The rupture of the Córrego do Feijão Dam close to Brumadinho municipality is one of the recent and most devastating environmental disaster in Brazil. This study aims to report the results of metal determinations and acute toxicity assays... more
The rupture of the Córrego do Feijão Dam close to Brumadinho municipality is one of the recent and most devastating environmental disaster in Brazil. This study aims to report the results of metal determinations and acute toxicity assays of mining tailing samples collected 5 days after the dam rupture. Concentrations of As, Cu and Ni in site 1 (close to the dam); concentrations of Cu, Zn and Pb in site 2 (Solo Sagrado) and As, Cd and Cr in the three replicates of site 3 (Mario Campos municipality) were higher than TEL reference value. The Cd concentration in of site 1, and As, Cd and Ni concentrations in of site 2 were higher than the PEL reference value, indicating effective effects of these metals to biota. Corroborating with previous studies, the Uranium contamination was detected close to Solo Sagrado. However, the evaluation of radionuclides came to the absence of relevant radioactivity. Regarding the ecotoxicological assays, survivor percentages of Daphnia similis were lower t...
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Natural radioactivity is ubiquitous in the environment mainly due to the presence of the nuclides from the uranium and thorium series and 40K. Although in the South Hemisphere nuclear tests have been fewer in number than that in the... more
Natural radioactivity is ubiquitous in the environment mainly due to the presence of the nuclides from the uranium and thorium series and 40K. Although in the South Hemisphere nuclear tests have been fewer in number than that in the North, artificial radionuclides can also be found spread at ground level. In this study, the activity concentrations of natural nuclides from the uranium and thorium series, 40K and the artificial 137Cs were determined in a sediment core with 42 cm depth collected in the middle of the Salesópolis reservoir, located in the Metropolitan Region of São Paulo city (SPMR). The Usina Parque Rio Tietê reservoir belongs to the Alto do Tietê system for the capture, storage and treatment of water for SPMR. Therefore, the quality of the water and sediments of this dam is of great importance. The activity concentrations were measured by gamma spectrometry. Samples were measured and saved at regular intervals at a maximum of 160 000 seconds. The gross area were determ...
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This study aimed to assess the bioaccumulation of Pb and induction of metallothionein-like proteins (MT) in Callinectes danae through single and combined dietary and waterborne exposures. Male C. danae individuals were collected in the... more
This study aimed to assess the bioaccumulation of Pb and induction of metallothionein-like proteins (MT) in Callinectes danae through single and combined dietary and waterborne exposures. Male C. danae individuals were collected in the south area of the Cananéia-Iguape-Peruíbe Protected Area (APA-CIP), in São Paulo State, Brazil. After an acclimatization period, exposure assays were performed during 7 and 14 days, at two Pb concentrations (0.5 e 2.0 µg/g) in 4 treatments: 1) control; 2) contaminated water only; 3) contaminated food only; 4) contaminated water and food. The results indicate that C. danae is highly tolerant to Pb exposure at the evaluated concentrations. In gills, Pb bioaccumulation is more dependent of water efflux and time of exposure (higher Pb values). However, pathways act simultaneously in the induction of MT expression in this tissue. The decreases in Pb accumulation in the combined treatments and MT increases after 14 days in gills suggests that these proteins...
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The outsourcing informal home practices adopted in jewelry and fashion jewelry chain can cause toxic substance elimination in the effluents and raise a concern for its environmental impact. This study evaluates if this informal work... more
The outsourcing informal home practices adopted in jewelry and fashion jewelry chain can cause toxic substance elimination in the effluents and raise a concern for its environmental impact. This study evaluates if this informal work alters the concentration of potentially toxic elements (PTEs: As, Cd, Cr total and Cr-VI, Cu, Hg, Ni, Pb, Sn, and Zn) in the sewage network. The sanitary sewage samples (n = 540) were collected in 15 manholes during two campaigns in three different areas of Limeira-SP, Brazil (industrial area, with informal work and without known industrial/informal activity). The sewage sludge (n = 12), raw (n = 12), and treated sewage (n = 12) were collected in two wastewater treatment plants (WWT: AS and TATU) operating with different treatment process. The PTE determination was performed by ICP-OES, direct mercury analysis, and UV-Vis spectroscopy. Cr-VI, Cu, Ni, and Zn were the only elements above the quantification limit. Four samples exceeded Cu or Zn values permi...
