Department of Zoology, University of Kalyani, Kalyani, WB, India.
J Environ Sci Health B. 2009 Aug;44(6):578-83. doi: 10.1080/03601230903000602.
Static bioassays were made in the laboratory to determine lethal concentration of the pyrethroid pesticide fenvalerate [(RS)-alpha-cyano-3-phenoxybenzyl (RS)-2-(4-chlorophenyl)-3-methylbutyrate] for the freshwater catfish Clarias gariepinus and effects of sublethal concentrations of the pesticide on some biochemical parameters of the fish. For exposure periods of 24 to 96 h, LC(50) values of fenvalerate ranged from 5.83-4.76 micro g/L and 4.24-2.94 micro g/L, respectively for water and acetone soluble fenvalerate. Two sublethal concentrations of fenvalerate were used in the bioassays for biochemical parameters: 2.1 micro g/L for 24 h and 1.4 micro g/L for 96 h exposure, both concentrations representing 50% of LC(50) value of acetone soluble fenvalerate for the respective exposure period. Hepatosomatic index, liver glycogen, alkaline phosphatase of liver and ascorbic acid of blood, liver, and kidney decreased while haemoglobin (Hb) %, plasma glucose levels and acid phosphatase level of liver increased after 24 h exposure to 2.1 micro g/L fenvalerate. Longer exposure (96 h) to even a lower concentration (1.4 micro g/L) of fenvalerate resulted in reduction of all the parameters (except Hb %) tested as compared with control. Fish previously fed for 60 days with a diet supplemented by a high level of ascorbic acid (100 mg/100 g diet) could reverse most of the effects caused by 24 h exposure to 2.1 micro g/L fenvalerate. A lower level of ascorbic acid (50 mg/ 100 g diet) supplement could not influence these effects of fenvalerate. Even the higher dose of ascorbic acid supplementation (100 mg/100 g diet) could not relieve the stress parameters, except for Hb% and HSI, when the pesticide was applied at 1.4 micro g/L for a longer time period (96 h).
实验室进行了静态生物测定，以确定拟除虫菊酯农药氰戊菊酯[(RS)-α-氰基-3-苯氧基苄基(RS)-2-(4-氯苯基)-3-甲基丁酸酯]对淡水鲶鱼（Clarias gariepinus）的致死浓度，以及亚致死浓度对鱼类某些生化参数的影响。在 24 至 96 小时的暴露期内，水可溶和丙酮可溶氰戊菊酯的 LC50 值分别为 5.83-4.76 µg/L 和 4.24-2.94 µg/L。在生化参数的生物测定中使用了两种亚致死浓度的氰戊菊酯：24 小时时为 2.1 µg/L，96 小时时为 1.4 µg/L，这两个浓度分别代表丙酮可溶氰戊菊酯在各自暴露期 LC50 值的 50%。暴露于 2.1 µg/L 氰戊菊酯 24 小时后，肝体比指数、肝糖原、肝碱性磷酸酶和血液、肝脏和肾脏中的抗坏血酸降低，而血红蛋白（Hb）%、血浆葡萄糖水平和肝酸性磷酸酶水平升高。与对照组相比，即使暴露于更低浓度（1.4 µg/L）的氰戊菊酯更长时间（96 小时）也会导致所有测试参数（除 Hb%外）降低。先前用含有高水平抗坏血酸（100 mg/100 g 饲料）的饲料喂养 60 天的鱼，可以逆转暴露于 2.1 µg/L 氰戊菊酯 24 小时引起的大多数影响。较低水平的抗坏血酸（50 mg/100 g 饲料）补充不能影响氰戊菊酯的这些影响。即使在较长时间（96 小时）应用 1.4 µg/L 农药时，较高剂量的抗坏血酸补充（100 mg/100 g 饲料）也不能缓解应激参数，除了 Hb%和 HSI。
