Abstract: 8810 A. Introduction

The Phylum Echinodermata encompasses a widely distributed and diverse group of marine animals. The class Echinoidea includes sand dollars and sea urchins, organisms that are common inhabitants of rocky shores and ocean bottoms over all depth ranges. Many echinoid species are maintained easily in the laboratory and are responsive to simple methods of spawning inducement. Gametes and embryos are easily obtained and reared in the laboratory and have been the subject of scientific research for more than 100 years.¹ Numerous species have been used, and laboratory techniques have been developed that use various stages of each organism’s life cycle.^2–6

Toxicity tests involving short-term exposure of gametes or embryos are of comparable or greater sensitivity to many contaminants than tests with other marine species and life stages.^7–11 Echinoid toxicity tests can be performed on small volumes (≥2 mL) over short periods (1–96 h), and under static conditions without feeding. These tests have been used successfully to evaluate the toxicity of effluents, receiving waters, chemicals, and sediments if the test samples’ salinity is near typical ocean levels (28–34 g/kg). Recent adaptations of these test methods have expanded applications to include evaluation of genotoxic effects,¹² interstitial water,¹³ and toxicity identification evaluation (TIE) studies.¹⁴ Methods similar to these have been proposed or recommended as components of regulatory programs.^2,15–17