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Foi avaliada a composição química e percentual de adequação das dietas coletadas por meio da porção em duplicata de 36 servidores do Instituto Nacional de Pesquisas da Amazônia (INPA). De acordo com os resultados obtidos, verificou-se uma... more
Foi avaliada a composição química e percentual de adequação das dietas coletadas por meio da porção em duplicata de 36 servidores do Instituto Nacional de Pesquisas da Amazônia (INPA). De acordo com os resultados obtidos, verificou-se uma diversificação de alimentos frequentemente consumidos, dentre eles: açúcar (91,7%), arroz (80,6%), café (77,8%), leite (72,3%), carne bovina e pão (63,9%), farinha de mandioca (58,4%), batata inglesa (55,6%), feijão (50,04%), aves (38,9%), banana, cenoura e embutidos (33,4%), ovo, refrigerantes e tomate (30,6%). Considerando as recomendações nutricionais para a faixa etária de 25 a 50 anos, as adequações calóricas foram 40% e 52,7% para homens e mulheres respectivamente, protéica 76,4% (homens) e 96,3% (mulheres). Os minerais Ca, Mg e Zn (homens) apresentaram adequação inferior a 50%, enquanto que o Fe apresentou adequação de 89,1% (homens) e 59.4% (mulheres). Os minerais Na, Cu, Cl, Cr e I apresentaram valores acima do recomendado em ambos os sexo...
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O camu-camu, caçari, ou araçá d'água (Myrciaria dubia (H.B.K) McVaugh) é um arbusto da família Myrtaceae, disperso em quase toda a Amazônia. É uma espécie tipicamente silvestre mas com grande potencial econômico e nutricional.... more
O camu-camu, caçari, ou araçá d'água (Myrciaria dubia (H.B.K) McVaugh) é um arbusto da família Myrtaceae, disperso em quase toda a Amazônia. É uma espécie tipicamente silvestre mas com grande potencial econômico e nutricional. Entretanto, no que se refere a elementos minerais, poucas informações são disponíveis na literatura. Considerando a essencialidade dessas informações na nutrição humana e objetivando contribuir na elaboração de uma Tabela de composição de alimentos a nível regional e nacional, determinou-se os elementos minerais em algumas populações de camu-camu, pela Técnica de Ativação com Nêutrons Instrumental. Verificou-se que em relação aos macro elementos minerais, nos frutos de camu-camu analisados, as maiores concentrações foram para potássio, com uma variação de (62,6±0,4 a 144,1±08 mg %) e cálcio (9,5±0,3 a 10,6±0,5 mg%). A concentração de sódio nos frutos foi baixa (90,7±16,5 µg%). A população Uatumã-9 apresentou maiores concentrações de zinco (472,0±8,3µg%), m...
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A sediment core was studied to characterize the influences of Holocene sea-level variations in the Barra Seca River valley, in the Atlantic rainforest, Linhares, Espírito Santo, southeastern Brazil. Biological proxies (pollen, spores, and... more
A sediment core was studied to characterize the influences of Holocene sea-level variations in the Barra Seca River valley, in the Atlantic rainforest, Linhares, Espírito Santo, southeastern Brazil. Biological proxies (pollen, spores, and sponge spicules), 14C dating, granulometry, δ13C, δ15N, C/N and major chemical elements revealed the establishment and the evolution of a paleo-estuary during the interval from ∼7700–585 cal BP. During the interval ∼7700–7000 cal BP, the study site was occupied by a bay-head delta, the inner portion of the paleo-estuary, presenting the most dense mangrove coverage of the entire record. In the interval ∼7000–3200 cal BP, the site was occupied by the central basin, possibly a consequence of the landward migration of the paleo-estuary. This interval presents reduced mangrove coverage, probably due to the permanent flooding of the valley. From ∼3200 cal BP, the marine influence at the site decreased probably as result of the seaward migration of the co...
