EDUARDO SANTANA DE MOURA

EDUARDO SANTANA DE MOURA

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Production of iodine-125 in nuclear reactors
2011 - ZEITUNI, CARLOS A.; ROSTELATO, MARIA E.C.M.; JAE-SON, KWANG; LEE, JUN S.; COSTA, OSVALDO L.; MOURA, JOÃO A.; FEHER, ANSELMO; MOURA, EDUARDO S.; SOUZA, CARLA D.; MATTOS, FABIO R.; PELEIAS JUNIOR, FERNANDO S.; KARAM JUNIOR, DIB
Cancer is one of the worst illnesses in the world and one of the major causes of death in Brazil [1,2]. For this reason, the Nuclear Energy National Commission (CNEN) started a project to produce some medical radioisotopes to treat cancer. One of the main products is the iodine-125 seeds [3]. This iodine seed can be used to treat several kinds of cancer: prostate, lung, eye, brain. As Brazil will construct a new reactor to produce radioisotopes, it is necessary define how the iodine-125 production will carry out [4,5]. The main reaction of this production is the irradiation of the enriched xenon-124 in gaseous form. Xe-124 changed to Iodine-125 by neutron capture following in two decays: Xe-124 (n, y) —• Xe-125m (57s) —• I- 125 or Xe-124 (n, y) —• Xe-125 (19.9 h) —• 1-125. However the production in reactors is the most common technique used, there is one disadvantage to use it: the production of iodine- 126 after several hours of irradiation. Iodine-126 has a half life of 13.1 days and it has some usefulness emitters for medical uses. Iodine-126 is considered a contamination [6]. For all these reasons, the IPEN/CNEN-SP research group decided for two techniques of production: in batch or continuous system. The production in batch consists in a sealed capsule that is placed in the reactor core for around 64 hours. In this type of production, some iodine-126 is produced and a certain quantity of Xe-124 is not activated. Normally, it needs to wait around 5 to 7 iodine-126 half-lives to guarantee the decrease of the activity of the contamination. This time will make Iodine-125 with only 50% till 34% of the initial production. The second technique is the continuous production using a cryogenic system. This technique consists in two capsules: one inside the reactor core and the second one out of the neutron flux. These two capsules will be linked with two cryogenic pumps to guarantee that all iodine-125 produced in the core will be take off the reactor core. The great disadvantage of this technique is the using of two positions in the core of the reactor. Brazil will have only one radioisotope reactor producing. And like there is a huge quantity of materials to be produced, it is not a guarantee the position in the reactor for this production. Besides of that the seeds production in Brazil is only 3000 per month, which demands around 3.5 Ci per month. The batch production produces a low quantity per reactor cycle of iodine-125, but this low quantity can be more than that [2,3].
Preliminary proposal for radioactive liquid waste management in a brachytherapy sources production laboratory
2011 - SOUZA, CARLA D.; VICENTE, ROBERTO; ROSTELATO, MARIA E.C.M.; ZEITUNI, CARLOS A.; MOURA, JOÃO A.; MOURA, EDUARDO S.; MATTOS, FABIO R.; FEHER, ANSELMO; COSTA, OSVALDO L. da; VIANNA, ESTANISLAU B.; CARVALHO, LAERCIO de; KARAN JUNIOR, DIB
Malignant tumors are responsible for a high death rate in the entire world population (1). Prostate cancer is the third most common among men, after skin and lung. The treatment using permanent Iodine-125 seed are too costly, preventing the use in large scale (1) (2). A multidisciplinary team was formed to develop a source of Iodine-125 and assemble a national facility for local production. For the production correct implementation, a plan for radiological protection that has the management of radioactive waste fully specified are necessary. This work has developed an initial liquid waste management proposal. The most important Iodine-125 liquid waste is generated in the first phase of the process, radioactive material fixation. The initial proposal is that the waste is deposited in a 20 L container (2 years to fill). The final activity of this container is 4.93 x 1011 Bq. According to the discharge limits presented in the brazilian's regulation CNEN - NE - 605 - Management of radioactive wastes in radioactive facilities (3) this waste could safely be release to the environment in 3.97 years. In the other hand,if a minimization waste policy will be implemented, the production could becomes more efficient and cheaper. Waste storage at 25 L containers and changing some production parameters results in 3 years waste to be eliminated in 3.94 years. This new plan will optimize the materials used and diminished the waste generation facilitating the management, contributing to a cheaper product.
Iridium-192 seed development for ophthalmic cancer treatment
2011 - ROSTELATO, M.E.C.M.; MATTOS, F.R.; ZEITUNI, C.A.; SOUZA, C.D.; MOURA, J.A.; MOURA, E.S.; FEHER, A.; COSTA, O.L.; PELEIAS JUNIOR, F.S.; MARQUES, J.R.O.; BELFORT NETO, R.
