敌百虫对奥尼罗非鱼幼鱼的急性毒性及安全浓度评价

为研究敌百虫对奥尼罗非鱼幼鱼的急性毒性效应,采用96 h半静水式生物毒性试验方法,在水温(23.5±2.0)℃,溶解氧>5 mg/L的条件下,分别检测在曝气自来水(pH为6.5)和池塘水(pH为8.5)中敌百虫对奥尼罗非鱼幼鱼的急性毒性效应。结果显示:在曝气自来水中,敌百虫对奥尼罗非鱼幼鱼24、48、72、96 h的半致死质量浓度分别为3.68、3.31、2.05、1.57 mg/L,安全质量浓度为0.157 mg/L;在池塘水中,敌百虫对奥尼罗非鱼幼鱼24、48、72、96 h的半致死质量浓度分别为0.35、0.29、0.17、0.13 mg/L,安全质量浓度为0.013 mg/L。试验结果表明,在池塘水中敌百虫对奥尼罗非鱼幼鱼的毒性比在曝气自来水条件下强。

Acute toxicity and safety concentration evaluation of trichlorfon on juvenile tilapia(♀Oreochromis niloticus×♂O.aureus)

The acute toxicities of trichlorfon on juvenile tilapia(♀Oreochromis niloticus×♂O.aureus)cutured in aerated tap water(pH=6.5)and pond water(pH=8.5)were studied at water temperature of(23.5±2.0)℃and dissolved oxygen above 5 mg/L using a static bioassay test.The results showed that:(1)Under the condition of aerated tap water,the median lethal concentration(LC 50)of trichlorfon on juvenile tilapia was 3.68,3.31,2.05 and 1.57 mg/L at 24 h,48 h,72 h and 96 h,respectively,and its safe concentration(SC)was 0.157 mg/L;(2)Under the condition of pond water,the LC 50 of trichlorfon on juvenile tilapia was 0.35,0.29,0.17 and 0.13 mg/L at 24 h,48 h,72 h and 96 h,respectively,and its SC was 0.013 mg/L.The results showed that the toxicity of trichlorfon on juvenile tilapia cultured in pond water was stronger than that on juvenile tilapia cultured in aerated tap water.