CADMIUM UPTAKE AND SEQUESTRATION IN THE PIKE (ESOX-LUCIUS)

1. 1. Pike were exposed to cadmium dissolved in their aquarium water at separate concentrations of 60, 125 and 225 μg/l and the distribution of the metal accumulated in the major body organs was determined. 2. 2. The fractional retention coefficient ([μg Cd/100 g body wt]/[(μg Cd/1) × weeks]) for cadmium was constant at each concentration and at different periods of exposure to the metal. The values measured were remarkably low. 3. 3. When cadmium was introduced into the fish by intraperitoneal injection, the metal was found associated with metallothionein. 4. 4. The amino acid composition and immunochemical cross-reactivity of pike metallothionein were comparable to those of other piscine metallothioneins. 5. 5. The unexpected tolerance of pike to the toxic effects of cadmium when exposed to the metal in the aquatic environment is discussed. © 1990.