STUDIES ON THE EFFECTS OF SOME AGENTS ON FERTILIZED SEA URCHIN EGGS, AS A PART OF THE BASES FOR MARINE POLLUTION BIOASSAY I

Abstract

(1) A few series of experiments were made to clarify the effects of 4 factors for marine pollution, tannic acid, kaolin, pH and higher temp, after using sea urchin eggs and embryos for the bioassay. (2) The minimal conc of tannic acid (the main toxic component of extracts from timbers stored in the sea) to inhibit fertilization, cleavage and later development of sea urchin eggs, was 6.3 ppm. (3) Kaolin, the main component of clayey soil, at concs greater than 250 ppm more or less affected fertilization, cleavage and later development. (4) Normal fertilization and cleavages were maintained in Anthocidaris crassispina between pH 7.8 to 8.6, the neutral pH remarkably induced polyspermy, the decrease of pH below 6.6 reduced rates of fertilization and cleavage, and the increase of pH above 9.0 also brought about the reduction in fertilization and cleavage rates followed by cytolysis. (5) Raising the temp by more than 3 degrees C above the usual summer water temp reduced rates of fertilization and cleavage, but promoted polyspermy and cytolysis.