ANSELMO FEHER

ANSELMO FEHER

(Fonte: Lattes)

Resumo

Graduado em Tecnologia Mecânica com ênfase em soldagem pela Faculdade de Tecnologia de São Paulo (1992), possui mestrado em Tecnologia Nuclear pela Universidade de São Paulo (2006) e doutorado em Tecnologia Nuclear pela Universidade de São Paulo (2014). Atualmente é Servidor Público Federal da Comissão Nacional de Energia Nuclear, órgão vinculado ao Ministério da Ciência, Tecnologia e Inovação. Tem experiência nas áreas de Engenharia Mecânica e Aplicações Nucleares, atuando principalmente em desenvolvimento e manutenção de sistemas de alto vácuo, ensaios de detecção de vazamentos utilizando espectrômetros de massa para gás hélio, produção de fontes radioativas seladas, soldagem por arco plasma, soldagem a laser, braquiterapia, sementes de iodo-125 e fontes de irídio-192 para tratamento de câncer. (Texto extraído do Currículo Lattes em 28 mar. 2023)

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Nationalization of brachytherapy radioactive sources in Brazil and the importance of IAEA cooperation
2023 - ROSTELATO, MARIA E.C.M.; FEHER, ANSELMO; ZEITUNI, CARLOS A.; ROSERO, WILMMER A.A.; SOUZA, CARLA D. de; MOURA, JOÃO A.
Brazil has a cancer incidence of about 625,000 cases a year. It is a public health problem, demanding constant efforts to deliver for patients the most efficient treatment modalities, improving their life expectancy and quality. Brachytherapy is a type of Radiotherapy where the radioactive source is placed close to or inside the tumor. The main advantage of the technique is to deliver the maximum dose in the target, saving healthy tissues. In Brazil, Our group had the objective of producing sources nationally, diminishing treatment costs, enabling the treatment to more patients. Some of our projects are developed in collaboration with the International Atomic Energy Agency-IAEA by technical cooperation projects. The IAEA participation is very important to provide technological transfer through scientific visits, expert missions, and contacts with more advanced centers. The financial support is also important, allowing us to buy the necessary equipment to make these cancer treatment sources production feasible in Brazil. Our team has received training through fellowships. We received some experts and organized several workshops to propagate the Brachytherapy technique at national and Latin American level. 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. Our major projects are: Iridium-192 pellets: In Brazil there are 150 afterloading machines with pellets that replacement every 4 months (about 450 Iridium-192 sources a year). Our new production line, with the support of IAEA, is in progress, with the hot-cell being installed in a brand-new facility. Iridium-192 wires: In production since 1997, also supported by IAEA. The wire is activated at IPEN’s IEA-R1 reactor for 30 hours with 5x1013 n/cm-2.s-1 neutron flux resulting in 7.1 GBq (192 mCi) maximum activity. Iridium-192 seed: New seed for ophthalmic cancer treatment. The core presented 90% activity homogeneity. We are making the experimental dosimetry and Monte Carlo simulation. Iodine-125 seeds: Largely used in low dose brachytherapy. I-125 binding yield achieved with our new reaction was 90%; Laser welding presented 70% efficiency. Approved in all leakage tests. Our Iodine-125 seeds laboratory production is 90% ready. Other ongoing projects: polymeric Phosphorus-32 source for spinal cancer treatment, Gold-198 nanoparticles for prostate, breast, and liver cancer treatment, Iodine-125 seed as markers for non-palpable cancers, and dosimetry calculations for all new sources. All the projects are advancing, despite national funding difficulties. Withing those, several mSc, Phd, and Post-doc are getting their degrees. We will continue to develop new products hoping to help the Brazilian population fight against cancer. The support of IAEA has proven to be of the utmost importance for these projects not only in direct funding, but in providing knowledge to our team, the possibility to share information with the scientific community, and to form the next generation of scientists.
Challenges in iodine-125 sources production for cancer treatment
2023 - FEHER, ANSELMO; BAPTISTA, TATYANA S.; ZEITUNI, CARLOS A.; ROSTELATO, MARIA E.C.M.; MOURA, JOÃO A.
There is a great challenge the implantation on assurance quality system in the brachytherapy sources production. It involves tofulfill the Good Manufacturing Practices (GMPs) requirements, involving the process validation and of all supporting activities such as cleaning and sanitization. The purpose of this work was to execute a process validation in the iodine-125 seeds production on Radiation Technology Center located at IPEN- Brazil. Besides this, the sanitization was to evaluate the effectiveness of different surface cleaning products, determining the best to reduce radiological contamination to acceptable levels during the sources production, according to legislation. The fabrication process was performed three times for evaluation. The parameters evaluated in this study were: the source welding efficiency and the leakage tests results (immersion test). The welding efficiency doesn’t have an established parameter, since is visually evaluated by the operator, and the leakage