This technique allows detailed visualization of the microstructures of biological samples through the digital combination of hundreds of cross-sections. As a non-destructive technique, microCT requires minimal sample preparation and does not cause damage to the analyzed material. This work aims to use microCT to obtain high-resolution images of the ex-vivo uterus, demonstrating the possibility of visualizing microstructures, detailing tissues and contributing to the anatomical and pathological study of these organs. The research also highlights the relevance and usefulness of microCT as a modern and effective technique for the non-destructive analysis of biological samples, emphasizing its potential in several areas of science and medicine. In addition, it seeks to validate microCT as an essential tool for medical research, providing a deeper understanding of the internal structures of organs and their possible pathologies.
Derechos de autor 2026 Larissa M. Gonçalves, Olga M. O. Araujo, Alessandra S. Machado, Pedro Castro, Ricardo T. Lopes https://creativecommons.org/licenses/by/4.0
Development of Spheroid in Co-Culture of Prostate Tumor with Human Fibroblast, using the Hanging Drop Technique with Plate Inversion for Analysis of GammaCell220 Irradiation in Co-60
The development of tumor spheroids in co-culture with human fibroblasts represents an innovative approach to modeling the prostate cancer microenvironment and assessing radiation effects. In this study, we employed the "hanging drop" technique in conjunction with plate inversion to generate three-dimensional spheroids composed of prostate tumor cells (LNCAP cell line) co-cultivated with human fibroblasts. This approach aims to create a more representative in vivo-like tumor environment, facilitating a detailed analysis of the interactions between tumor cells and fibroblasts in 3D conditions. The formed spheroids were exposed to gamma radiation using a GammaCell 220 irradiator with Co-60, with the goal of investigating the effects of radiation on both fibroblastic and tumor cells. Gamma radiation is known to induce cell death, and this study examines how such damage impacts cellular morphology within the spheroid microenvironment.
Derechos de autor 2026 Thais Monteiro, Alex Alves Rodrigues, Giovana Dias da Silva, Esther Carolina dos Santos, Patricia Lima Falcão, Suleyna Ribeiro Prudente, Mayelle Maria Paz, Daniel Perez Vieira https://creativecommons.org/licenses/by/4.0
Estudio retrospectivo de la exposición a las radiaciones ionizantes durante procedimientos de cardiología intervencionista realizados en el Centro Cardiovascular Universitario del Uruguay
El número de procedimientos de cardiología intervencionista ha aumentado rápidamente durante las últimas décadas. Los procedimientos de fluoroscopía con rayos X, como la angiografía coronaria y la angioplastia coronaria transluminal percutánea, se consideran la mayor fuente de exposición médica ocupacional, ya sea para pacientes u operadores, causando efectos nocivos para la salud. En este sentido, se han desarrollado diversas modificaciones en los procedimientos clásicos de cardiología intervencionista así como la incorporación de protocolos de protección radiológica para reducir la exposición a la radiación. Para conocer adecuadamente el éxito en la aplicación de estos cambios se deben establecer los valores de referencia de exposición a la radiación para diferentes procedimientos de cardiología intervencionista. Para ello se realizó un estudio retrospectivo, transversal y descriptivo en el Centro Cardiovascular Universitario de la Facultad de Medicina (Universidad de la República) del Uruguay entre 2018 y 2020, con el objetivo de conocer la frecuencia de procedimientos realizados, así como el promedio de la dosis de radiación administrada, el tiempo de fluoroscopia y el producto Kerma-rea para cada procedimiento intervencionista. El procedimiento de angioplastia urgente fue el procedimiento intervencionista realizado con más frecuencia y produjo el mayor nivel de exposición de los trabajadores y pacientes a la radiación ocupacional. Se establecieron por primera vez en Uruguay niveles de referencia para los tres procedimientos de cardiología intervencionista más frecuentes utilizando el tercer cuartil de los parámetros de exposición a la radiación empleados (Dosis total administrada, producto Kerma-área y tiempo de fluoroscopia). Los valores de referencia obtenidos coincidieron con los encontrados a nivel internacional.
