[Cadmium accumulation in tissues of the mussel Mytilus galloprovincialis]

Studies have been made on cadmium accumulation in tissues of mussels kept within 20-60 days in water artificially enriched by Cd up to 20-100 micrograms/l. Irrespectively of cadmium concentration in the medium, its accumulation in tissues decreases in the following order: mid-gut gland, gills, gonads, mantle, adductor. Maximum concentration of Cd was found in the digestive tubuli of the mid-gut gland by X-ray microanalysis. The increase in S and, to a lower extent, P concentrations in these tubuli was also observed. It is suggested that the latter is due to immobilization of Cd by metal-binding proteins as well as to lyzosomal vesicles involved into detoxication of Cd. The increase in the external cadmium up to 100 micrograms/l did not affect the level of K, Ca and Mg in tissues of the mussel.