Abstract: Acute toxicity of nitrobenzene exposure to three representative native organisms,i.e.Rana chensinensis tadpoles,Cipangopaludina cahayensis and Macrobrachium nipponense,was studied using the static-renewal method.Based on the USEPA Trimmed Spearman-Karver(TSK) method,ρ(96 h,LC₅₀) of nitrobenzene for Rana chensinensis tadpoles was determined to be 117.04 mg·L^-1;for Cipangopaludina cahayensis,104.23 mg·L^-1 and for Macrobrachium nipponense,0.033 7 mg·L^-1.Based on the ρ(96 h,LC₅₀) values obtained,with the safety factor set as 0.01,the safe concentration(ρ_s) of nitrobenzene in surface water was 1.17 mg·L^-1 for Rana chensinensis tadpoles;1.04 mg·L^-1 for Cipangopaludina cahayensis,and 0.34 μg·L^-1 for Macrobrachium nipponense.The sensitivity of the 3 subjects to toxicity of nitrobenzene was in the order of Macrobrachium nipponense≥Cipangopaludina cahayensis>Rana chensinensis tadpoles.According to the criteria of acute toxicity classification for fish acute toxicity tests,nitrobenzene was extremely toxic to Macrobrachium nipponense,and moderately toxic to Cipangopaludina cahayensis and Rana chensinensis tadpoles.This study provides some relevant data for maintaining normal growth and reproduction of aquatic life in China and for setting up benchmark for nitrobenzene in waterbodies for aquatic life.

Key words: nitrobenzene, Rana chensinensis tadpole, Cipangopaludina cahayensi, Macrobrachium nipponense, acute toxicity