Derechos de autor 2026 Rafael Mila, Fredy Hernandez, Jaime J. Cordon, Ariel Duran, Wilner Martínez-López https://creativecommons.org/licenses/by/4.0
Study for the Development of a Biosensor Aimed at the Interaction-Response of Chemical War Agents and Ionizing Radiation
It has long been known that the nuclear sector is a potential branch capable of solving major obstacles relevant to modern society with regard to energy demands. The technology in this sphere is associated with various possibilities, including areas that require multidisciplinary expertise for their respective advancements, such as medical sciences, security and defense, national autonomy and sovereignty, energy generation, food technology, among others. With the development of nanostructured technologies, highly sensitive, accessible, and easy to handle, it is possible to introduce new alternatives to reduce the “gap” between these possibilities within the sector, making the nuclear area more visible to new researchers due to the potential for new research to be developed. With the prospect of innovation for the sector and with increasing technological input, a special look at instrumental and measurement issues is necessary, since it is also necessary to ensure the quality of nuclear technology for the development of any system focused on this theme. This research presents a combination of different areas, highlighting the multidisciplinarity of construction, aiming to obtain the necessary support for the creation of a device capable of interacting with systems that represent chemical and radiological-nuclear threats. As it is a biosensor, it presents a biological interface sensitive to chemical warfare agents (organophosphates), neurotoxins and undergoes a process analogous to radiolysis, it is the means by which it is possible to associate electronics to the system, being capable of transducing information from one form of energy to another, making it possible to quantify and obtain relevant and proportional information about the exposure of this system created. For the in silico study carried out, the energy fluctuations for both the chemical simulations and the MCNP simulations were guiding the verification process, since the lower the energy value, the stronger the chemical interaction between ligands and enzymes.
Derechos de autor 2025 João Nilton da Conceição Bandeira, Fabiane Modenese Garbim, Joyce Sobreiro Francisco Diz De Almeida, Álvaro José Boareto Mendes, Fernando Manuel Araújo Moreira https://creativecommons.org/licenses/by/4.0
Evaluation of the antioxidant, cytotoxic and radioprotective potencial of the lectin WSMoL from Moringa oleífera Lam. seeds
WSMoL (water-soluble lectin from the seeds of Moringa oleifera Lam.) is widely known for its biological properties, especially for its inflammatory, immunomodulatory and antitumor activity and is a promising candidate for a radioprotector of natural origin. Aim of the study: This study aimed to evaluate the antioxidant and cytotoxic potential and the radioprotective effect of WSMoL in human lymphocyte culture (PBMC). The concentrations analyzed were 850, 425, 212.5, 106.25 and 53.12µg/mL. Materials and methods: Antioxidant activity was tested using the DPPH and ABTS assays. Cell viability and cytotoxicity were assessed using the MTT assay on PBMC lymphocytes. Radioprotection was verified by the Alkaline Comet and Micronucleus with Blockage of Cell Cytokinesis assays after exposure to Cobalt-60 gamma radiation. Results: In the DPPH test, WSMoL was unable to capture the radical. In the ABTS test, the inhibition index (I%) was ≤10% and the IC50 was 71.42 g/L. The MTT test showed that the lectin was not cytotoxic and cell viability was over 79%, with a maximum (≤125%) at a concentration of 53.12 µg/mL. In the Alkaline Comet test, the Damage Index (DI) observed was high at concentrations of 850 and 53.12 µg/mL (≥170 ± 30). The Damage Frequency (y) observed through the Micronucleus assay was 0.260 for the two concentrations analyzed, similar to the y of the irradiated control group. Conclusion: WSMoL did not show significant antioxidant activity in the DPPH and ABTS tests. The lectin did not show a cytotoxic profile, and its use at a concentration of 53.12µg/mL is recommended. WSMoL showed no radioprotective capacity after exposure to gamma radiation at a dose of 2.5Gy.
Derechos de autor 2025 Osana Diniz Ferreira, Andreza Lima Lourenço da Silva, Karine Lafaiete De Carvalho, Thaynara Maria Arantes, Vinícius Henrique Teixeira Morais, Dewson Rocha Dewson Rocha Pereira, Thiago Henrique Napoleão, Mércia Liane de Oliveira, Ana Maria Mendonça de Albuquerque Melo https://creativecommons.org/licenses/by/4.0
Tissue Reactions (Deterministic Effects) in Diagnostic and Interventional Radiology: An Integrative Review of Recent Literature
Ninety-eight percent of the global average individual dose delivered by artificial sources of ionizing radiation results from their use in medical applications, especially for diagnostic and interventional purposes. Although the benefits of radiation in medicine are widely recognized, exposure to this agent can cause harmful effects on the health of exposed individuals. Radiation applications for diagnostic purposes are generally associated with low doses, but interventional procedures may involve much higher doses. In the 2000s and 2010s, several publications described tissue reactions in patients and professionals exposed during interventional radiological procedures. This work aimed to review the literature on the most recent reports (last decade) on the occurrence of tissue reactions after diagnostic or interventional radiological procedures. The PubMed search tool was used to search and select publications on the topic. Although 826 articles were initially selected, only 5 presented relevant content for this review. The low number of articles in the final selection may be a result of the methodology we used or an actual reduction in the number of individuals presenting these effects in more recent years, due to the growing concerns about radiological protection in these practices. Among the articles analyzed, there were reports of skin lesions, as well as thinning or hair loss in patients exposed to doses (cumulative air kerma at the reference point) above 3.5 Gy. However, these reactions are rare and do not appear in most patients, even among those who received higher doses. An increased frequency of lens opacities (cataracts) has also been reported in occupationally exposed professionals. An adequate assessment of the occurrence of these effects is essential to try to understand their causes and minimize the frequency or consequences of their occurrence. Carrying out research like this can help with this task.
