Cerium Inhibits the Cadmium Uptake of Pacific Oyster Crassostrea gigas

Özet

Ce3+ is a potential antagonist of Cd due to their similar ionic radius. Its effect on the bioaccumulation of Cd2+ in pacific oyster Crassostreagigaswas explored through laboratory experiments. The oysters were exposed to 5, 10 and 25 ?mol/LCe(NO3)3 in the presence of 25 ?g/L Cd2+ (0.22 ?mol/L) for 12 days and the concentrations of Cd, Ca, Zn as well as Cu were indicated in the whole soft tissues and separate organs. Ce3+ in all the three doses significantly inhibited Cd2+bioaccumulation in the oysters on day 12 and the inhibition ratios reached 30%, 31% and 41% respectively. Organ-level analysis revealed that Ce3+ possibly exerted its inhibitory action by delaying the saturated absorption of Cd2+ in the gill. Ce3+in all the three doses antagonized the negative effects of Cd2+ on Ca concentration and restored the its level to the normal range on day 12, but 25 ?mol/L Ce3+ decreased the Zn and Cu concentrations by up to 27% and 88% respectively. It was concluded that Ce3+ could markedly inhibit the Cd2+ bioaccumulation of Crassostreagigasand the presence of Ce3+ must be considered in marine pollution assessment by using oysters as the bio indicator.