Preliminary Study on Accumulation and Depuration of Copper, Zinc, and Lead in Tilapia (Oreochromis mossambicus) under Laboratory Conditions

Abstract: tilapia (oreochromis mossambicus) was studied for the uptake and elimination of single metals namely copper (cu), zinc (zn) and lead (pb) under laboratory conditions. tilapia was acclimatised at 25 ± 2°c for 4 days. the dissolved oxygen and ph of water samples were maintained at 6 - 7 mg/l and 7.6 ±0.1 respectively. the exposures to cu (0, 5, 10, 15 and 20 mg/1), zn (0, 10, 15, 20 and 25 mg/l) and pb (0, 1, 2, 3 and 4 mg/l) over a period of 4 days were followed by 4 days of depuration. the accumulation and depuration patterns of cu and zn were not apparent and statistical analysis (t-test) did not show any significant difference (p>0.05) for both phases. the results indicate that tilapia can be used as a biomonitor for pb as there was significant difference (p<0.05) between accumulation and depuration of pb, particularly for higher exposures (3 mg/l and 4 mg/l pb).