(full paper is archived in the Miller Library)
Title: Bisphenol A causes disruptions in the cell cycle of the
zygotes and embryos of the purple sea urchin, Strongylocentrotus
Student Author(s): Li, Erica
Faculty Advisor(s): Epel, David
Location: Final Papers Biology 175H
Date: June 2004
Abstract: Bisphenol A (BPA), a common chemical found in polycarbonate plastic containers, is suspected to damage animal health. While many studies on BPA have been done on terrestrial vertebrate models, few have been conducted on marine invertebrates. Because BPA is found in harbours, it is important to find out if we need to be concerned about BPA pollution of the marine ecosystem. This study examines the effects of BPA on the early development of the purple sea urchin, Strongylocentrotus purpuratus. The results show that the vast majority of the embryos develop normally when exposed to concentrations at or below 1 mM up to the late prism stage; a few exogastrulating embryos appear as a result of BPA exposure, but the number of exogastrulating embryos does not increase with increasing concentration. BPA inhibits formation of the blastocoel in S. purpuratus embryos at concentrations greater than 1 mM. At concentrations greater than 5 mM, BPA significantly delays cell division, apparently affecting the mitotic apparatus of the zygote and preventing chromosomes from condensing and migrating properly. The concentrations used in this study are orders of magnitude higher than what has been found in the environment, indicating that BPA may not be of concern in marine ecosystems.