Bio-elimination of lead (Pb) from the organs of red tilapia (Oreochromis sp.) using Gliricidia sepium compost as a feed additive.

This study aimed to evaluate the effectiveness of Gliricidia sepium compost as a feed additive and the optimum dose to reduce the levels of lead (Pb) in the muscles of cultured red tilapia (depuration). G. sepium compost was added to the fish diet at the dose of 0 g kg (control), 10 g kg, 20 g kg, 30 g kg and 40 g kg, fed three times daily. Experiments have been conducted on a laboratory scale. The fish with an average weight of 100 g were cultivated for seven days in an aquarium with the size of 50×33×30 cm filled with 40 L water at a density of 20 fish per aquarium. The results showed that addition of G. sepium compost at a dose of 30 g kg for seven days lowered the Pb concentration in red tilapia flesh to a level safe for human consumption (< 0.3 mg kg). A corresponding concentration of Pb in the culture media suggested that Pb was released from fish’s body into the water. Therefore, it could be concluded that G. sepium compost added to the diet could be used for bio– elimination of Pb in red tilapia.