RITA DE CASSIA ANDRE DA SILVA

RITA DE CASSIA ANDRE DA SILVA

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Temporal trends (2006–2019) of metals and nonmetals in livers of great egrets (Ardea alba) from the São Paulo metropolitan region
2022 - SILVA, RITA C.A.; MOREIRA, EDSON G.; OLIVEIRA, PAULO T.M.S.; THEOPHILO, CAROLINA Y.S.; SILVA, PAULO S.C.; SANCHES, THAIS C.; COIMBRA, AMANDA A.; BIANCHI, TICIANA Z.D.; SAIKI, MITIKO
Temporal trends (2006–2019) of metals (Cd, Co, Cs, Cu, Fe, Hg, K, Mg, Mn, Na, Rb and Zn) and nonmetals (Br, Cl and Se) were assessed in livers of great egrets (Ardea alba) from São Paulo Metropolitan Region, Brazil. Male and female concentrations were compared and the relation between body mass and contaminant levels was evaluated as well as the risks of contaminant levels for the birds. Large variations were observed for toxic elements (Cd and Hg) over time. Some specimens presented toxic levels of Hg, Cu, Fe and Zn. Females presented lower concentrations of Br, Co, Cs, Rb, Se and Zn, while body mass and Zn were negatively correlated.
Monitoramento de elementos traço usando fígados da garça-branca-grande (Ardea alba) na Região Metropolitana de São Paulo, São Paulo, Brasil
2022 - SILVA, RITA de C.A.; SAIKI, MITIKO; MOREIRA, EDSON G.; OLIVEIRA, PAULO T.M.S.; THEOPHILO, CAROLINA Y.S.; SANCHES, THAIS C.; COIMBRA, AMANDA A.; BIANCHI, TICIANA Z.D.
O uso de bioindicadores no monitoramento da contaminação por elementos traço providencia evidências diretas da biodisponibilidade e do acúmulo de elementos tóxicos no ambiente e dispõe de recursos para avaliação ecológica que pode promover a conservação de espécies de aves. O fígado da garça-branca-grande (Ardea alba) pode ser considerado um bioindicador adequado para a avaliação da contaminação ambiental na Região Metropolitana de São Paulo (RMSP) porque a espécie é considerada residente na região e apresenta grande capacidade de bioacumulação de contaminantes, em virtude de ocupar o topo das cadeias alimentares aquáticas. O presente estudo vem sendo desenvolvido por meio de doações de animais adultos mortos pela Divisão de Fauna Silvestre da Prefeitura de São Paulo. O método da Análise de Ativação Neutrônica (AAN) possibilitou a determinação de treze elementos traço (Br, Cl, Co, Cs, Cu, Fe, K, Mg, Mn, Na, Rb, Se e Zn). Para tanto, foram realizadas irradiações sob diferentes fluxos de nêutrons térmicos e por diferentes períodos de tempo no reator nuclear de pesquisa IEA-R1 do IPEN-CNEN/SP. Os elementos tóxicos Cd e Hg foram determinados pelo Método de Espectrometria de Absorção Atômica (AAS). Os resultados obtidos indicaram concentrações médias elevadas de Cu, Hg, Fe e Zn e alguns espécimes apresentaram teores tóxicos destes elementos. A análise temporal no período de 2006 a 2013 também mostrou que os elementos Cu, Fe, Mn e Zn tiveram um leve aumento nos últimos anos. Em relação às diferenças entre os sexos das garças, as fêmeas apresentaram menores níveis de Br, Co, Cs, Rb, Se e Zn. Estes resultados confirmam que o monitoramento com fígados da garça-branca-grande é uma excelente ferramenta para o controle da contaminação por elementos traço na RMSP além de fornecer dados ecotoxicológicos que podem contribuir para a conservação da avifauna local.
Trace elements in livers of great egrets (Ardea Alba) from São Paulo metropolitan region
2019 - SILVA, RITA de C.A. da; SAIKI, MITIKO; MOREIRA, EDSON G.; OLIVEIRA, PAULO T.M.S.; THEOPHILO, CAROLINA Y.S.; SANCHES, THAIS C.; COIMBRA, AMANDA A.; BIANCHI, TICIANA Z.D.