Considered a public health problem in Brazil, cancer is the second leading cause of mortality by disease, representing 13.2% of all deaths in the country [1]. Ophthalmic brachytherapy involves inserting an acrylic plate with radioactive material in the eyes of a patient for treatment of ocular tumors. This work is a partnership between Escola Paulista de Medicina - UNIFESP and the Instituto de Pesquisas Energéticas e Nucleares - IPEN for development and implementation of a cheaper therapeutic treatment for ophthalmic cancer with a iridium-192 source, to attend a greater number of patients. Iridium-192 is produced in nuclear reactor. It has a half-life of 74.2 days and decays by beta emission with average energy of 370 keV.[2,3]. The seed will be a platinum-iridium alloy core (80/20), encapsulated in a titanium tube [4]. This project will be divided into the following steps: characterization of materials by FRX (X-ray fluorescence) e EDS (Energy Dispersive Spectroscopy); iridium irradiation in the nuclear reactor IEA-R1; sealing of iridium-192 seed; leakage tests of iridium-192 source in accordance with standard ISO-9978 (radiation protection- Sealed radioactive sources- Leakage test methods) [5]; metallographic tests and measure the activity of the source. The evaluation for use in the ophthalmic treatment of cancer will be made later.
Improvements in the quality control of iridium-192 wire used in brachytherapy
2011 - COSTA, OSVALDO L.; ZEITUNI, CARLOS A.; ROSTELATO, MARIA E.C.M.; MOURA, JOÃO A.; FEHER, ANSELMO; MOURA, EDUARDO S.; SOUZA, CARLA D.; SOMESSARI, SAMIR L.
Brachytherapy is a method used in the treatment of cancerous tumors by ionizing radiation produced by sources introduced into the tumor area, this method seeks a more direct attack to the tumor, thereby maximizing the radiation dose to diseased tissue while minimizing the dose to healthy tissues (1). One of the radionuclides used in brachytherapy is iridium-192. The Radiation Technology Center (CTR) of the Nuclear and Energy Research Institute (IPEN) has produced commercially, since 1998, iridium-192 wires used in low dose rate (LDR) brachytherapy (2). To produce this radionuclide, firstly a iridium-platinum wire is irradiated in the nuclear reactor IEA-R1 for 30 hours with a neutron flux of 5 x 1013 ncm-2s-1, the wire is left to decay by 30 days to remove the main contaminants and then goes through a quality control before being sent to the hospital. In this quality control is checked the radiation homogeneity along each centimeter of the wire (3). To implement this procedure is used a device consisting of an ionization chamber surrounded by a lead shield with a small 1 cm wide slit, linked to the ionization chamber is a voltage source and a Keithley 617 electrometer, 2 minutes is the range used to measure the charge by the electrometer. The iridium wire is considered in accordance when there is no variation greater than 5% between the average measures and the maximum and minimum values. However, due to design features of the measurement system, the wire may appear to the detector through the slit in larger sizes than the ideal, improperly influencing the final quality control. This paper calculates the difference in size of these variations in profile and their influence on the final count, it compares the actual values obtained and describes the improvements made in quality control procedures that provided more accurate measurement data, analyzes the results and suggests changes in devices aimed at further improving the quality control of iridium-192 wires produced at IPEN and used in hospitals in Brazil.
Waste management protocols for Iridium-192 sources production laboratory used in cancer treatment
2016 - ROSTELATO, MARIA E.C.M.; SOUZA, CARLA D. de; SOUZA, DAIANE C.B. de; ZEITUNI, CARLOS A.; TIEZZI, RODRIGO; COSTA, OSVALDO L. da; RODRIGUES, BRUNA T.; MOURA, JOÃO A.; FEHER, ANSELMO; SORGATTI, ANDERSON; MOURA, EDUARDO S. de; MARQUES, JOSE R. de O.; SANTOS, RAFAEL M. dos; KARAM JUNIOR, DIB
Introduction: Brachytherapy is a form of treatment that uses radioactive seeds placed in contact or inside the region to be treated, maximizing the radiation dose inside the targeted areas. Iridium-192 is being used in brachytherapy since 1955. It presents emission energy in the “therapy region” (370keV) and is easily produced in a nuclear reactor (191Ir (n, γ) → 192Ir). Wires are an iridium-platinum alloy with 0.36 mm diameter and they can be cut in any needed length. They can be used in several types of cancer. The linear activity is between 1 mCi/cm (37 MBq/cm) and 4 mCi/cm (148 MBq/cm) with variations of 10% in 50 cm maximum. This activity values classified the treatment and low dose rate (0,4 à 2 Gy/h). The propose of this work is to present a waste management system in a cancer treatment radioactive sources production laboratory. Methodology and Results: The solid waste is previously characterized in the analysis phase. The contaminants are already known and they are insignificant due to their fast half- life. The iridium-192 half-life is 74.2 days, classified as very short half-life waste. The waste activity is adds to 8mCi (2.96x108 Bq) per wire. According to the CNEN-NN 6.08 standard, that presents the discharge levels, the limit is 1 kBq.kg-1 (2.7x10-5 mCi.kg-1). The radioactive waste generated during the I192 wires production has a weakly activity of 9.7 GBq.g-1. According to the standards, this activity is too high to be discarded into the environment. The waste must be managed following the ALARA principal using the R&R (retain e retard) system, that means, temporary storage and posterior discharge. Since every 4 months, maintenance is performed inside the hot cell used for production, the waste must be removed. Using the equation: 𝐴 = 𝐿 λ (1 − 𝑒−λt), the total calculated activity is 1.68 x 1016 Bq and 4.8 g mass at the end of each 4 months period. This amount is stored inside a shielding device that has 212.37 cm3 volume. The waste will take 9.8 years (calculated by 𝐴 = 𝐴0(𝑒−λt)) to decay to the discharge levels. To store 30 devices during 10 years, a space with 6,370 cm3 is necessary. The laboratory has enough space for this storage. Thus, the radioactive waste management can be performed through the R&R (retain and retard) system safely.
