Rio Santa Maria da Vitória (ES, Brasil): avaliações ecofisiológicas e toxicogenéticas em amostras de água, sedimento e elutriato do sedimento
Nenhuma Miniatura disponível
Data
2017-12-18
Autores
Duarte, Ian Drumond
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Federal do Espírito Santo
Resumo
The Santa Maria da Vitória River (ES, Brazil) is ecologically and socioeconomically important, but it suffers from several anthropic impacts. Considering its importance, this work analyzed water, sediment and sediment elutriate quality of this river on two periods on six sampling stations, through quantification of metals and ecotoxicological responses in cells of Allium cepa L., Lactuca sativa L. and culture of CHO-K1 cells. Metals quantification in samples was based on the U.S. EPA 200.8 method, being sediment prepared by the U.S. EPA 3051 method. From water samples, toxigenic assays were carried out in A. cepa and L. sativa by means of root meristematic and F1 cells. Thus, mitotic index, chromosomal aberration rate and micronucleus frequency were calculated to evaluate, respectively, cytotoxicity, genotoxicity and mutagenicity. From CHOK1 lineage cell culture, cytotoxic potential of samples was evaluated through MTT, Tripan blue and nuclear division index tests. Genotoxic potential was evaluated by comet assay, while the mutagen, by micronucleus test with cytokinesis block. In experiments with L. sativa, phytotoxicity analyzes were carried out, and in pregrowth stage, activities of antioxidant enzymes superoxide dismutase, catalase, ascorbate peroxidase and guaiacol peroxidase were analyzed, as well as estimated chlorophyll content. In addition, gaseous exchanges were analyzed from the CO2 net assimilation, stomatal conductance, intracellular CO2 concentration, transpiration, intra- and extracellular CO2 concentration ratio and carboxylation efficiency. Sediment and sediment elutriate samples were evaluated by toxicogenic assays in A. cepa. Among quantified metals, Mn, Pb, Cu and mainly Al showed the highest concentrations, being suggested as the major contaminant evaluated. In this sense, it is suggested that metals concentration is related to geomorphological and pedological characteristics of the region, as well as to anthropic sources. These metals concentrations could be influenced by precipitation and flow of Santa Maria da Vitória River. The variables analysed by A. cepa, L. sativa and CHO-K1, revealed cytotoxic and genotoxic potentials in both water, sediment and elutriate of sediment samples. Besides that, water samples showed phytotoxic potential in L. sativa, and promoted an increase in antioxidant metabolism in some stations. The gas exchange analysis showed a decrease in photosynthetic process efficiency, possibly related to Cu concentrations. The effects observed in this study can be related to quantified metals on evaluated samples. Therefore, considering evaluated variables, it is concluded that Rio Santa Maria da Vitória environmental quality is compromised.
Descrição
Palavras-chave
Antioxidant metabolism , Gaseous exchanges , Metais , Metals , Trocas gasosas , Allium cepa , CHO-K1 , Lactuca sativa
Citação
DUARTE, Ian Drumond. Rio Santa Maria da Vitória (ES, Brasil): avaliações ecofisiológicas e toxicogenéticas em amostras de água, sedimento e elutriato do sedimento. 2017. 181 f. Tese (Doutorado em Biologia Vegetal) - Universidade Federal do Espírito Santo, Centro de Ciências Humanas e Naturais, Vitória, 2017.