摘要
Marine copepods, Acartia erythraea, were exposed separately to aqueous Cu and Ag media and to a Cu＋Ag mixture in a series of experiments during which the metal body burden and partitioning in the exoskeleton and polar and nonpolar parts of the animal cells were measured and the uptake and effiux rate constants for Cu and Ag were calculated. The metal uptake and effiux rate constants were 1.04×10^3±1.00×10^2 L·g^-1·d^-1 and 9.28× 102＋ 1.43×10-2 d^-1 for Cu and 1.60× 104＋1.78×10^3L·g^-1·d^-1and 9.23×10^2 -4- 9.1 1×10^3d^-1 for Ag, respectively. For both Cu and Ag, the uptake rate constants when the copepods were exposed to solutions of a single metal were generally higher than that when the copepods were exposed to metal mixtures. The results suggest an antagonistic interaction between waterborne Cu and Ag exists in marine copepods. The different distributions of Cu and Ag among the exoskeleton and polar and nonpolar parts of the copepods revealed that the metal bioavailability in copepods exposed to metal mixtures enhanced in some degree compared to copepods exposed to single metal solutions.