Research Interests: Archaeology, Geology, Geochemistry, Oceanography, Palynology, and 6 moreRadiocarbon, Palaeoecology, Mangrove, Holocene, Estuary, and Bay
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... peixes Determination of mercury and methylmercury in fish and hair samples LucianaAparecida FARIAS1*, Déborah Inês Texeira FÁVARO, Marina Beatriz Agostini VASCONCELLOS ... Page 2. 452 Farias LA, Fávaro DIT, Vasconcellos MBA. ...
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No presente trabalho são apresentados valores de concentração para os elementos minerais Ca, Fe, Κ, Mn, Na, Se e Zn em alimentos convencionais e não convencionais da região Amazônica, obtidos por análise por ativação neutrônica... more
No presente trabalho são apresentados valores de concentração para os elementos minerais Ca, Fe, Κ, Mn, Na, Se e Zn em alimentos convencionais e não convencionais da região Amazônica, obtidos por análise por ativação neutrônica instrumental. As concentrações dos elementos minerais nos alimentos analisados, variaram, sendo que o potássio se sobressaiu com teores expressivos na jaca (caroço e polpa) e graviola. Dentre os minerais, o selênio foi o que apresentou menor concentração nos alimentos analisados. Entretanto, notadamente importantes foram as concentrações verificadas na graviola, pupunha fruto e palmito. De acordo com os resultados obtidos sugere-se a indicação dos mesmos na alimentação diária dos amazonenses e espera-se contribuir na elaboração de tabelas de composição de alimentos regional e nacional.
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The lagoon-estuary complex of Cananéia is located in the southern coast of São Paulo State. This preserved area composes a Biosphere Natural Reserve due to its environmental and cultural importance. The sediments from the South part of... more
The lagoon-estuary complex of Cananéia is located in the southern coast of São Paulo State. This preserved area composes a Biosphere Natural Reserve due to its environmental and cultural importance. The sediments from the South part of this system were sampled in two seasonal periods (summer and winter -2005). This region shows three different parts composed by Cananéia Sea (stations 1-6), Cubatão sea (stations 10-13) and Trapandé Bay (stations 7-9). The sediments in this region are composed mainly by sand fractions, but in some points the pelitic fraction is representative. Associated with the siltic and clay sediments it was possible to observe the presence of organic matter, with values higher than 10%, with important content in total and organic P in three points (stations 4, 9 and 11). These points showed the most important values of pelitic sediments and the highest values in summer period that represents the rainy period. The metalic elements showed values positively associat...
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The application of fertilizers and pesticides results in high residual concentrations of heavy metals in soils, as well as in accumulation of toxic substances in crops and natural water. Arsenic may accumulate in soil through the use of... more
The application of fertilizers and pesticides results in high residual concentrations of heavy metals in soils, as well as in accumulation of toxic substances in crops and natural water. Arsenic may accumulate in soil through the use of pesticides and application of synthetic fertilizers. The mobility of As in soils depends on several factors including redox potential, soil mineralogy, pH and the presence of other anions that compete with As for soil retention sites, for example, phosphate. Ingestion of inorganic arsenic, from drinking water is known to cause cancer. Studies in an area of Jundiai, São Paulo, with high arsenic levels in well natural water. The application of pesticides and phosphate fertilizers on a wide scale is a common agricultural practice. The intention of this study is to investigate the effects of mobility os As to the satured zone with contamination the aquifer. Based on data from the experiments, arsenate and phosphate adsorption, displayed similar adsorptio...
