Abstract: The toxicity of CEH bleaching effluents was studied with photobacteria. The toxicity of C stage was the strongest, its EC₅₀ was 17.39%, belonging to the strongest toxicity level. The EC₅₀ of E, H stages were 163.6% and 252.4% respectively. Both belonging to the no toxicity level. The total toxicity emission factor(TEF) of CEH was 472.021 TU•m³•t^-1.The TEF of C stage was 393.88 TU•m³•t^-1, about 83.45% of the total toxicity emission factor. The TEF of E and H stages was 10.03% and 6.52% respectively.

Key words: 发光细菌, 毒性, 漂白废水, 毒性排放负荷

摘要： 采用发光细菌法对苇浆CEH三段漂白废水进行了毒性研究，其中C段废水的毒性最大，其EC₅₀为17.39%，属于强毒级别;E段、H段废水的EC₅₀分别为163.6%、252.4％，均属于无毒级别.苇浆CEH漂白工艺总毒性排放因子（TEF）为472.021 TU•m³•（吨浆）^-1，其中C段废水的毒性最大，其TEF为393.88 TU•m³•（吨浆）^-1，约占总量的83.45％，其次是E段废水，约占10.03％，H段最小，约占6.52％.

关键词: 发光细菌, 毒性, 漂白废水, 毒性排放负荷