Ecotoxicity of Sludges Generated by Textile Industries: a Review

Abstract

Textile industries consume a large amount of water and use toxic products in its processes. Consequently, they produce and release large volumes of effluents, which, treated, generate great amount of sludge. The final disposal of this sludge remains a challenge, and its ecotoxicological assessment is an important parameter to minimize its impacts. This article reviewed the ecotoxicological tests that have been employed to evaluate the hazard of such sludge. There are few papers in the literature on this issue, as well as a lack of consensus about sample preparation procedures and test organisms to be used. The test organisms most employed are higher plants, bacteria and aquatic organisms. Only one article used earthworms and one, mammals. Composting was efficient for reduction or elimination of the phytotoxicity of textile sludge. Both Daphnia magna and Vibrio fischeri showed adequate sensitivity for sludge acute toxicity evaluation. The endpoint genotoxicity using the Salmonella/ microsome assay seems to be important, because most of the obtained results were positive. More studies are needed to understand the applicability of algae, earthworms and mammals. Efforts are being made to establish a reliable battery of bioassays for ecotoxicological evaluation of such waste.

Pollution indices and biotests as useful tools for the evaluation of the degree of soil contamination by trace elements

“…Also, some studies have shown that germination is relatively little affected by the presence of contaminants in the soil (Baran and Antonkiewicz 2017). Many plants germinate in a contaminated environment but later stop growing; therefore, the root growth parameter is more sensitive and useful in assessing the ecotoxicity of different samples Ali et al 2004;Gomes et al 2012). Roots are the first part of the plant exposed to toxic substances that inhibit root growth, which is associated with a decrease in cell mitotic activity (Fusconi 2006).…”

Fitotoxicidade e citogenotoxicidade da água e sedimento de córrego urbano em bioensaio com Lactuca sativa

“…Esses efluentes estão associados à presença de metais e a outras substâncias nocivas provenientes dos produtos químicos empregados nos seus processos e que podem ser encontrados nos corpos d'água que os recebem. Tem crescido o número de estudos ecotoxicológicos sobre corantes têxteis devido à sua toxicidade, além da toxicidade dos seus produtos de degradação biótica e abiótica (Gomes et al, 2012).…”

Avaliação da toxicidade das águas do Rio Criciúma (Criciúma, Santa Catarina, Brasil), utilizando parâmetros físico-químicos e abordagens ecotoxicológicas

“…Além da avaliação de parâmetros físico-químicos, é também relevante a utilização de ensaios ecotoxicológicos em organismos bioindicadores, como forma de se obter melhor avaliação da qualidade de mananciais hídricos contaminados (Tallini et al, 2012;Gomes et al, 2012). Neste contexto, tem sido proposto o uso de teste de toxicidade aguda em Daphnia spp pela avaliação do Fator de Toxicidade (FT).…”