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