Accumulation, distribution and loss of cadmium in the marine prosobranch Littorina littorea (L.).

In the present investigation cadmium was studied in Littorina littorea exposed to two ambient concentrations and for various exposure times, as well as after a detoxification period of 74 days. The results are expressed as whole body and individual organ burdens of metal. Organ metal analyses, exposure time and external metal concentrations were correlated using tetradic diagrams to represent four different organ burdens. Linear accumulation appeared to occur in the whole soft body at the cadmium concentrations and times studied. There was also a general linear trend in the accumulation of cadmium in the various organs (gills, kidney, digestive gland/gonad complex and remaining tissue), but at certain exposure times the tissue concentration of cadmium differed from what was expected. Different cadmium distribution patterns were observed as a result of the relative intensity of the accumulation and elimination processes. Because of these inconsistent variables it is generally concluded that for bioindication purposes it is preferable to use the cadmium burdens of the whole soft body rather than those of individual organs. For physiological studies of cadmium, however, the pattern of metal distribution in the organs is necessary to describe the metabolic pathways through the organism.