Avaliação toxicológica do xenobiótico metabissulfito de sódio na sobrevivência do caranguejo-violinista Minuca mordax (Smith, 1870) (Decapoda, Ocypodidae)

The aim of this study was to assess the toxicological risk of sodium metabisulphite through the lethal concentration (Cl 50-96h) in Minuca modax. The crabs were subjected to an experiment using a completely causalized experiment design, with five concentrations of sodium metabisulphite (0,0; 0,05; 0,07; 0,10 and 0,15 mg/L) and five replicates each. The experiment was conducted in a static system, using a container with 2L of water, with a stocking density of two adult crabs each, lasting 96 hours. With sodium metabisulphite, survival rates of 0% were observed in the first 12 hours of exposure at a concentration of 0,15 mg/L. At the end of the experiment, the following survival rates were obtained in ascending order of exposure: 100, 90, 90, 40 e 0%. Cl 50-96h is estimated to be 0.10 mg/L. Thus, this study leads to the conclusion that the fiddler crab is sensitive to sodium metabisulphite, with concentrations above 0,10 mg/L capable of causing mortality in the cultivation of this specie.