[en] Niobium, phosphate, coal and gold mining facilities have been selected as case studies with the aim of identifying possible sources of radiological impact during and after cessation of industrial operations. The results have shown that acid drainage, as well as chemical processing of mineral ores, constitute relevant impact indicators for present-day and future scenarios. The possible use of solid wastes abandoned at the end of the operations represents a long-term radiological concern. Therefore, it is necessary that Brazilian legislation for environmental licensing be revised taking into account the potential environmental and radiological impacts caused by these industries and establishing remedial procedures for waste storage areas in the existing sites. The indicators developed and procedures carried out can be used in screening for decisions on the adoption of regulatory requirements for practices at such types of installations

[en] The Brazilian production of bottled mineral water is about 560 million litres per year. The states of Sao Paulo, Rio de Janeiro, Minas Gerais and Pernambuco are responsible for more than 65% of the total production. Over twenty samples of bottled mineral waters from these states were analysed for ²²⁶Ra, ²²⁸Ra and ²¹⁰Pb content. Mean values of 27 mBq.l^-1 for ²²⁶Ra and 77 mBq.l^-1 for ²¹⁰Pb were found. ²²⁸Ra was found in only two samples and the highest value was 300 mBq.l^-1. Dose calculations were performed in order to evaluate the relative importance of the radionuclides to the radiation exposure of the Brazilian population. Based upon the production rate and the measured concentrations, collective committed effective doses per year of 1.5 manSv for ²²⁶Ra. 1.4 manSv for ²²⁸Ra and 17 manSv for ²¹⁰Pb were obtained. These results show that the ²¹⁰Pb is the main contributor to radiation exposure of the population because of their ingestion of bottled mineral water. (author)

[en] Over the first five years of operation of the Brazilian uranium open mine and mill facilities, a study was carried out in order to assess the influence of the different sources on the increase of ²²⁶Ra and ²³⁸U surface water concentrations and to the dose commitment to the critical group. The highest contribution was found to be from the waste rock because of its availability for leaching processes, facilitated by the pyrite content of the rock and the high rainfall in the region. The ready leaching of radionuclides from the ores by rainwater calls attention to the fact that even during prospecting, increases of ²²⁶Ra and ²³⁸U in the environment can occur. One can conclude from this study that whenever a high rainfall occurs together with a high pyrite content, mining as a whole is the most important activity of the uranium industry as far as doses to members of the public are concerned. (author)

[en] The Institute of Radiation Protection and Dosimetry (IRD), from the Brazilian Nuclear Energy Commission (CNEN), holds a singular position in the nuclear energy and radiation protection areas in Brazil. It develops applied researches to support the licensing and control of nuclear and radioactive installations in the country with the aim to protect members of the public, workers and patients against the undesirable effects of ionizing radiation. Doing so, the IRD contributes to the safe development and implementation of nuclear technologies in Brazil. One of the values of the IRD is to keep track of the state of art methodologies and researches in the different areas related to radiation protection, dosimetry and metrology upgrading its expertise to support the regulator during the licensing process and to discuss with the operator adequate safety solutions to solve any potential relevant radiological issue. Training of professionals of the nuclear area, by means of on-going regular courses graduate academic courses is also in the scope of IRD activities. In this context the IRD promotes discussions to spotlight the research trends and demands of the private and public sectors in those fields. This paper summarizes the most relevant issues on the perspectives of environmental radiation protection and radioecology in Brazil. The elements in this paper come from a workshop that was organized by the IRD and sponsored by CNEN and by the Brazilian National Council of Research and Technology (CNPq) that took place in Rio de Janeiro in November of 2004. It is expected that the products of this workshop will give the scientific and technical communities elements to help in the development of their research aligned with the needs of the country in these areas. In terms of the institute perspective the challenge that was pointed out during the workshop and to be faced by the institution was to find appropriate means to connect all its activities in a logical framework in order to find the adequate synergism between research and regulatory activities, that allow IRD to give support to the decision making process in the nuclear licensing process and to assist its stakeholders in a growing demand scenario, avoiding conflict of interest. (author)

[en] This work addresses the evaluation of the radiological environmental impacts associated to non-nuclear mining activities in Brazil. A study case on a niobium industry located at Minas Gerais State - south east region of the country - was carried out. It has been pointed out that the desliming, flotation and metallurgical operations were the main phases in radioactive wastes generation. However, the acid leaching of the ore removed large amounts of radionuclides from the host minerals (especially ²²⁶Ra and ²²⁸Ra) turning them out be in a more labile conditions and more available for remobilization processes. An estimated value of 0.26 mSv/y was obtained for the equivalent effective dose for an adult ingesting irrigated vegetables as a consequence of the radionuclides released with the liquid effluents. (author) 9 refs, 3 figs, 4 tabs

No abstract available

[en] The mining and milling of ores with significant amounts of uranium and thorium associated to the main ore has the potential to pose undue health risks to members of the general public and workers. In order to assess the status of this problem in the Brazilian non-uranium mining industries a comprehensive investigation project has been undertaken. The adopted methodology was based on the detailed analysis of each investigated industry operational flowplan, mass balance calculations, risk assessment (operational and post-operational scenarios taken into account) and environmental management principles. This papers addresses the main issues arising from the investigation effort, reports the most relevant conclusions and states the future studies to be implemented. It could be observed that these industries have the potential to cause relevant radiological impacts and must be regulated/controlled as to avoid these problems. (author)

[en] Mining and processing activities dealing with mineral ores containing associated uranium and thorium series elements can make these radionuclides available in their products, byproducts and in the environment, leading to the enhancement of the exposure of the public to natural radiation. Niobium, phosphate, coal and gold plants have been selected as case studies, aiming to identify possible radiological impact sources during and after ceasing the operation on these units. The dose assessment results for present and future exposures scenarios confirm these mining industries as activities potentially enhancing exposure to natural radiation. Thus, the legislation for environmental licensing must be reviewed in order to take into account the potential environmental radiological impact caused by these activities, as well as the establishment of remediation procedures for waste storage areas in the existing sites. (author)

[en] This paper discusses the difficulties in applying the prevailing radiation protection concepts in dealing with TENORM issues. The Brazilian experience is presented and the regulatory framework is presented. It is concluded that exemption criteria may not be the best way to address activities involving such kind of materials, although they may serve as reference values, along with dose estimates, to determine the extent in which individual TENORM industries shall be subjected to environmental impact assessment protocols. (author)

[en] Measurements regarding the population exposure were performed in Goiania after the radiological accident as well as studies on resuspension and redeposition of ¹³⁷Cs in urban areas, on the contribution of soil splash to the ¹³⁷Cs uptake by leafy vegetables and on the transfer of ¹³⁷Cs from soil to chicken meat and eggs. Periodical street dust sampling was used to follow-up the spreading of the radionuclide in the city. The results do not indicate a measurable spreading of this radionuclide throughout the city from the contaminated areas, but resuspension can lead to significant local contamination of agricultural products, equipment, structures, etc. (author)