evaluation of zinc accumulation in tissues of cyprinus carpio and oreochromis niloticus

Cyprinus carpio and oreochromis niloticus were exposed to 0.5 mg l-1 concentration of zn over 1, 15, 30 days and accumulation in several tissues were determined. metal accumulation in these tissues was measured using atomic absorption spectrophotometric techniques. statistical evaluation of the experimental data was carried out by variance analysis and student newman keul’s procedure (snk). highest accumulation of zinc was in gill tissue on day 15, followed by liver and muscle tissues, whereas on day 30 the order was liver, gill and muscle tissues in both species. tissue accumulation of zinc was higher in c. carpio compared with o. niloticus. zn accumulation in the tissues of metal exposed fish increased with increasing exposure periods. one may conclude that the variation of zinc accumulation in tissues might be depended on metabolical, structural and functional differences of both species.