In order to better understanding geochemical and environmental processes and their possible changes due to anthropogenic activities trace metal analyses and their distribution in marine sediments are commonly undertaken. The present study... more
In order to better understanding geochemical and environmental processes and their possible changes due to anthropogenic activities trace metal analyses and their distribution in marine sediments are commonly undertaken. The present study reports result concerning the distribution of some major, trace and rare earth elements in the Santos estuarine marine sediments. Thirteen bottom sediment samples (SV0501 to SV0513) were collected in this estuary, including regions of São Vicente, Santos, Cubatão, Vicente de Carvalho and Santos' Bay, in the summer of 2005. Multielemental analysis was carried out by instrumental neutron activation analysis (INAA). For total mercury determination cold vapor atomic absorption technique (CV AAS) was employed. In both cases methodology validation was performed by certified reference material analyses. The results obtained for multielemental concentrations in the sediment samples were compared with NASC (North American Shale Composite) values. The co...
RESUMO O presente trabalho apresenta resultados de análise química de refeições (almoço) oferecidas pelo restaurante do COSEAS (Universidade São Paulo), por cinco dias não consecutivos. Essas refeições foram coletadas em triplicata, da... more
RESUMO O presente trabalho apresenta resultados de análise química de refeições (almoço) oferecidas pelo restaurante do COSEAS (Universidade São Paulo), por cinco dias não consecutivos. Essas refeições foram coletadas em triplicata, da mesma forma como oferecida para os usuários, sendo a seguir liofilizadas para as análises posteriores. No total, 15 amostras foram coletadas. A análise química de composição centesimal foi realizada segundo as técnicas padronizadas pela AOAC (1995). O conteúdo de alguns elementos minerais (Ca, Fe, K, Na, Se e Zn) foram determinados por análise por ativação neutrônica instrumental. A validação da metodologia foi feita por meio da análise dos materiais de referência certificados Oyster Tissue (NIST SRM 1566 b), Orchard Leaves (NIST SRM 1541) e Peach Leaves (NIST SRM 1547). A partir dos dados de concentração, calculou-se os valores de ingestão de cada nutriente correspondente a esta refeição (40% da ingestão diária total), que foram avaliadas segundo as ...
The phosphatic soils found in the northern part of the Rata island, in the Fernando de Noronha Archipelago, were formed by reaction of bird guano with weathered mafic rocks of the Quixaba Formation. Phosphate minerals identified include... more
The phosphatic soils found in the northern part of the Rata island, in the Fernando de Noronha Archipelago, were formed by reaction of bird guano with weathered mafic rocks of the Quixaba Formation. Phosphate minerals identified include crandallite as a major constituent. The unique guano signature preserved in soil is characterized by high levels of Cu, Pb, Zn, As, U, and Sr. On the other hand, the inheritance of the geochemical signature of the nepheline-basalts is demonstrated by the anomalous concentrations of Ba, Nb, Ta, Cr, Hf, V and Zr in soils, and by the remarkable similarity between REE patterns in rock and soils.
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Estudos sobre composição de alimentos largamente consumidos pela população são fundamentais para estabelecer se uma determinada dieta é adequada em relação aos nutrientes essenciais. No presente trabalho, são apresentados resultados de... more
Estudos sobre composição de alimentos largamente consumidos pela população são fundamentais para estabelecer se uma determinada dieta é adequada em relação aos nutrientes essenciais. No presente trabalho, são apresentados resultados de análises de nutrientes realizadas em dietas representativas do consumo alimentar de trabalhadores de indústria de autopeças da cidade de São Paulo (homens de 19 a 56 anos), coletadas a partir da porção em duplicata de todos os alimentos e bebidas consumidos durante 3 dias consecutivos. Foram determinados os teores de proteínas, lipídeos, carboidratos, cinza, umidade, fibras alimentares e vitaminas B1, B2 e piridoxina em 24 dietas. Comparando-se os resultados obtidos com as novas recomendações (DRIs), verificou-se que as dietas dos trabalhadores atingiram adequação de 100% em carboidratos e 96% em proteínas e lipídeos. Em relação às fibras dietéticas, as dietas foram inadequadas, com apenas 4,2% de adequação. Todas as dietas foram adequadas em vitamina...