Waste management protocols for iridium-192 sources production laboratory used in cancer treatment in Brazil
2017 - ROSTELATO, M.E.C.M.; SOUZA, D.C.B.; SOUZA, C.D.; ZEITUNI, C.A.; VICENTE, R.; COSTA, O.L.; RODRIGUES, B.T.; MOURA, J.A.; FEHER, A.; MOURA, E.S.; MARQUES, J.R.O.; CARVALHO, V.S.; NOGUEIRA, B.R.
Objective: The iridium-192 wired sources production results in radioactive waste that needs to follow the guidelines. The aim of this study is to do a radioactive waste management of wastes from iridium-192 sources production laboratory used in cancer treatment in Brazil. Methods: The wire is acquired in an alloy form with 80% platinum and 20% iridium encapsulated with 100%. Electronic microscopy, X-ray fluorescence, and posterior iridium neutron activation (to determine contaminants) are performed to ensure quality. A 50-cm twisted wire is placed in an aluminum tube. The tube is sealed and place inside the reactor irradiator system and is left for decay during 30 hours to wait for the others undesired activation products to decay. The wire is prepared for treatment with 48 cm length with 192 mCi maximum activity. All the equipment use inside the hot cell must be calibrated every four months. All the waste must be removed from the hot cell. Results: The solid waste is previously characterized in the analysis phase. The contaminants are already known and they are insignificant due to their fast half-life. The iridium-192 half-life is 74.2 days, classified as very short half-life waste. The reminiscent activity is 8mCi. Conclusion: The radioactive waste generated during the I192 wires production is solid, was a short half-life and a weakly activity of 9.7 GBq.g-1. According to the standards, this activity is too high to be discarded into the environment (limit 10 Bq.g-1). The waste must be managed by the R&R (retain e retard) system.
Brazil radioactive sources production for cancer treatment
2016 - ROSTELATO, MARIA E.; SOUZA, CARLA D.; ZEITUNI, CARLOS A.; MOURA, JOAO A.; MARQUES, JOSE R.O.; COSTA, OSVALDO L.; FEHER, ANSELMO; RODRIGUES, BRUNA T.; SOUZA, DAIANE C.B. de; PELEIAS JUNIOR, FERNANDO S.; SORGATTI, ANDERSON; MOSCA, RODRIGO; MOURA, EDUARDO S. de; ABREU, RODRIGO T.; SOUZA, RAQUEL V. DE; NOGUEIRA, BEATRIZ R.