detection has to be under 5 nCi / 185 Bq, accordingly with the ISO 9978. In the relation of sanitization, it was established a cleaning program for three production lots of iodine 125 seeds using three types of sanitizers: Lot 1 with extran 1/1 (v/v), Lot 2 with hydrogen peroxide 6% and Lot 3 with sodium hydroxide 1M. Each lots contained seven iodine 125 seeds and was immersed in the sanitizer for 1 hour and then two washes with distilled water. An activity detected in each lots does not exceed 0,2 kBq (˭5nCi). The observed values on process validation were: 75% welding efficiency and 32% leakage detection. Although established values for the global efficiency aren’t available in the literature, the results showed high consistency and acceptable percentages, especially when other similar manufacturing processes are used in comparison (average 85-70% found in the literature for other similar metallic structures). According to results of sanitization, the best choice for remove de surface contamination was peroxide hydrogen. Further testing should ensure the sanitizer's choice is based not only on the removal of surface contamination, but also this sanitizer does not leave residues requiring further rinsing with distilled water. Those values will be important data when drafting the validation document and to follow the Good Manufacturing Practices (GMPs).
Electron beam processing to improve biodegradable polymers and for industrial wastewater treatment and recycling
2022 - CALVO, W.A.P.; MUNHOZ, P.M.; SOMESSARI, S.L.; DUARTE, C.L.; SPRENGER, F.E.; FEHER, A.; LAINETTI, F.F.; GASPAR, R.R.; NASCIMENTO, F.C.; SILVA, L.G.A.; HARADA, J.; BRAGA, A.; RODRIGUES, M.; SAMPA, M.H.O.
Radiation technology has been used to control environmental pollution. The aim of these studies was to apply the electron beam radiation technology for controlling plastic pollution and environmental protection.
Development and construction of a mobile electron beam accelerator to treat and recycle industrial effluents in Brazil
2022 - CALVO, WILSON A.P.; SOMESSARI, SAMIR L.; DUARTE, CELINA L.; SPRENGER, FRANCISCO E.; FEHER, ANSELMO; LAINETTI, FABIANA de F.; GASPER, RENATO R.; BRAGA, ALCIDES; RODRIGUES, MARCOS; SAMPA, MARIA H.O.
In the world, there is a growing increase in the demand for water for human consumption, as well as the prioritization of the use of available water resources for public supply. The treatment of wastewater and industrial effluents by electron beam irradiation is a promising technique, however, not very widespread in Brazilian territory. The design and construction of a mobile unit by the Nuclear and Energy Research Institute (IPEN/CNEN), containing an electron beam accelerator of 0.7 MeV, 20 kW and 640 mm window is innovative to demonstrate the effects and positive results of this technology. The mobile unit will have as one of its main advantages the possibility of treating effluents in the place where the source is located, eliminating costs and bureaucratic problems associated with the transportation of waste, besides publicizing the technology in several places in the country. To implement the project, IPEN/CNEN has been consolidating partnerships with national and international companies. The resources for the development of the unit have been supplied by the Brazilian Innovation Agency (FINEP) and International Atomic Energy Agency, financing the “IAEA TC Project BRA1035 - Mobile electron beam accelerator to treat and recycle industrial effluents”. The Institute has associated with a specialized company (Truckvan Industry) in an innovation project for the unit design and development. Several meetings have been realized with the company and the International Atomic Energy Agency experts, aiming the compatibility of the design and the exchange of information necessary for the project development. The idealized project divides the cart in the following modules: a) control room and laboratory for technical and scientific dissemination of the technology; b) industrial electron beam accelerator, hydraulic units, ventilation system, cooler and bunker with irradiation device; and c) transformer and power source supply. A 3D model study of the control room and laboratory space was done to facilitate understanding the internal distribution of the laboratory analysis equipment (Gas Chromatography Mass Spectrometry, Total Organic Carbon and UV-Visible Spectroscopy). The irradiation system with electron accelerators allows treating different types of effluents. Depending on the effluent, the amount of ionizing radiation energy required for treatment may vary, as well as the amount of treated effluent per day. For the construction of the mobile unit, the estimated cost is about US$ 1.5 Million. The type of treated effluent, the treatment cost per m3/day and other information regarding the cost of maintenance and operation of the mobile unit are obtained from the Business Plan of the Mobile Unit.
Development of an irradiation system for production of gaseous radioisotopes and of a tomographic 2-D gamma scanning for industrial process troubleshooting in Brazil
2022 - CARDOZO, NELSON X.; HARAGUCHI, MARCIO I.; KIM, HAE Y.; SOMESSARI, SAMIR L.; FEHER, ANSELMO; NAPOLITANO, CELIA M.; CALVO, WILSON A.P.
