Toxicity of Trichlorfon Against Carassais auratus gibebio and Its Impacting Factors

In this experiment,toxicity of trichlorfon and its impacting factors against Carassais auratus gibebio were studied.Using the method of linear-interpolation,acute toxicity test of trichlorfon to Carassais auratus gibebio was established in static water with different times and its impacting factors of trichlorfon toxicity was determined with mortality of Carassais auratus gibebio.The results showed the 48 h,72 h and 96 h LC50(median lethal concentration) values for trichlorfon against fingerling of Carassais auratus gibebio(1.0 g±0.3 g BW)were found to be 121.19、90.22、59.78 mg·L-1,respectively,and deriving the safety concentration(SC)was 5.98 mg·L-1.The LC50 value of larval development of Carassais auratus gibebio(23.2 g±3.6 g,BW)for 48 h was 411.65 mg·L-1.The toxicity of trichlorfon was stronger with enhancement of either water pH value or temperature and showed no effects on the fishes when the pH was below 6.In conclusion,trichlorfon had a low toxicity against the studied fish when trichlorfon concentration was in the safety range and at pH at 6～8,with temperature below 26 ℃.