Tea seed cake is a plant derivative with pesticide properties mainly used for eradication of unwanted fish, it
easily degraded in water leaving an organic fertilizer so it is safe for the environment, this work aimed to study it's toxic
effect on the widely farmed fish in Egypt; Oreochromis niloticus throughout this study its molecular, histological and
biochemical effects on liver and kidney of O. niloticus fingerlings exposed to different concentration of tea seed cake
(1/3, 1/10 and 1/20 LC50). There were an increase of hepatic and renal biomarkers, alanin aminotransferas (ALT),
creatinin and urea concentrations in serum this concomitant with different pathological changes in hepatic and kidney
tissue mainly vacuolization, degeneration, nicrosis, lymphocytic infiltration and haemolysis as well an induction of
superoxid dismutas (SOD) and catalase (CAT) gene expression and increase of their activities in renal and hepatic
tissues of the exposed fish.