The modality, known as brachytherapy, was performed in Brazil by only a hand full of hospitals at an extremely high cost. For producing new sources, five major areas must be considered: 1) source production: nuclear activation and/or radiochemical reaction; 2) welding; 3) Quality control: leakage tests; 4) Dosimetry and metrology; 5) Operational procedures; 6) validation studies. To perform all steps, a multidisciplinary team works together to overcome difficulties. - Iridium-192 pellets: In Brazil there are 140 machines with pellets that replacement every 5 years. Our new production line has assembly, welding and quality control hot cells. - Iridium-192 wires: Produced since 1999. The wire is activated at IPENs IEA-R1 reactor for 30 hours with 5x1013 n/cm-2.s-1 neutron flux resulting in 192 mCi maximum activity. - Iridium-192 seed: New seed for ophthalmic cancer treatment. The irradiation device presented 90% activity homogeneity. We are still testing in-vivo. - Iodine-125 seeds: Largely used in low dose brachytherapy. I-125 binding yield achieved with our new reaction was 80%; Laser welding presented 70% efficiency. Approved in all leakage tests. - Other ongoing projects: Veterinary brachytherapy, Waste management, Radionecrosis healing with laser, calibrations sources production, linear accelerator calculations for hospitals, sources with polymeric matrix Our Iodine-125 seeds will be available in 2018. All other projects are advancing. We will continue to develop new products hoping to help the Brazilian population fight against cancer. For producing new sources, five major areas must be considered: 1) source production: nuclear activation and/or radiochemical reaction; 2) welding; 3) Quality control:eakage tests; 4) Dosimetry and metrology; 5) Operational procedures; 6) validation studies. To perform all steps, a multidisciplinary team works together to overcome difficulties
Estudo, desenvolvimento e produção de fontes radioativas para radioterapia
2013 - ROSTELATO, MARIA E.C.M.; ZEITUNI, CARLOS A.; MOURA, JOAO A.; FEHER, ANSELMO; COSTA, OSVALDO L. da; MOURA, EDUARDO S. de; SOUZA, CARLA D. de; KARAM JUNIOR, DIB
Desde 1997, o IPEN-CNEN/SP por meio do seu “Laboratório de Produção Fontes para Radioterapia - LPFR”, produz fontes radioativas de Irídio-192, na forma de fi os, e fornece aos hospitais para utilização em radioterapia de baixa taxa de dose (LDR). Está em fase de conclusão, a montagem de uma instalação para a produção de fontes radioativas de Iodo-125, na forma de sementes, para uso em tratamento de câncer de próstata, oftálmico e cerebral. Essa instalação consiste de três glove-box (uma caixa estanque). A primeira, semi-automatizada, é a reação do iodo radioativo com o núcleo de prata que forma a semente. É a parte do processo que apresenta maior risco, tendo diversos sistemas redundantes de segurança como duplo fi ltro, depressão de ar e proteção física. A segunda é a solda da cápsula de titânio que envolve esse núcleo. Essa parte é inteiramente automatizada e o controle visual da qualidade da solda é feito pelo operador através de um sistema de câmaras. A terceira fase é o controle de qualidade, totalmente automatizado, que garante a estanqueidade das sementes prontas de acordo com a norma ISO 9978 - “Sealed Radioactive Sources-Leak Test Methods”. Como fase extra a dosimetria da semente está em desenvolvimento. Ela engloba o estudo de diversos parâmetros que auxiliam no cálculo da dose exata que o paciente recebeu ao utilizar esse tratamento. O grupo espera a conclusão para 2014. Atualmente encontra-se em desenvolvimento e implementação um laboratório para produção de fontes de Irídio-192, na forma de “pellets”, para utilização em radioterapia de alta taxa de dose (HDR). Estas fontes são importadas acarretando altos custos para a sociedade. Estas fontes são usadas para tratar vários tipos de câncer. Por exemplo: colo de útero, mama, pulmão e outros. A produção local de fontes radioativas para radioterapia reduzirá sensivelmente seus custos, permitindo um aumento do número de pacientes tratados no país. A proteção implementada no caso do Irídio-192 é maior quando comparada com o iodo-125. O primeiro isótopo apresenta energia de emissão entre 0,137 a 0,65 MeV enquanto o segundo 0,03MeV. Por essa razão o irídio será manipulado em hot cell (célula quente) que são enormes estruturas totalmente revestidas de chumbo pesando aproximadamente 25 toneladas. O operador usará um telemanipulador e o sistema do ar será totalmente selado. O vidro para visualização contém chumbo na formulação. Como resultado o operador leva praticamente nenhuma dose de radiação. O grupo espera a conclusão do novo prédio em 2018.
Study and evaluation of aluminium capsules to irradiation of gaseous samples in nuclear rector
2015 - COSTA, OSVALDO L. da; FEHER, ANSELMO; MOURA, CARLA D.; TIEZZI, RODRIGO; SOUZA, DAIANE C.B. de; MOURA, EDUARDO S.; OLIVEIRA, HENRIQUE B.; ZEITUNI, CARLOS A.; ROSTELATO, MARIA E.C.M.
Desenvolvimento da metodologia para sintese do poli-)acido latico-co-acido glicolico) para utilização na produção de fontes radioativas
2015 - PELEIAS JUNIOR, FERNANDO dos S.; ZEITUNI, CARLOS A.; ROSTELATO, MARIA E.C.M.; FECHINE, GUILHERMINO J.M.; SOUZA, CARLA D. de; MATTOS, FABIO R. de; MOURA, EDUARDO S. de; MOURA, JOAO A.; BENEGA, MARCOS A.G.; FEHER, ANSELMO; COSTA, OSVALDO L. da; RODRIGUES, BRUNA T.