TURKISH JOURNAL OF FISHERIES AND AQUATIC SCIENCES

Aquatic toxicity of municipal wastewater was evaluated in an acute toxicity test using water flea, Daphnia magna as an freshwater aquatic experimental animal model. Toxicity test were performed on samples of both untreated (raw) and treated wastewaters were collected Manisa municipal effluents. Undiluted untread and treated effluents were very toxic to D. magnaand cause to death of all exposed daphnids. Dilution of wastewaters was observed to decrease percentage of influence of biological toxicity based on dilutional rate. Acute toxic effect of untreated wastewater on D. magnawas more than that of treated wastewater. In addition, the longer the period of exposure to D. magna, the more significantly toxic effect increased