Effects of lanthanum on the cadmium uptake of pacific oyster Crassostrea gigas

Abstract

La3+ is a typical Ca2+-channel blocker and its effect on the bioaccumulation of Cd2+ in Crassostrea gigas was investigated in this work. The oysters were exposed to 5, 10 and 25 μmol/L La(NO3)3 in the presence of 25 μg/L Cd for 12 days and the variations of Cd bioaccumulation as well as Ca and Zn contents were determined. La3+ in the three levels inhibited Cd bioaccumulation by up to 36%, 44% and 25% respectively on day 12. Organ-level analysis revealed that La3+ possibly exerted its inhibitory action by delaying the saturated absorption of Cd in the gill. La3+ antagonized the negative effects of Cd2+ on Ca content, but 25 μmol/L La3+ significantly decreased the Zn content in the oysters. It was concluded that La3+ markedly influenced the metal metabolism of Crassostrea gigas and the presence of La3+ must be considered in marine pollution assessment by using oysters as bioindicator.