Avaliação da toxicidade aguda do lixiviado tratado pelos processos de wetland e nanofiltração.

Abstract

In Brazil, treatment of leachate from the disposal of municipal solid waste is still a challenge, since there is currently no evidence of viable treatment that meets the discharge standards of the Brazilian legislation. In addition, the various types of waste, even when treated, have residual levels of substances that can confer toxicity to them. Because of this, there is a concern with these remaining substances, and especially, with its potential toxic possible. Given this situation, the incorporation of evaluation of toxicity in the treatment of effluents is of great importance in protecting aquatic environments. A growing interest in toxicity as a control parameter, which, however, is still largely unregulated. This study aims to increase knowledge about the treatment of leachate through the evaluation of toxicity by ecotoxicological tests. The acute toxicity of the leachate from the Metropolitan Landfill of Jardim Gramacho in Duque de Caxias was evaluated - RJ after treatment processes for wetland and nanofiltration using two test organisms of different trophic levels (Aliivibrio fischeri and Daphnia similis). The acute toxicity tests with Aliivibrio fischeri showed EC50 (%) values in the range from 11.75 to 96.17 to the tributary of the wetland and EC50 (%) values in the range from 21.60 to 86.32 for the effluent wetland. For both the affluent and effluent wetland values were obtained FT ≤ 8. For the effluent from the nanofiltration, the six acute toxicity tests with bacteria Aliivibrio fischeri, except for one sample, no toxicity was observed. For toxicity tests with Daphnia similis were obtained EC50 (%) values in the range from 24.15 to 70.71 for the affluent and wetland values ranging from 19.61 to 70.71 to the effluent of the wetland.