Acute Toxicity Test of Zinc Chloride (ZnCl2) in sobaity seabream (Sparidebtex hasta)

The main objective of the present study was to investigate the sensitivity of marine fish sobaity seabream (Sparidebtex hasta) to Zinc Chloride in the toxicity test programs. In practice, experimental setup (Rang Finding Test) was constituted 25 fish (from 193 fish) to be placed in one replicates. All fishes were exposed to ZnCl2 at several selected concentrations 0, 1, 5, 10, and 15 ppm (Rang Finding Test), then the fish were subjected to seven concentrations of ZnCl2 (control, 10, 15, 20, 25, 30, 35, and 40 ppm). Each concentration contained seven fish with three replicate each. There was a simultaneous control group (n= 21; with no heavy metal additions) together with the heavy metal treatments, keeping all other conditions alike. Physicochemical parameters, such as dissolved oxygen, pH, and temperature of fiberglass tank as well as mortality rate of the fishes, were monitored daily. Number of mortality was registered after 24, 48, 72, and 96 hours. LC50 values were determined with probit analysis. The 96 hours LC50 value of ZnCl2 to the fish was found to be 10.27 ppm. The mortality decreased with time, and most of the deaths occurred during the first 24 hours. In addition, behavioural changes increased with concentration enhancement.