Abstract:
In order to study the morphological of heavy metals in different components of
Ruditapes philippinarum,the cytoplasm,nucleus and mitochondria three components were prepared by differential centrifugation,and the metals with different forms were extracted by sequential chemical extraction procedures. The total contents of plumbum,zinc and cadmium in the three components and the contents of different existing forms were determined by inductively coupled plasma-atomic emission spectroscopy. The recovery rates of heavy metals by the sequential chemical extraction procedures were calculated. The results showed that plumbum and cadmium were the highest in the cytoplasm,and zinc was mainly found in the nucleus and mitochondria. Lead elements were mainly in the nucleus,cytoplasm,and mitochondria in a sulfide-bound state. The combined content of sulfide-bound state was 75.24%,71.29% and 50.71% of the total plumbum contents of each component. Zinc had the highest contents in the nucleus in the residual state. The residual state was 34.51% of the total amount of zinc in the nucleus. Zinc in the cytoplasm mainly existed in a commutative state. The exchangeable state was 35.21% of the total amount of zinc in the cytoplasm. Cadmium existed in three states(organic-bound state,sulfide-bound state and exchangeable state). The recovery rates of heavy metals of lead,zinc and cadmium in different components of
Ruditapes philippinarum determined by sequential chemical extraction procedures,were 50.71%~99.08%,and the recovery rate of cadmium was the highest,reaching more than 93% among the three components. In summary,the three metals of plumbum,zinc and cadmium in the cytoplasm of
Ruditapes philippinarum were mostly in the sulfide-bound and exchangeable states. The two forms of metals were easily released into the environment. The two elements of zinc and cadmium in the nucleus and mitochondria mainly existed in the state of residue and organic matter,and the two forms of the metal were relatively stable.