GENOTOXIC AND DEVELOPMENTAL EFFECTS IN SEA-URCHINS ARE SENSITIVE INDICATORS OF EFFECTS OF GENOTOXIC CHEMICALS

Purple sea urchin (Strongylocentrotus purpuratus) gametes and embryos were exposed to three known mutagenic chemicals (phenol, benzidine, an d pentachlorophenol) over concentration ranges bracketing the effect l evels for fertilization success. Normal development and cytogenetic ef fects (anaphase aberrations) were assessed after the cultures were all owed to develop for 48 h. Using radiolabeled chemicals, we also charac terized concentrations in the test water as well as doses in the embry os following 2- and 48-h exposures. We observed dose responses for all chemicals and all responses, except for phenol, which showed no signi ficant effect on development. Fertilization success was never the most sensitive end point. Anaphase aberrations were the most sensitive res ponse for phenol, with an LOEC of 2.5 mg/L exposure concentration. Ana phase aberrations and development were equivalent in sensitivity for b enzidine within the tested dose range, and an LOEC of <0.1 mg/L was ob served. Development was the most sensitive response for pentachlorophe nol (LOEC 1 mg/L). The LOEC values for this study were generally lower than comparable data for aquatic life or human health protection. We conclude that genotoxicity and development evaluations should be inclu ded in environmental management applications and that tests developed primarily for human health protection do not reliably predict the effe cts of toxic substances on aquatic life.