Buprofezin toxication implicates health hazards in Nile tilapia (Oreochromis niloticus)

The objective of this study was to investigate the toxic effects of buprofezin insecticide on Nile tilapia (Oreochromis niloticus). The fish were exposed to buprofezin at 100 mg/L for 28 days. Compared to control, activity of serum transferases and levels of urea and creatinine showed significant increases. Oxidative stress was recorded manifested by elevated levels of malondialdehyde (MDA), reduced concentrations of reduced glutathione (GSH) and inhibition of activities of superoxide dismutase (SOD) and catalase (CAT) in liver and kidney. Examination of peripheral RBCs revealed elevated frequency of micronucleated cell. Interleukin 1 beta (IL‐1β) gene was upregulated in liver, muscle and brain, while that of cyclooxygenase 2 (COX‐2) gene increased in liver and muscle, but not in brain. Histopathological alterations were recorded in liver, kidneys, brain, gills, pancreas, spleen, intestine, muscle and ovaries. The immunohistochemical detection of caspase‐3 in the liver revealed no differences between treated and control groups; however, the expression of inducible nitric oxide synthase (iNOS) was demonstrated in hepatocytes and hepatopancreas in buprofezin‐treated group compared to control. It has been concluded that the tissue damage induced by buprofezin in Nile tilapia is mediated by oxidative stress and inflammatory response but not by apoptosis.