Acta Ichthyologica et Piscatoria 29(2): 73-80, doi: 10.3750/AIP1999.29.2.06
Physiological and histological changes in Tilapia zillii (Gerv.) exposed to sublethal concentrations of the effluent of the Egyptian Copper Works
expand article infoM. Mourad, O. Wahby
Open Access
Abstract
The physiological and histological changes in Tilapia zillii (Gerv.) after exposure to sublethal concentrations of the effluent of the Egyptian Copper Works have been investigated. The results of acute toxicity test showed that the LC50 was 25 cm3/dm3, which means that this waste water is highly toxic. The results of physiological and histological changes in Tilapia zillii (Gerv.) showed that, fish were under considerable stress during exposure to sublethal doses of this waste water. Physiological response of fish revealed a significant disturbances in respiratory system, fish metabolism, and ionic osmoregulation. Pathological changes attributed to heavy metals were observed in the gills, liver, and kidney. Bioaccumulation of copper was highest in the liver, followed by the gills, and flesh. It is concluded that the waste water of the Egyptian Copper Works was not acceptable to discharge to drainage canal. Moreover, this plant should institute appropriate in-plant control to reduce emission of heavy metals.