Phytoremediation processes of domestic and textile effluents: evaluation of the efficacy and toxicological effects in Lemna minor and Daphnia magna

DE ALKIMIN, GILBERTO DIAS; PAISIO, CINTIA; AGOSTINI, ELIZABETH; NUNES, BRUNO

ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH

SPRINGER HEIDELBERG

Año: 2019 vol. 27 p. 4423 - 4441

0944-1344

Phytoremediation has been proposed as a potential biotechnological strategy to remediate effluents before their release into the environment. The use of common aquatic plant species, such as macrophytes (e.g., Lemna spp.) as a cleanup solution has been proposed decadesago. However, the effectiveness of such processes must be assessed by analyzing the toxicity of resulting effluents, for the monitoring ofwastewater quality. To attain this purpose, this work intended to quantify the efficacy of a Lemna-based wastewater phytoremediationprocess, by analyzing toxicological effects of domestic and textile effluents. The toxic effects were measured in Lemna minor (sameorganisms used in the phytoremediation process, by quantifying toxicological endpoints such as root length, pigment content, and catalaseactivity) and by quantifying individual parameters of Daphnia magna (immobilization, reproduction, and behavior analysis).Phytoremediation process resulted in a decrease of chemical oxygen demand in both effluents and in an increase in root length of exposedplants. Moreover, textile effluent decreased pigments content and increased catalase activity, while domestic effluent increased theanthocyanin content of exposed plants. D. magna acute tests allowed calculating a EC50 and Toxic Units interval of 53.82?66.89%/1.85?1.49, respectively, to raw textile effluent; however, it was not possible to calculate these parameters for raw and treated domesticeffluent (RDE and TDE). Therefore, in general, the acute toxicity of effluent toward D. magna was null for RDE, and mild for the treatedtextile effluent (TTE), probably due to the effect of phytoremediation. Exposure to textile effluents (raw and treated) increased the totalnumber of neonates of D. magna and, in general, both textile effluents decreased D. magna distance swim. Moreover, although botheffluents were capable of causing morphological and physiological/biochemical alterations in L. minor plants, organisms of this specieswere able to survive in the presence of both effluents and to remediate them.