Ecotoxicological evaluation of Glyphosate use in controlling E. crassipes e Salvinia sp. macrophytes

The present work aimed to carry out traditional ecotoxicological and ecosystemic tests in microcosms for the evaluation of the use of glyphosate herbicide adopted to control floating aquatic macrophytes in aquatic ecosystems. Ecotoxicity tests were performed using standardized methodology and standard species of different trophic levels. Although the active ingredient glyphosate is toxic, the toxicity of its commercial formulation is higher. The inert ingredient of the Roundup Original® composition may be responsible for the higher commercial compound toxicity. Experiments in microcosms indicated that the use of the formulation is possible, in considering tested concentration and controlling the spray process, without causing toxic effect on the aquatic ecosystem. Complementary studies evidenced the risk of using the product in aquatic environments without vegetation cover, being not recommended the herbicide application in a place without floating aquatic macrophytes cover.