Degenerative histopathalogical alterations were seen in liver due to chronic exposure of the fish,
Labeo rohita
to chlorides of chromium, nickel and zinc for 30 days. However, more severe degenerative changes were observed in case of zinc chloride exposed fish than nickel chloride and chromium chloride treated fishes, indicating more toxic nature of zinc chloride. There were enlarged nuclei, condensation of cytoplasm and disarray of hepatic cords blood congestion in sinusoids, vacuolation of hepatocytes and necrosis. Heavy metal salts get entered in the cells by readily crossing the cell membranes where interfere with the enzyme systems in the cells resulting into morphological damage and / or their vital functions could be in jeopardy.