RESUMO
Located in the south-western part of Brazil, the state of Rio de Janeiro is geotectonically contained within a complex structural province that resulted in the amalgamation of the Western Gondwana Paleocontinent. To undertake an extensive radiological characterization of this complex geological province and investigate the influence of bedrock, soil type and soil chemical-physical characteristics on natural radionuclide levels in soils, 259 surface soil samples were collected that encompassed the main soil types and geological formations throughout the state. Gamma spectrometry analysis of the samples resulted in median values of 114 Bq.kg-1for 40K, 32 Bq.kg-1 for 226Ra and 74 Bq.kg-1 for 228Ra. The median value for 226Ra was similar to the world median value for soils, the 40K value was well below the worldwide value, and that for 228Ra exceeded the world median value. The intense weathering caused by the high rainfall rates and high temperatures may be responsible for the low levels of 40K in the soils, of which the strongly acidic and clayey soils are markedly K-depleted. A soil from a high-grade metamorphic rock (granulite) presented the lowest 226Ra (18 Bq.kg-1) content, whereas the highest levels for 226Ra (92 Bq.kg-1) and 228Ra (139 Bq.kg-1) were observed in a young soil enriched in primary minerals (Leptsol). A lowland soil (Gleysol) showed the highest median of 40K (301 Bq.kg-1). Strongly acidic soils tended to present high amounts of 226Ra, and sandy soils tended to contain low levels of 228Ra. The external radiation dose indicates that the state has a background radiation level within the natural range.
Assuntos
Monitoramento de Radiação , Poluentes Radioativos do Solo/análise , Solo/química , Radiação de Fundo , Brasil , Radioisótopos de Potássio/análise , Radioatividade , Rádio (Elemento)/análise , Tório/análiseRESUMO
In the aftermath of the devastating Haitian earthquake, we became the primary relief service for a large group of severely injured earthquake victims. Finding ourselves virtually isolated with extremely limited facilities and a group of critically injured patients whose needs vastly outstripped the available resources we employed a disaster triage system to organize their clinical care. This report describes the specific injury profile of this group of patients, their clinical course, and the management philosophy that we employed. It provides useful lessons for similar situations in the future.
Assuntos
Planejamento em Desastres/organização & administração , Terremotos , Serviços Médicos de Emergência/organização & administração , Traumatismo Múltiplo/terapia , Triagem/organização & administração , Ferimentos e Lesões/terapia , Feminino , Haiti/epidemiologia , Humanos , Masculino , Incidentes com Feridos em Massa , Traumatismo Múltiplo/epidemiologia , Úlcera por Pressão/epidemiologia , Úlcera por Pressão/terapia , Sepse/epidemiologia , Ferimentos e Lesões/epidemiologiaRESUMO
Vegetables grown with phosphate fertilizer (conventional management), with bovine manure fertilization (organic management) and in a mineral nutrient solution (hydroponic) were analyzed and the concentrations of (238)U, (226)Ra and (228)Ra in lettuce, carrots, and beans were compared. Lettuce from hydroponic farming system showed the lowest concentration of radionuclides 0.51 for (226)Ra, 0.55 for (228)Ra and 0.24 for (238)U (Bq kg(-1) dry). Vegetables from organically and conventionally grown farming systems showed no differences in the concentration of radium and uranium. Relationships between uranium content in plants and exchangeable Ca and Mg in soil were found, whereas Ra in vegetables was inversely correlated to the cation exchange capacity of soil, leading to the assumption that by supplying carbonate and cations to soil, liming may cause an increase of U and a decrease of radium uptake by plants. The soil to plant transfer varied from 10(-4) to 10(-2) for (238)U and from 10(-2) to 10(-1) for (228)Ra.
Assuntos
Agricultura , Rádio (Elemento)/análise , Urânio/análise , Verduras/metabolismo , Daucus carota/metabolismo , Fabaceae/metabolismo , Lactuca/metabolismo , Rádio (Elemento)/metabolismo , Urânio/químicaRESUMO
The objective of the Environmental Radiological Monitoring Control programme carried out by the Institute of Radiation Protection and Dosimetry (IRD) in Brazil is to verify the licensee's compliance with the requirements for environmental monitoring of Brazilian facilities. The Joint Sampling Programme (JSP) is just one part of the control programme. In order to verify that the data reported by the licensees is representative and legitimate, this programme verifies sampling procedures, accuracy and precision of the data and the changes in the environmental conditions. This paper discusses the main findings of this programme that allowed IRD to optimize its available resources to control the monitoring of the eight facilities in Brazil.
