Influence of metal exposure history on trace metal uptake and accumulation by marine invertebrates英文书.pdf

ARTICLE IN PRESS Ecotoxicology and Environmental Safety 61 (2005) 145–159 Rapid communication /locate/ecoenv In?uence of metal exposure history on trace metal uptake and accumulation by marine invertebrates Wen-Xiong Wanga,?, Philip S. Rainbowb aDepartment of Biology, The Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon, Hong Kong, China bDepartment of Zoology, The Natural History Museum, Cromwell Road, London SW7 5BD, UK Received 5 July 2004; received in revised form 30 December 2004; accepted 24 January 2005 Available online 16 March 2005 Abstract This paper reviews recent studies on the in?uence of trace metal exposure history on subsequent metal uptake in marine invertebrates, particularly bivalves and barnacles. Trace metal exposure may induce speci?c metal-binding ligands. Metallothioneinlike proteins appear to play an important role in mediating metal uptake and hence accumulation, especially for Cd. Other ligands such as sul?de are important for Ag biokinetic changes in bivalves. The incorporation of trace metals into metal-rich granules appears to have little if any effect in modifying trace metal uptake. Furthermore, metals also interact strongly in their accumulation by marine animals. Generally, dissolved Hg uptake is reduced following exposure to other metals such as Ag, Cd, Cu, and Zn. Preexposure of marine mussels to Zn also causes concomitant changes in the uptake of other metals such as Cd sharing similar transport pathways. In general, barnacles are less responsive than mussels to trace metal exposure, presumably because of the dominance of detoxi?catory pathways in which the accumulated metals are bound in granules (relatively biologically inactive pools). The tissue body burden and the detoxi?catory fate of metals in animals seem to be more important in affecting metal accumulation than the nature of the exposure routes (aqueous vs. dietary) or of the exposure regimes. Trace metal accumulation may also be variable