Reginaldo Geremias

MICROESFERAS DE QUITOSANA RETICULADAS COM TRIPOLIFOSFATO UTILIZADAS PARA REMOÇÃO DA ACIDEZ, FERRO(III) E MANGANÊS(II) DE ÁGUAS CONTAMINADAS PELA MINERAÇÃO DE CARVÃO

Considerable attention has been paid to chitosan and derivatives as efficient adsorbents of pollutants such as metal ions and dyes in aqueous medium. Nevertheless, no report can be found on the remedial actions of chitosan microspheres crosslinked with tripolyphosphate to control acidity, iron (III) and manganese (II) contents in wastewaters from coal mining. In this work, chitosan microspheres crosslinked with tripolyphosphate were used for the neutralization of acidity and removal of Fe (III) and Mn (II) from coal mining wastewaters. The study involved static and dinamic methods. The neutralization capacity of the surface of the static system was 395 mmol of H3O+ per kilogram of microspheres, higher than that of the dynamic one (223 mmol kg-1). The removal of Fe(III) in wastewater was of 100% and that of Mn(II) was 90%.

Antihyperlipidemic effect of Casearia sylvestris methanolic extract

Casearia sylvestris methanolic extract (MCE) was screened at doses of 125-500 mg/kg for its antihyperlipidemic activity. The antihyperlipidemic effect was evaluated in olive oil-loaded mice. Acute treatment caused inhibition in the triglyceride (TG) and serum lipase elevation-induced by 5 ml/kg of olive oil.

Bioaccumulation and toxic effects of copper in common onion Allium cepa L.

The aim of this study was to investigate the potential utility of Allium cepa L. as a bioindicator organism for measuring copper bioaccumulation and toxicity in laboratory conditions. Onions were exposed to increasing concentrations of the metal (0, 0.1, 0.5, 1, 5 and 10 μg mL−1) for 7 days. Root and leaf development were chosen as biological endpoints, while bioaccumulation was evaluated in roots, bulbs and leaves. Copper caused inhibition of root elongation with increasing effects at the higher doses, growth being reduced by almost 60% at 0.1 μg mL−1 and up to 95% at 10 μg mL−1. The elongation of leaves was significantly lower only in specimens exposed at 0.5 μg mL−1, but a total absence of newly formed tissues was observed at 10 μg mL−1. A marked bioaccumulation of copper was measured in roots, with values increasing up to almost four orders of magnitude compared to controls; only slight or even no significant differences were observed for copper levels in leaves and bulbs of treated A. cepa. Multiple linear correlations revealed a significant inverse relationship between copper concentrations and tissue length in both the roots and leaves, evidencing a sensitive responsiveness of this biological model. The overall results suggest the suitability of A. cepa as a robust species for easy and simple ecotoxicological bioassays to test the toxic effects and bioavailability of environmental pollutants, especially trace metals.

ESTUDO DA QUALIDADE DAS ÁGUAS DO RIO MAROMBAS (SC/BRASIL), UTILIZANDO PARÂMETROS FÍSICO-QUÍMICOS E BIOENSAIOS.

O presente trabalho propos realizar estudos preliminares de avaliacao da qualidade das aguas do Rio Marombas (SC-Brasil), utilizando parâmetros fisico-quimicos e bioensaios. Amostras de aguas do Rio Marombas foram coletadas em 3 pontos e realizada a determinacao de pH, oxigenio dissolvido (OD), analise de agroquimicos, hidrocarbonetos policiclicos aromaticos (HPA’s), compostos orgânicos volateis (COV’s) e bifenilas policloradas (PCB’s). Foram executados ensaios de toxicidade aguda (CL50) em microcrustaceos Artemia sp. e de fitotoxicidade em Allium cepa L. avaliada pela inibicao de crescimento e peso de raizes e pelos biomarcadores de estresse oxidativo glutationa reduzida (GSH) e peroxidacao lipidica. Os resultados dos parâmetros fisico-quimicos indicaram que os valores de pH estiveram compativeis com padroes previstos pela legislacao. Foi constatada a presenca dos agroquimicos metomil nos Pontos 1 e 2 e metconazol no Ponto 1. Os bioensaios revelaram que nao houve toxicidade em Artemia sp. e ausencia de inibicao de crescimento e peso de raizes em Allium cepa L. A concentracao de GSH estava significativamente aumentada no Ponto 3 quando comparada ao Ponto 1 e ao controle negativo. Nao foi observada diferenca significativa na avaliacao de peroxidacao lipidica entre os diferentes grupos. Esses resultados indicam que as aguas do Rio Marombas podem estar sendo contaminadas por agroquimicos, sugerindo a necessidade de implementacao de sistema de monitoramento periodico de sua qualidade. Palavras-chave : rio Marombas; parâmetros fisico-quimicos; bioensaios STUDY OF WATER QUALITY FROM THE MAROMBAS RIVER (SC/BRAZIL) USING THE PHYSICOCHEMICAL PARAMETERS AND BIOASSAYS . ABSTRACT The present study proposed preliminary studies assessing the quality of water from the river Marombas (SCBrazil) using the physicochemical parameters and bioassays. Samples of water from Marombas river were collected at three points and it was determined the pH, dissolved oxygen (DO), concentration of agrochemicals, polycyclic aromatic hydrocarbons (PAH’s), volatile organic compounds (VOC`s) and polychlorinated biphenyls (PCB´s). Acute toxicity tests (LC50) were carried out in microcrustaceans Artemia sp. and phytotoxicity tests in Allium cepa L. assessed through the inhibition of growth and weight of roots and by biomarkers of oxidative stress reduced glutathione (GSH) and lipid peroxidation. The results of physicochemical parameters indicated that the pH values were consistent with standards established by the legislation. It could be observed the presence of the agrochemicals methomyl in Points 1 and 2 and metconazole in Point 1. The bioassays showed absence of the acute toxicity in Artemia sp. and there was no inhibition of growth and weight of roots in Allium cepa L. The concentration of GSH was significantly increased (P<0.05) in Point 3 when compared to Point 1 and the negative control. No significant difference could be observed in the evaluation of lipid peroxidation between different groups. These results demonstrate that the water of the Marombas river is contaminated by agrochemicals, suggesting the necessity of implementing a system of monitoring its quality. Key words : Marombas river, physicochemical parameters, bioassays