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Considerando-se que pouco se conhece sobre os constituintes nutricionais do açaí, determinou-se o teor de ferro no "vinho" pela técnica de Análise por Ativação com Nêutrons Instrumental. Foram analisadas amostras de açaí... more
Considerando-se que pouco se conhece sobre os constituintes nutricionais do açaí, determinou-se o teor de ferro no "vinho" pela técnica de Análise por Ativação com Nêutrons Instrumental. Foram analisadas amostras de açaí provenientes do Pará, assim como dos municípios de Anamã, Codajas, Tabatinga, Benjamin Constant, Parintins e Barcelos, AM. De acordo com os resultados obtidos, verificou-se que o peso médio dos frutos variaram de 0,83g a 2,04g e semente de 0,59g a 1,38 ± 0,13g. Verificou-se baixos teores de ferro com concentrações variando de 289,8 ± 37,8 μg a 1093,5 ± 22,0pg%, demonstrando que o açaí como fonte de ferro é pouco expressivo.
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ABSTRACT The objective of this study was to quantify major and trace elements present in sediments collected from the one of Brazil’s most important rivers, Tietê River. Sediments from 5 different sampling points (P0–P4), in 3 campaigns... more
ABSTRACT The objective of this study was to quantify major and trace elements present in sediments collected from the one of Brazil’s most important rivers, Tietê River. Sediments from 5 different sampling points (P0–P4), in 3 campaigns (2008/2009), from the headwaters to Suzano County upstream from São Paulo city were collected. X-ray fluorescence was applied for measuring total concentration of major elements and instrumental neutron activation analysis (INAA) for trace elements. The elements Cd, Hg and Pb were determined by atomic absorption spectrometry after digestion using the US EPA 3,051 procedure. These metal concentrations were compared to the PEL and TEL oriented values from CCME. The sampling sites P3 and P4, near industrialized areas, showed the highest concentrations for potentially bioavailable metals, mainly Pb and Hg. The results obtained by INAA were compared to upper continental crust values. A strong enrichment was found for the elements As, Br, Sb, Th, U and Zn. These results evidenced contamination by industrial effluents and sewage even relatively close to the Tietê River headwaters. The worst biological effects (acute toxicity) on benthonic organism Hyalella azteca were also observed at P3 and P4.
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A preirradiation separation procedure has been developed to separate Al, Cu, Mn, and V from biological materials. Chelex-100 resin is used as the separation medium, and the resin is irradiated directly. Three NIST biological Standard... more
A preirradiation separation procedure has been developed to separate Al, Cu, Mn, and V from biological materials. Chelex-100 resin is used as the separation medium, and the resin is irradiated directly. Three NIST biological Standard Reference Materials and five samples of human blood serum, obtained under carefully controlled conditions, have been analyzed by NAA following this separation.
