Cadmium in the saucer scallop, Amusium balloti, from Western Australian waters: concentrations in adductor muscle and redistribution following frozen storage

Geographic and seasonal variations in the concentration of cadmium in the adductor muscle of saucer scallops, Amusiurn balloti, were determined for scallops collected from five sites off the Western Australian coast throughout 1985. Mean cadmium concentrations for adductor muscles from whole frozen scallops from each of the five sites ranged from 0.41 to 1.44 mg kg-1 wet weight and were below the maximum permitted concentration of 2.0 mg kg-1 set by the Australian National Food Authority. Most of the cadmium (about 80% of the total) in the scallops was in the non-edible digestive gland. Subsequent work revealed that adductor muscles of whole frozen scallops contained more cadmium than did adductors of scallops that had been processed live because of redistribution of cadmium from the digestive gland, with the degree of redistribution depending on the time in frozen storage. Cadmium in A. balloti from Western Australian waters was likely to be of natural origin because the highest concentrations were found in animals collected in remote areas where human activities have had no significant effect.