EVALUATION OF ACID MINE DRAINAGE TREATMENT USING Artemia sp. AND Allium cepa AS BIOINDICATORS OF TOXICITY AND GENOTOXICITY 1 .

Coal mining produces residues containing high levels of heavy metals and other components that contaminate surface and ground water. This research evaluated the efficiency of physical, chemical, and biological treatment of acid mine drainage using alternative biological indicators Artemia sp. (brine shrimp) and Allium cepa L. (onion). Samples were collected at four stations that are located at specific treatment system: 1) pH control and precipitation, 2) biological damping pond outlet, 3) wetland inlet, and 4) wetland outlet. Acute toxicity analysis using Artemia sp. was performed at sample concentrations of 25, 50, 80, 90, and 100%. Toxicity in A. cepa was observed as root growth inhibition after a seven-day exposure period at 100% effluent concentration. Genotoxicity was observed in A. cepa meristematic cells using the comet assay that evaluates DNA strand breaks in single cells. Artemia sp. test results indicated a reduction of lethality in station 4 (less than 30%) when compared to station 3 (100%), indicating that the wetland is effective at reducing residue toxicity for these organisms. The high lethality at Station 3 was investigated and resulted in the discovery that contaminated ground water from residue leachate was entering the treatment system between Stations 2 and 3. Root growth inhibition showed no significant results, indicating that the effluent has no activity to A. cepa considering this parameter. The comet assay results indicate that stations 1 and 2 are genotoxic and a significant reduction can be observed after the biological processes, particularly at the wetland output. Thus, the results obtained indicate that Artemia sp. is a suitable bioindicator for toxicity assays of this effluent and that A. cepa is only suitable for evaluating genotoxicity. We can also observe that the treatment process is efficient at eliminating effluent toxicity and reducing genotoxicity.

UTILIZAÇÃO DE REJEITO CARBONOSO CALCINADO PARA O TRATAMENTO DE ÁGUAS ATINGIDAS POR CONTAMINANTES DA MINERAÇÃO DO CARVÃO.

The coal industry is one of the main economic activities in southern of Santa Catarina, Brazil. However, generates carbonous waste not recovered economically, which could contaminate water sources, including the Urussanga River. This study aimed to use of the calcinated carbonous waste for the treatment of waters contaminated by waste from coal mining. The samples water from Urussanga River and carbonous waste were collected. The waste was subjected to calcination to obtain metal oxides. The waters of the river were treated with calcinated carbonous waste in batch system. Before and after treatment were determined the concentrations of metal ions Al (III), Fe (III) and Mn (II) and the pH. Was performed acute toxicity tests on Daphnia magna and Artemia sp. exposed to different dilutions of untreated and treated water and determined the median lethal concentration (LC 50 ) for Artemia sp. and Dilution Factor (DF) to Daphnia magna . Phytotoxicity test was conducted in Allium cepa L. exposed to untreated and treated water, and evaluated the inhibition of root growth. The results indicated that the treatment increased the pH as well as it promoted an expressive removal of metal ions. It was observed that after treatment there was no mortality in Artemia sp. and it was found to reduce the toxicity to Daphnia magna and normal growth of roots in Allium cepa L. In conclusion, the use of the calcinated carbonous waste could be considered as an alternative for the treatment of waters affected by contaminants from coal mining.