Assuntos
Exposição Ambiental/análise , Monitoramento de Radiação/métodos , Monitoramento de Radiação/normas , Gestão da Segurança/métodos , Gestão da Segurança/normas , Brasil , Controle de Qualidade , Doses de Radiação , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
Concentrations of Al, Cd, Cr, Cu, Mn, Ni, Pb, U and Zn were determined in vegetables (leafy vegetables, fruit, root, grain and cereal), derived products (sugar, coffee, manioc flour, wheat flour, corn flour, and pasta) and animal products (meat, fish, milk) most frequently consumed by adult inhabitants of Rio de Janeiro city. A total of 90 samples were analyzed using inductively coupled plasma mass spectrometry (ICPMS) as the principal method following sample dissolution by dry and wet ashing. Generally, highest contributions for the intake of micronutrients (Cu, Mn, Ni and Zn) arise from bean, rice and wheat flour consumption. Meat, cow milk and the flours, wheat and manioc, are major sources of Al, Cd, Pb and U intake. The daily intake of nine elements via foodstuffs was estimated as: 3.4x10(-4) mg of U, 1.8x10(-3) mg of Cd, 2.8x10(-2) mg of Pb, 2.3x10(-2) mg of Cr, 8.9x10(-2) mg of Ni, 1.12 mg of Cu, 2.5 mg of Mn, 3.5 mg of Al and 4.8 mg of Zn. The intake of toxic elements ranged between 2.7% (Cd) and 30% (U) of the provisional tolerable daily intake and reference dose values indicating that food consumption is, at present, no critical factor for the uptake of these toxic metals, in the population studied here. Concerning micronutrients, the recommended values of daily intake of Cu and Mn are conveniently supplied by the diet; however, for Cr and Zn they are lower than the recommend daily allowance. Due to high metal concentrations and consumption rates, black bean is the foodstuff that provided the highest ingestion rates of Cu, Mn, Ni and Zn (36-60% of the reference dose), being therefore a very important source of micronutrient supply.
Assuntos
Dieta , Monitoramento Ambiental/estatística & dados numéricos , Análise de Alimentos/estatística & dados numéricos , Oligoelementos/análise , Adulto , Brasil , Cidades , Humanos , Espectrometria de Massas , Política NutricionalRESUMO
Ground water from Região dos Lagos, a coastal area of Rio de Janeiro state, was analysed for (226)Ra, (228)Ra, (222)Rn, (238)U, major ion concentrations, and physico-chemical parameters were also measured. Concentrations values ranged from <0.002 to 0.492 Bq l(-1) for (226)Ra, from <0.01 to 1.50 Bq l(-1) for (228)Ra and from < 1.0 x 10(-4) to 8.0 x 10(-2) Bq l(-1) for (238)U. Detectable (222)Rn concentrations (>3 Bq l(-1)) were found only in two samples. The spatial distribution of Ra concentration delineated one distinct area and some hot spots with high Ra concentration. Low pH value is the most important water parameter linked to high radium concentration. This is probably related to limited adsorption of radium on soil ferric oxides and hydroxides at low pH range. There was a significant correlation between uranium concentrations and electrical conductivity values, and also between uranium concentrations and concentrations of Ca, Mg, Na, K, and Cl, indicating sea water impact. Uranium concentrations were lower than maximum contaminant level for drinking water, whereas 17 out of the 88 ground water samples had levels of radium that exceeded the maximum contaminant level for tap water. The total annual effective dose for adult due to the water consumption reaches values up to 0.8 mSv.
Assuntos
Rádio (Elemento)/análise , Radônio/análise , Poluentes Radioativos do Solo/análise , Urânio/análise , Poluentes Radioativos da Água/análise , Abastecimento de Água , Adulto , Brasil , Exposição Ambiental , Monitoramento Ambiental , Humanos , Medição de RiscoRESUMO
The concentrations of the naturally occurring radionuclides 232Th, 238U, 210Pb, 226Ra and 238Ra were determined in the vegetables (leafy vegetables, fruit, root, bean and rice) and derived products (sugar, coffee, manioc flour, wheat flour, corn flour and pasta) consumed most by the adult inhabitants of Rio de Janeiro City. A total of 88 samples from 26 different vegetables and derived products were analyzed. The highest contribution to radionuclide intake arises from bean, wheat flour, manioc flour, carrot, rice, tomato and potato consumption. The estimated daily intakes due to the consumption of vegetables and derived products are 1.9 mBq of 232Th (0.47 microg), 2.0 mBq of 238U (0.17 microg), 19 mBq of 236Ra, 26 mBq of 210Pb and 47 mBq of 228Ra. The estimated annual effective dose due to the ingestion of vegetables and their derived products with the long-lived natural radionuclides is 14.5 microSv. Taking into account literature data for water and milk from Rio de Janeiro the dose value increases to 29 microSv, with vegetables and derived products responsible for 50% of the dose and water for 48%. 210Pb (62%) and 228Ra (24%) were found to be the main sources for internal irradiation.
Assuntos
Exposição Ambiental , Contaminação de Alimentos , Radioisótopos/farmacocinética , Verduras , Brasil , Monitoramento Ambiental , Humanos , Radioisótopos/análise , População UrbanaRESUMO
Unexpected high 228Ra concentrations, up to 2 Bq 1(-1), were found in waters of a coastal lagoon close to a monazite sand separation plant. Due to their use as process waters in this plant, the initial supposition was a contamination related to its operation. However, it was concluded that these abnormal radium concentrations had a natural origin, springs at the lagoon head area with high 228Ra and 226Ra concentrations. The strong relationship among radium and light rare-earth elements (LREEs), the observed 228Ra/226Ra activity ratio and the rare-earth element pattern in the spring waters suggested that monazite is the main source of nuclides for water, indicating the disturbance of monazite chemical stability by the combined effects of low pH and high salinity. Both factors combined allow relatively low mobility of thorium, but, on the other hand, a relatively high mobility of radium and LREEs.