An Investigation for of the toxicity of some textile dyes on amphibian tadpoles

ABSTRACT Master Thesis AN INVESTIGATION FOR THE TOXICITY OF SOME TEXTILES DYES ON AMPHIBIAN TADPOLES Ufuk Günay DO?AN Inonu University Graduate School of Natural and Applied Sciences Department of Biology 49+vii pages 2002 Supervisor: Assoc. Prof. Dr. Murat ÖZMEN Astrazone dyes, among many others, are one of the commonly used group of synthetic substances in the textile industry. Several textile dyes and their effluents were found to be toxic, genotoxic and mutagenic in various test organisms. However, to our knowledge, the information related to the toxicity of astrazone dyes on aquatic organizms is limited. This study presents the toxicity of four different astrazon dyes on Bufo viridis (frog of land) tadpoles. The toxic effect was investigated in two different developmental stages of the tadpoles in static, renewal test conditions. LC50s were determined as 2.89 ppm, 4.00 ppm, 39.35 ppm and 66.03 ppm for astazon blue, black, yellow and red dyes, respectively, in the 20th stages of development in 72 h of exposure period. The LC50 values were also found as 0.919 ppm, 2.66 ppm, 20.37 ppm and 13.69 ppm in 24th stage of the developmental period in 72 h of exposure under the same conditions for the same dyes. Non Observed Effective Concentration (NOEC) and Lowest Observed Effective Concentration (LOEC) values were also determined in two different developmental stages of tadpoles using analysis of variance (ANOVA) test. The NOEC-LOEC values were found to be as 2.57-2.82 ppm, 3.38-3.68 ppm, 39.52-41.92 ppm and 65.42-69.40 ppm for astrazon blue, black, yellow and red dyes, respectively, on 20lh developmental stages of tadpoles after 72 h treatment period. Also, these values were found to be as 1.36-1.63 ppm, 2.35-2.58 ppm, 13.15-18.92 ppm and 9.46-13.23 ppm for same dyes at the 24th developmental stages after same treatment period. Glutathion S-transferase (GST) and carboxylesterase (CaE) activities were also determined B.viridis tadpoles after 12 and 24 h treatment period. Enzymatical activities were increased, significantly, after some exposure concentrations of dye substances in 24th stages of tadpoles. These results show that, astrazon blue is the most toxic textile dye to tadpoles in 20lh and 24th stages of the development. Finally, the 24th stage of tadpoles were determined to be more sensitive than 20th stage ones for all dyes tested in various concentrations. KEY WORDS: Astrazon, textile dye, toxicity, tadpole, Bufo viridis, lethal concentration, NOEC, LOEC, GST, CaE