Radioisotopes as radiotracers are used in analytical procedures to obtain qualitative and quantitative data systems, in physical and physicochemical studies transfers, and troubleshooting of industrial process plants in chemical and petrochemical companies. In the production of gaseous radioisotopes used as tracers in industrial process measurements, argon-41 (41Ar) and krypton-79 (79Kr) stand out because each has low reactivity with other chemical elements. 41Ar is a transmitter range with high-energy (1.29 MeV) and a high percentage of this energy transformation (99.1%), resulting in relatively small quantities required in relation to the other, for an efficient detection, even in large thicknesses components. In this sense, the aim of this study is to develop an irradiation system for gaseous radioisotope production in continuous scale, applied in industrial applications of emission tomography and flow measurement. The irradiation system may produce 41Ar with activity of 7.4×1011 Bq (20 Ci) per irradiation cycle, through the Reactor IEA-R1 with 4.5 MW and average thermal neutron flux of 4.71×1013 ncm−2s−1 to meet an existing demand in NDT and inspections companies, and even needed by the Radiation Technology Centre, at IPEN/CNEN. The irradiation system consists of an aluminium irradiation capsule, transfer lines, needle valves, ringed connections, quick connectors, manometer, vacuum system, dewar, lead shielding, storage and transport cylinders, among other components. The irradiation system was approved in the leakage and stability tests (bubble test, pressurization, evacuation and with leak detector equipment. In the experimental production obtaining 1.07×1011 Bq (2.9 Ci) of 41Ar, alanine dosimeters were distributed into various components of the irradiation system. In addition, exposure rates were determined in the lead shielding wall, in which the liquefied radioactive gas was concentrated, and in the storage and transport cylinders after 41Ar was transferred by the portable radiation meter. However, gamma scanning is a nuclear inspection technique widely used to troubleshoot industrial equipment in refineries and petrochemicals plants such as distillation columns and reactors. A sealed radiation source and detector move along the equipment, and the intensity readouts generate the density profile of the equipment. The result of gamma scan still consists of a simple 1-D density plot. In this work, we also present the tomographic gamma scanning that, using image reconstruction techniques, shows the result as a 2-D image of density distribution. Clearly, an image reveals more features of the equipment than a 1-D graph and many problems that could not be troubleshooted using the conventional technique can now be solved with this imaging technique. We use ART (Algebraic Reconstruction Technique) intercalated with total variation minimization filter. The use of total variation minimization leads to compressive sensing tomography, allowing to obtain good quality reconstruction from few irradiation data. We simulated the reconstruction of different density distributions. We applied the new technique to data obtained by irradiating with gamma rays phantoms that emulate industrial equipment. Finally, we present the result obtained by applying the innovative technique to real operating distillation column.
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.
Automation system for quality control in manufacture of iodine-125 sealed sources used in brachytherapy
2011 - SOMESSARI, SAMIR L.; FEHER, ANSELMO; SPRENGER, FRANCISCO E; ROSTELATO, MARIA E.C.M.; MOURA, JOAO A.; COSTA, OSVALDO L.; CALVO, WILSON A.P.
The aim of this work is to develop an automation system for Quality Control (QC) in the production of iodine-125 sealed sources, after undergoing the process of Laser Beam Welding (LBW). These sources, also known as iodine-125 seeds are used, successfully, in the treatment of cancer by brachytherapy, with low-dose rates. Each small seed is composed of a welded titanium capsule with 0.8 mm diameter and 4.5 mm in length, containing iodine-125 adsorbed on an internal silver wire. The seeds are implanted in the human prostate to irradiate the tumor and treat the cancerous cells. The technology to automate the quality control system in the manufacturing of iodine-125 seeds consists in developing and associate mechanical parts, electronic components and pneumatic circuits to control machines and processes. The automation technology for iodine-125 seed production developed in this work employs Programmable Logic Controller (PLC), step motors, drivers of control, electrical-electronic interfaces, photoelectric sensors, interfaces of communication and software development. Industrial automation plays an important role in the production of Iodine-125 seeds, with higher productivity and high standard of quality, facilitating the implementation and operation of processes with Good Manufacturing Practices (GMP). Nowadays, the Radiation Technology Center at IPEN-CNEN/SP imports 36,000 iodine-125 seeds per year and distributes them for clinics and hospitals in the country. However, the Brazilian potential market is of 8,000 iodine-125 seeds per month. Therefore, the local production of these radioactive seeds has become a priority for the Institute, aiming to reduce the price and increase the supply to the population in Brazil.