A Escolha do Anfípodo Bentônico para Ensaios Ecotoxicológicos com Sedimentos Marinhos

The Choice of Benthic Amphipod for Ecotoxicological Tests with Marine Sediments Recently, the ABNT-NBR 15638 standard was published normalizing the method of ecotoxicological test with whole sediment using the benthic amphipods Leptocheirus plumulosus and Tiburonella viscana. These test organisms are the most widely used for this matrix in studies of Brazilian marine and estuarine environments. In order to analyse some experimental conditions in toxicity tests with these two amphipods, data from a monitoring program conducted in the oceanic region of Santos-SP were compiled. The results of ecotoxicological tests with Leptocheirus plumulosus and Tiburonella viscana indicated that sediments in the region have low contamination levels. The precision within replicates used in the tests showed that the coefficient of variation was similar (CV = 22%) for both amphipods, however, there was a weak explanation with the intensity of the toxic effect in the Tiburonella viscana test. Regression analysis indicated significant correlation among the intensity of the toxic effect to Tiburonella viscana and the concentration of N-Kjeldahl, and also the proportion of silt+clay in sediments, which did not occur to Leptocheirus plumulosus. Based on present study and others, it was possible to estimate that survival of Tiburonella viscana is affected in sediments with low levels of contamination, but more than 33% of silt+clay (fines).