Research Interests: Chemistry, Radiochemistry, Brazil, Medicinal Plants, Medicine, and 13 moreSnake venoms, Food Analysis, Humans, Hair, Neutron Activation Analysis, Lung, Trace Elements, Snake Venom, Chelating Agents, Medicinal Plant, Neutron Activation, Instrumental Neutron Activation Analysis (INAA), and Reference standards
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Research Interests: Geography, Spectroscopy, Developing Countries, Latin America, Mercury, and 14 moreElements, Absorption spectroscopy, Microanalysis, Absorption, Sorption, Chemical Analysis, Neutron Activation Analysis, Surface Waters, Absorption Spectra, Weyl semimetals, Elementary Particles, Fermions, Nucleons, and baryons
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Summary Santos Basin, located in Southwest Brazil, is considered the most important industrial region of the country. Among the industrial activities present, phosphate fertilizer plants are responsible for the production of 69 million... more
Summary Santos Basin, located in Southwest Brazil, is considered the most important industrial region of the country. Among the industrial activities present, phosphate fertilizer plants are responsible for the production of 69 million tons of phosphogypsum waste, which is stockpiled in the surrounding environment. This waste concentrates radionuclides of the natural series as well as rare earth elements originally present in
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The biological standard reference materials Orchard Leaves SRM 1571 and Oyster Tissue SRM 1566a was analysed by instrumental neutron activation analysis (INAA) at the International Centre for Environmental and Nuclear Sciences, Jamaica at... more
The biological standard reference materials Orchard Leaves SRM 1571 and Oyster Tissue SRM 1566a was analysed by instrumental neutron activation analysis (INAA) at the International Centre for Environmental and Nuclear Sciences, Jamaica at (ICEN) and at the Instituto de Pesquisas Energeticas e Nucleares (IPEN-CNEN/SP), Brazil. The comparison of the results with those obtained with the more powerful reactor are used
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Considerando-se a atual situação epidemiológica do Brasil em que a obesidade e as doenças crônico-degenerativas (doenças cardiovasculares, diabetes mellitus e câncer) passam a ser destaque em saúde pública, parece prudente a preocupação... more
Considerando-se a atual situação epidemiológica do Brasil em que a obesidade e as doenças crônico-degenerativas (doenças cardiovasculares, diabetes mellitus e câncer) passam a ser destaque em saúde pública, parece prudente a preocupação quanto à caracterização química dos alimentos regionais com potencial econômico e nutricional, em especial os de baixo teor calórico, como o palmito. Sendo assim, determinou-se a composição centesimal, fitato e elementos minerais (macro e micro) no palmito de pupunheira in natura e cozido. O palmito de pupunheira utilizado foi o da raça Pampa Hermosa, da Estação Experimental de Fruticultura da Coordenação de Pesquisas em Ciências Agronômicas (CPCA) do Instituto Nacional de Pesquisas da Amazônia (INPA), em Manaus (AM), coletado no período chuvoso, em janeiro de 1995. Tomou-se aleatoriamente 3,5 kg de palmito de 110 progênies de pupunha inerme, com 2 anos de idade, por ocasião do primeiro corte. As palmeiras foram cultivadas em Latossolo Amarelo, isent...
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Research Interests: Geology, Geochemistry, Physics, REE, Geoquímica, and 4 moreSoils, Pb isotopes, Solos, and Fernando De Noronha
This work focuses on the behaviour of mercury in lateritic soil profiles found in the Serra do Navio and Tartarugalzinhoareas of the State of Amapá in Northern Brazil. The Hg contents are high in the upper horizons of the soil... more
This work focuses on the behaviour of mercury in lateritic soil profiles found in the Serra do Navio and Tartarugalzinhoareas of the State of Amapá in Northern Brazil. The Hg contents are high in the upper horizons of the soil profiles(100–300 µg kg-1), and decrease to less than 100 µg kg-1 at depths of 200 or 300 cm. The higher
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The Rio Grande Reservoir, Southeast of the São Paulo Metropolitan Area (SPMA) supplies water for four counties (São Bernardo do Campo, São Caetano do Sul, Santo André and Diadema). It has been seriously a ffected by urban expansion, due... more
The Rio Grande Reservoir, Southeast of the São Paulo Metropolitan Area (SPMA) supplies water for four counties (São Bernardo do Campo, São Caetano do Sul, Santo André and Diadema). It has been seriously a ffected by urban expansion, due to chaotic urban occupation and improper use of the surrounding areas. In this study bottom sediment samples were collected, by using
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Laguna del Plata (Cordoba, Argentina) is a small saline lake connectedto Laguna Mar Chiquita. Its level fluctuations have changed notably throughthe centuries with both high level (HLP) and low level (LLP) periods. Theradionuclides 226 Ra... more
Laguna del Plata (Cordoba, Argentina) is a small saline lake connectedto Laguna Mar Chiquita. Its level fluctuations have changed notably throughthe centuries with both high level (HLP) and low level (LLP) periods. Theradionuclides 226 Ra and 210 Pb were analyzed in a core to determine datesand sedimentation rates. The elements As, Ba, Br, Co, Cr, Cs, Fe, Hf, Na,Rb, Sb, Sc, Se, Ta, Th, U, Zn, Zr and rare earth Ce, Eu, La, Lu, Nd, Sm, Tband Yb were determined by instrumental neutron activation analysis. Statisticalanalysis of elemental concentrations (cluster analysis) reflects the associationof the samples along the core according to the provenance of the sedimentsand if they had been deposited during HLP or LLP.