To evaluate possible variations over time (2006-2013) in trace element levels in livers from adult specimens of great egret from the São Paulo Metropolitan Region (SPMR), recent data and published data have been used. The elements Br, Cl, Co, Cs, Cu, Fe, K, Mg, Mn, Na, Rb, Se and Zn were determined by Neutron Activation Analysis (NAA) and the toxic elements Cd and Hg by Atomic Absorption Spectrometry (AAS). The large inter annual variations observed for several elements showed the importance of expanding the time period for this analysis as the series is considered short (<10 years). However, non-significant increase of Br, Cu, Mn, Fe and Zn and a decrease in Cd, also non- significant, were observed at the end of the series. The concentration relations with sex and mass of the birds were also assessed. Females presented lower concentrations of Br, Co, Cs, Se and Zn and it may be related to metabolic differences, detoxification pathways, and other factors. No relationship between body mass and element levels were observed. Obtained results demonstrated the importance of temporal monitoring of trace elements in livers of great egrets, especially for the results obtained for Cu, Fe and Zn, since the contamination by these elements in the region should be considered. The present study is the first relating contaminant level with conditions of birds in the region, encouraging future studies that evaluate this issue.
The great egret (Ardea alba) as a bioindicator of trace element contamination in the São Paulo Metropolitan Region, Brazil
2018 - SILVA, RITA C.A.; SAIKI, MITIKO; MOREIRA, EDSON G.; OLIVEIRA, PAULO T.M.S.
To investigate great egret as a possible bioindicator of trace element contamination, the concentrations of Br, Cd, Co, Cs, Cu, Fe, Hg, K, Mg, Mn, Na, Rb, Se and Zn were determined in livers of great egrets (Ardea alba) by the methods of Instrumental Neutron Activation Analysis and Atomic Absorption Spectrometry. It was observed that the levels of trace elements found in their livers may indicate contamination of the studied region. Thus, the livers of this species can be considered as a suitable bioindicator of contamination of the aquatic systems in the So Paulo Metropolitan Region.
A study on trace element contamination in the metropolitan region of São Paulo (São Paulo, Brazil), using the livers of great egret (Ardea alba) as a biondicator
2017 - SILVA, R.C.A.; SAIKI, M.; MOREIRA, E.G.; MEIRA, P.T.; OLIVEIRA, S.
Herons and egrets are considered bioindicators suitable for the assessment of environmental contamination, since they occupy the top of the food chain, and tend to accumulate high concentrations of toxic elements in their tissues. So, in this study the livers of the great egret (Ardea alba) were used as a bioindicators of changes in trace element concentrations between 2006 and 2011 (6 years) in the aquatic environments of the Metropolitan Region of São Paulo (SPMR). The levels of trace elements found in livers of males and females were also compared. The method of Neutron Activation Analysis (NAA) was used in these analyses for the determination of Br, Co, Cs, Fe, K, Mg, Mn, Na, Rb, Se and Zn, and Atomic Absorption Spectrometry Method (AAS) for the determination of Cd and Hg in liver samples. In previous studies, elevated concentrations of trace elements such as Cu, Fe, Hg, Mn and Zn were found in livers. In addition to the previous published data, the results for six trace elements (Co, Cs, Fe, Rb, Se and Zn) of five liver samples collected during 2011 were included. The concentrations of Br, Co, Fe, K, Mg, Na and Se found in livers in 2011 remained at similar levels to those obtained in 2006. However, increase in levels of Cd, Cu, Hg, Mn and Zn in 2011 was obtained, probably related to an increase in environmental depositions from anthropogenic sources. Female egrets presented lower levels of Co, Cs, Se and Zn than males. Selenium requires great attention due the differences indicating possible transference to the eggs and Se can be toxic for embryos. Results obtained in this study suggests a continuous monitoring using great egret livers in order to improve the knowledge of temporal trends of contamination in aquatic environments of the SPMR.
Trace elements in livers of great egret (Ardea alba) from the São Paulo metropolitan region: a preliminary assessment of temporal trends
2015 - SILVA, RITA de C.A.; SAIKI, MITIKO; MOREIRA, EDSON G.; OLIVEIRA, PAULO T.M.S.
Concentration of trace elements in livers of the creat egret (Ardea alba) from the metropolitan region of São Paulo, SP, Brazil
2011 - SILVA, RITA de C.A.; SAIKI, MITIKO
Determinacao de elementos traco em figados da carca-branca-grande (Ardea alba) da regiao metropolitana de Sao Paulo
2010 - SILVA, R. de C.A.; SAIKI, M.
Assessment of environmental trace element contamination in the São Paulo Metropolitan Region, Brazil, using the liver of the Great White heron ( ARDEA ALBA LINNAEUS( 1758)) as bioindicator
2012 - SILVA, RITA de C.A.; SAIKI, MITIKO; MOREIRA, EDSON G.; OLIVEIRA, PAULO T.M. e S.
Selenium levels in liver of great egret (ardea alba) from São Paulo metropolitan regions, Brazil
2011 - SILVA, RITA de C.A.; SAIKI, MITIKO; OLIVEIRA, PAULO T.M.S.