Quantificação e avaliação da biodisponibilidade de metais em sedimentos na Baía da Ribeira RJ

• Ano de defesa: 2014
• Autor(a) principal: Chiappetta, Janine de Moraes Mariano
• Orientador(a): Lessa, Josane Alves
• Banca de defesa: Maria, Luiz Cláudio de Santa , Machado, Wilson Tadeu Valle
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade do Estado do Rio de Janeiro
• Programa de Pós-Graduação: Programa de Pós-Graduação em Química
• Departamento: Centro de Tecnologia e Ciências::Instituto de Química
• País: BR
• Palavras-chave em Português: Dosagem de metais; sedimentos; método AVS/SEM; Baía da Ribeira.
• Palavras-chave em Inglês: Dosing of metals; sediments; method AVS/SEM; Ribeira Bay
• Área do conhecimento CNPq: CNPQ::CIENCIAS EXATAS E DA TERRA::QUIMICA
• Link de acesso: http://www.bdtd.uerj.br/handle/1/15777

The toxicity of metals in aquatic environments is related to their bioavailability, and this can be influenced by several factors. The sediment characteristics make it an important compartment for assessment of the level of contamination in the aquatic environment. This study aimed to quantify and assess the bioavailability of metals in sediments from the Ribeira Bay. In this region, are the most populous districts of Angra dos Reis - RJ. This bay is located in the northeast part of the Ilha Grande Bay, which consists of a fishery, tourist space and important economic and industrial value. 12 sediments were collected in the Ribeira Bay and determined the levels of the metals Al, Cu, Cd, Cr, Fe, Mn, Ni, Pb and Zn by aqua regia extraction protocol (BCR -701) and the potential toxicity of metals Cd, Cu , Ni , Pb and Zn by extraction of Acid Volatile Sulfide and Simultaneously Extracted Metal (AVS/SEM). Measurements of pH, redox potential (Eh), organic carbon , total phosphorus and particle size were also made. Through these data it was possible to study correlations between these variables. The concentrations of each metal are similar in the different locations of sediment and no significant differences with compared to published studies in the area. The values of ΣSEM/AVS (0.02 to 0.2) smaller than 1 indicate that there is amount of sulfides sufficient for trapping of the metals investigated. The correlations obtained by Principal Components Analysis show a direct relationship between the concentrations of most metals extracted by aqua regia (Ni, Fe, Cr, Cu, Zn); between the metals Mn, Pb, Al and total phosphorus; between organic matter content, total organic carbon, total phosphorus with the fractions fine silt and clay and the Eh. The results suggest that the region no suffer significant influence of anthropogenic sources in relation to metals and, according to the AVS/SEM, these are not readily available to the environment and therefore have low toxic potential