Use of calcium alginate beads and Saccharomyces cerevisiae for biosorption of 241Am.

Calcium alginate beads, inactivated Saccharomyces cerevisiae and inactivated S. cerevisiae immobilized in calcium alginate beads (S. cerevisiae-calcium alginate beads) are examined as potential biosorption materials as regards their capacity to remove 241Am. In this study, initial experiments were carried out to evaluate the effects of pH (2 and 4) and 241Am initial concentration: 75, 150, and 300 Bq mL-1. The experiments were conducted in a batch reactor. Higher removal capacity was observed at pH 2 with the use of S. Cerevisiae, whereas pH 4 performed better for the essays with calcium alginate beads and S. Cerevisiae-calcium alginate beads. The pseudo-first-order kinetic model described the kinetics of biosorption. Calcium alginate was the adsorbent of choice to further experiments with synthetic organic liquid waste. A lower removal rate was observed in the organic waste, although calcium alginate beads have also been able to achieve high sorption capacity in less than 4 h. With the organic waste, the highest value of sorption capacity of 241Am was 4.38 × 10-7 mmol g-1 with an initial 241Am concentration of 2.31 × 10-8 mmol L-1.

RADIATION EXPOSURE DURING SPINE SURGERY USING C-ARM FLUOROSCOPY.

OBJECTIVE: To evaluate the radiation dose received by staff in spine surgeries, including those who are not considered occupationally exposed workers. METHODS: All spinal surgeries performed in the same department during a period of 12 months were evaluated with regard to the exposure of surgeons, scrub nurses, and auxiliary personnel working in the operating room to radiation from C-arm fluoroscopy. Radiation was measured by 15 film badge dosimeters placed on the professionals' lapels, gloves, and room standardized sites. The films were analyzed in the dosimetry laboratory by collections per period. RESULTS: During the 12 months, 81 spinal surgeries were performed by the same team, with surgical times ranging from 1 to 6 hours. The total radiation dose ranged from 0.16 mSv to 2.29 mSv depending on the dosimetry site. The most exposed site was the wrist of the main surgeon. CONCLUSION: The results showed that in the spinal surgeries in our setting, the radiation doses are low and within legal limits. Nevertheless, constant training of professionals is essential for radiation protection of medical staff and patients. Level of evidence I/b, exploratory cohort study.

OBJETIVO: Avaliar a dose de radiação recebida pela equipe cirúrgica em cirurgias de coluna, incluindo entre aqueles que não são considerados trabalhadores com exposição ocupacional. MÉTODO: Todas as cirurgias de coluna realizadas num mesmo departamento num período de 12 meses foram avaliadas quanto à exposição dos cirurgiões, enfermeiros/instrumentadores e auxiliares trabalhando na sala cirúrgica à radiação do fluoroscópio tipo "C-arm". A radiação foi medida por 15 dosímetros de filme posicionados nas lapelas, luvas dos profissionais e também em pontos padronizados da sala. Os filmes foram analisados no laboratório de dosimetria em coleções por período. RESULTADOS: Durante 12 meses, 81 cirurgias de coluna foram realizadas pela mesma equipe, e cada cirurgia durou entre 1 e 6 horas. A dose total de radiação variou de 0,16 mSv a 2,29 mSv dependendo do local de mensuração. O local com maior exposição foi o punho do cirurgião principal. CONCLUSÃO: Os resultados mostraram que nas cirurgias de coluna no nosso serviço, as doses de radiação foram baixas e dentro dos limites legais. Porém, o treinamento dos profissionais é essencial para a proteção contra a radiação dos profissionais de saúde e seus pacientes. Nível de evidência I/b, estudo de coorte exploratório.

Radiation exposure during spine surgery using c-arm fluoroscopy / Exposiçao a radiação durante cirurgias de coluna com radisocopia

ABSTRACT Objective: To evaluate the radiation dose received by staff in spine surgeries, including those who are not considered occupationally exposed workers. Methods: All spinal surgeries performed in the same department during a period of 12 months were evaluated with regard to the exposure of surgeons, scrub nurses, and auxiliary personnel working in the operating room to radiation from C-arm fluoroscopy. Radiation was measured by 15 film badge dosimeters placed on the professionals' lapels, gloves, and room standardized sites. The films were analyzed in the dosimetry laboratory by collections per period. Results: During the 12 months, 81 spinal surgeries were performed by the same team, with surgical times ranging from 1 to 6 hours. The total radiation dose ranged from 0.16 mSv to 2.29 mSv depending on the dosimetry site. The most exposed site was the wrist of the main surgeon. Conclusion: The results showed that in the spinal surgeries in our setting, the radiation doses are low and within legal limits. Nevertheless, constant training of professionals is essential for radiation protection of medical staff and patients. Level of evidence I/b, exploratory cohort study.

RESUMO Objetivo: Avaliar a dose de radiação recebida pela equipe cirúrgica em cirurgias de coluna, incluindo entre aqueles que não são considerados trabalhadores com exposição ocupacional. Método: Todas as cirurgias de coluna realizadas num mesmo departamento num período de 12 meses foram avaliadas quanto à exposição dos cirurgiões, enfermeiros/instrumentadores e auxiliares trabalhando na sala cirúrgica à radiação do fluoroscópio tipo "C-arm". A radiação foi medida por 15 dosímetros de filme posicionados nas lapelas, luvas dos profissionais e também em pontos padronizados da sala. Os filmes foram analisados no laboratório de dosimetria em coleções por período. Resultados: Durante 12 meses, 81 cirurgias de coluna foram realizadas pela mesma equipe, e cada cirurgia durou entre 1 e 6 horas. A dose total de radiação variou de 0,16 mSv a 2,29 mSv dependendo do local de mensuração. O local com maior exposição foi o punho do cirurgião principal. Conclusão: Os resultados mostraram que nas cirurgias de coluna no nosso serviço, as doses de radiação foram baixas e dentro dos limites legais. Porém, o treinamento dos profissionais é essencial para a proteção contra a radiação dos profissionais de saúde e seus pacientes. Nível de evidência I/b, estudo de coorte exploratório.

A New Storage Facility for Institutional Radioactive Wastes at IPEN.

IPEN, the Nuclear and Energy Research Institute in Sao Paulo, Brazil, has been managing the radioactive wastes generated in its own activities of research and radioisotope production as well as those received from many radioisotope users in the country since its start up in 1958. Final disposal options are presently unavailable for the wastes that cannot be managed by release after decay. Treated and untreated wastes including disused sealed radioactive sources and solid and liquid wastes containing radionuclides of the uranium and thorium series or fission and activation products are among the categories that are under safe and secure storage. This paper discusses the aspects considered in the design and describes the startup of a new storage facility for these wastes.

Optimization of radioactive waste storage.

In several countries, low-level radioactive wastes are treated and stored awaiting construction and operation of a final repository. In some cases, interim storage may be extended for decades requiring special attention regarding security issues. The International Atomic Energy Agency (IAEA) recommends segregation of wastes that may be exempted from interim storage or ultimate disposal. The paper presents a method to optimize the decision making process regarding exemption vs. interim storage or ultimate disposal of these wastes.