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A 72 cm long core was collected from Lagoa da Viração (LV), a small pond in the Fernando de Noronha island, northern Brazil. Sediments from the lower section of the core (20—72 cm depth) contain essentially mineral matter, while in the... more
A 72 cm long core was collected from Lagoa da Viração (LV), a small pond in the Fernando de Noronha island, northern Brazil. Sediments from the lower section of the core (20—72 cm depth) contain essentially mineral matter, while in the upper section (0—20 cm depth) mineral matter is mixed with organic matter. Lithogenic conservative elements — Si, Al, Fe, Ti, Co, Cr, Cu, Ba, Ga, Hf, Nb, Ni, Y, V, Zn, Zr and REE — exhibit remarkably constant values throughout the core, with concentrations similar to those of the bedrock. The vertical distribution of soluble elements — Ca, Mg, Na, K, P, Mn and Sr — is also homogeneous, but these elements are systematically depleted in relation to the bedrock. LOI, TOC, Br, Se, Hg and Pb, although showing nearly constant values in the lower section of the core, are significantly enriched in the upper section. The concentration profiles of Br and Se suggest that they may be accounted for by natural processes, related to the slight affinity of these elem...
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In the present study, sediment samples from the Tie tê River were evaluated for toxicity and trace meta ls (5 sampling sites). The studied region includes Salesó polis to Suzano and surroundings, a highly industri alized area. The study... more
In the present study, sediment samples from the Tie tê River were evaluated for toxicity and trace meta ls (5 sampling sites). The studied region includes Salesó polis to Suzano and surroundings, a highly industri alized area. The study involved toxicity evaluation (sedim ent, elutriate and pore-water) and the distribution of some major, trace and rare earth elements on sediments. Multielemental analysis was carried out by instrume ntal neutron activation analysis (INAA) and total mercur y by cold vapor atomic absorption technique (CV AAS). The concentration values obtained for the metals As , Cr, Hg and Zn in the sediment samples were compared to the Canadian Council of Minister of the Environment (CCME) oriented values (TEL and PEL). Regarding toxicity, whole sediments and elutriate fractions w ere evaluated using chronic assays for Ceriodaphnia dubia , while the pore water was carried out for Vibrio fischeri toxicity assays. These assays followed Brazilian Standardized Methods (A...
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Phosphogypsum, a waste by-product derived from the wet process production of phosphoric acid, represents a serious problem facing the phosphate industry in Brazil. This by-product (mainly calcium sulphate dihydrate) precipitates during... more
Phosphogypsum, a waste by-product derived from the wet process production of phosphoric acid, represents a serious problem facing the phosphate industry in Brazil. This by-product (mainly calcium sulphate dihydrate) precipitates during the reaction of sulphuric acid with phosphate rock and is stored at a rate of about 4x10(6) kg per day on several piles in Cubatão, Brazil. Contents of natural radionuclides from thorium and uranium series were measured in Brazilian phosphogypsum samples from disposal piles, using high-resolution gamma ray spectrometry and instrumental neutron activation analysis (NAA). These phosphogypsum piles present a potential threat to the surrounding environment and to the individual occupationally exposed. The results obtained in this study show that radionuclides, although present in relatively high concentrations in phosphogypsum, do not imply in significant doses for individuals occupationally exposed. The results obtained for the water activity in the monitor wells showed that the run-off of the piles is influenced by the activity present in the piles, giving indication of a possible groundwater contamination. Sediments from rivers in the area of influence of the pile presented higher concentrations of 238U and 232Th when compared with reference values.