Toxicity of treated printing and dyeing effluents on several juvenile marine animals

Abstract:

To accurately evaluate the comprehensive toxicity of treated printing and dyeing effluents, the 96-hour acute toxicity tests were conducted with juvenile Exopalaemon carinicauda, Portunus trituberculatus, Cynoglossus semilaevis, Mugil cephalus, Sinonovacula constricta, and Bullacta exarata, and the toxicity unit classification system and potential ecotoxic effects probe(PEEP) were used to evaluate the biological toxicity of treated printing and dyeing effluents. The results showed that the major physical and chemical characteristics of treated printing and dyeing effluents conform to the standards of “Discharge standards of water pollutants for dyeing and finishing of textile industry” and “Integrated effluents discharge standard” except aniline, but the content of aniline was very low. The 96-hour acute toxicity tests showed that the sequence of acute toxicity level was C. semilaevis >E. carinicauda >M. cephalus >P. trituberculatus >S. constricta >B. exarata, and the treated printing and dyeing effluent was classified as moderate toxicity grade with the value of 4.16 by toxicity unit classification system, meanwhile, the value of PEEP was 4.72, being classified as highly toxic grade. The biological monitoring methods can be used to estimate synthetic toxicity of treated printing and dyeing effluents completely.