Toxic effects of profenofos on tissue acetylcholinesterase and gill morphology in a euryhaline fish, Oreochromis mossambicus

摘要: Acute and sub-acute studies of profenofos [O-(4-bromo-2-chlorophenyl)-O-ethyl-S-propyl phosphorothioate] on fish, Oreochromis (Tilapia) mossambicus, were carried out to assess the toxicity in relation behaviour, morphology, interactions with targeted enzyme acetylcholinesterase (AChE, EC 3.1.1.7). Profenofos can be rated as highly toxic O. a median lethal concentration (LC50) 0.272±0.0177 mg/l. The inhibitory recovery pattern brain gill AChE was studied vivo after exposure single LC50 multiple exposures sub-lethal concentrations (0.108 mg/l) for 28 days, respectively. LC50-exposed fish exhibited 90% inhibition activity 24 h, completely recovered within 23 days. Electron microscopy revealed an abnormal distinct breakages arches rakers, along deep lesions erosions epithelium. Prolonged at 0.108 mg/l also had similar effects, such damage inhibition. vitro study indicated that is neurotoxic it alters apparent K m values widely concentration-dependent manner, resulting competitive type Based i values, sensitivity greater than tissue, 2.38×10-5 4.62×10-5 M, bioaccumulation head, body viscera estimated regular intervals by gas chromatography method. results accumulation highest followed head body, depuration rates 6.14, 0.16 0.12 µg/h,