Accumulation of Chromium (VI) in Tissues of Oreochromis niloticus, Cyprinus carpio, Clarias gariepinus, Callinectes sapidus and Its Effect on Protein and Glycogen Levels

Accumulation of chromium in tissues of oreochromis niloticus, cyprinus carpio, clarias gariepinus and callinectes sapidus and its effect on protein and glycogen levels were studied after exposing the animals to 0.5, 1.0 and 2.0 ppm chromium over 7, 15 and 30 days. chromium analysis of the tissue samples were carried out using atomic absorption spectrophotometric methods and tissue protein and glycogen analysis were carried out using lowry and anthron methods respectively. no mortality was observed in any of the chromium concentrations after 30 days of exposure. chromium accumulation increased with increasing metal concentrations and exposure periods in the muscle, gill, liver and the hepatopankreas tissues studied. accumulation was highest in liver tissues of fish whereas in hepatopankreas in c. sapidus except in 0.5 ppm chromium and it was higher in c. gariepinus compared the other two fish species. total protein levels decreased with increasing concentrations of the metal and with prolonged exposure periods except c. carpio, while glycogen levels decreased with increasing exposure concentrations and periods in all the species studied. tissue accumulation of chromium can be explained by detoxification mechanisms and changes in protein and glycogen levels might be due to metabolic and physiological changes caused by the metal.