Toxicity evaluation of Vitrofural® residues in agar on earthworms

Abstract

Vitrofural® is an additive used for the chemical sterilization of plant culture media in the in vitro propagation of plants. At the end of its use, it becomes a waste of the biotechnological process and is dumped into confined terrestrial environments. Nevertheless, the possible ecotoxicological impacts that could occur are unknown. The aim of this work was to determine the acute toxicity of earthworms (Eisenia foetida) by exposure to Vitrofural® residues on agar. The toxic potential of the waste was evaluated by single exposure to earthworms for 14 days. Worms were exposed by contact and ingestion at a concentration corresponding to the maximum possible to be obtained from lixiviate of the solid residue of Vitrofural® on agar, after 7 and 21 days of preparation. The number of dead animals and the loss of body mass were quantified, and the sublethal toxic signs were described. In the experimental groups there was no mortality, only slight morphological and physiological alterations were observed with a tendency to decrease in frequency in the group exposed to the lixiviates with 21 days of preparation. Similar response was observed in the evolution of body mass. The lixiviated of Vitrofural® in agarized medium induce slight sublethal effects in earthworms a function of the preparation time and demonstrate the absence of ecotoxicological risk due to exposure in this specie. Keywords: bioassay, chemical sterilization, Eisenia foetida, toxicity