Effect of cadmium on gametogenesis and offspring of the sea urchin Strongylocentrotus intermedius

Effects are examined of chronic exposure to cadmium sulfate(5, 1, 0.5 and 0.1 mg Cd 1-l) on gametogenesis of mature sea urchins Strongylocentrotus intermedius, and on the development of their offspring. Embryogenesis in uncontaminated sea water (33 %O S) was observed up to the early pluteus. At 5 mg Cd I-', test animals died within several h; at 1 mg Cd 1-l within several d; at 0.5 mg Cd I-' within 1 mo. Cd concentrations of 0.5 and 1 mg 1-' induced obvious anomalies in ovocytes. Long-term exposure of adults to 0.1 mg Cd 1-' produced no changes in external appearance nor any obvious histological alterations in gonads; nevertheless, such exposure led to the production of anomalous sex cells and resulted in inviable offspring.