Derechos de autor 2025 Laisa Neves, Lucía Canevaro Lucía Viviana Canevaro, Ana Dovales Ana Cristina Murta Dovales https://creativecommons.org/licenses/by/4.0
Human biomonitoring in residents of a NORM area using the comet assay, Pernambuco-Brazil
Geological research has found areas of uraniferous phosphorite in northeastern Brazil. This region is located along the coast of the states of Paraíba and Pernambuco, Brazil. Its distribution in Pernambuco is located in the Metropolitan Region of Recife/Região Metropolitana do Recife (RMR), covering the municipalities of Abreu e Lima and Olinda. Studies have been carried out in these municipalities, verifying the presence of Naturally Occurring Radioactive Material (NORM) in different matrices: soil, groundwater, air and fruit. Given these facts, the need arose to carry out human biomonitoring (HBM) in residents of these municipalities. Therefore, the aim of this study was to assess possible DNA damage in the residents of Olinda and Abreu e Lima by means of the comet assay using lymphocytes. The results showed high levels 3 and 4 damage to the DNA of the volunteers in the sample group who are under the influence of NORM, demonstrating a statistically significant difference in the damage index when compared to the control group. It is suggested that the genotoxic results found may be related to the NORM present in the municipality of Abreu e Lima, thus influencing the health of its residents. The research is relevant because it is a pioneer in the generation of scientific knowledge in the area of the study of uraniferous phosphorite using HBM.
Derechos de autor 2025 Vinícius Henrique Teixeira Morais, Dewson Rocha Pereira, João Emanuel Firmo Pinto, Osana Diniz Ferreira, Ana Maria Mendonça de Albuquerque Melo https://creativecommons.org/licenses/by/4.0
Evaluaciones de los posibles efectos mutagénicos y genotóxicos de los 2-ACBs: subproductos generados a partir de alimentos irradiados
Este estudio investiga los posibles efectos mutagénicos y genotóxicos de los subproductos 2-Alquilciclobutanonas (2-ACBs), formados en alimentos irradiados. Las 2-ACBs son compuestos derivados de la irradiación de alimentos que contienen grasa, con reconocido potencial genotóxico. La investigación se centró en los compuestos 2-dodecilciclobutanona (2-dDCB) y 2-tetradecilciclobutanona (2-tDCB), evaluando su mutagenicidad mediante el ensayo de micronúcleos en líneas celulares hepáticas (HepG2, BRL3A y HTC) y genotoxicidad a través del ensayo de Ames utilizando cinco cepas bacterianas (TA-98, TA-100, TA-1535, TA-1537 y WP2uvrA). Los resultados del ensayo de Ames indicaron que 2-dDCB y 2-tDCB no aumentaron significativamente las tasas de reversión mutagénica, mientras que los ensayos de micronúcleos mostraron ausencia de daños genotóxicos en las líneas celulares analizadas. Se concluye que, en las concentraciones evaluadas, los compuestos 2-dDCB y 2-tDCB no presentan potencial mutagénico ni genotóxico, lo que corrobora la seguridad de los alimentos irradiados. No obstante, se recomienda la realización de investigaciones adicionales para evaluar los efectos a largo plazo y bajo diferentes condiciones de irradiación
Derechos de autor 2025 Angélica Bueno Barbezan, Ana Carolina de Araújo Bispo, Bruno Melo Mendes, Daniel Perez Vieira, Luma Ramirez de Carvalho, Glaucia Maria Machado-Santelli, Anna Lúcia Casaas Haasis Villavicencio https://creativecommons.org/licenses/by/4.0