The Study Of Accumulation And Elimination Of The Heavy Metal Cadmium In Shellfish And The Edible Safety Of Shellfish

The accumulation and elimination of the heavy metal Cadmium in shellfish and its effect to the accumulation of other heavy metal are studied in this paper. In addition ,We also studied the accumulation of Cd, Gr, As, Se, Pb, Zn, and Cu--seven heavymetals in six kinds of shellfish along five coast areas of Shandong Province . This paper is helpful to the establishment of the evaluation system of shellfish processing and consumption.The Argopecten irradiams's acute toxicity experiment of Cd2+ was carried out with five concentration according to the toxicity experiment of aquatic animals. Through the Linear regression of probability unit and concentration logarithm, we got the Lc50 Cd2+ to Argopecten irradiams at 24h, 48h, and 96h, which are 5.85mg/l, 4.52mg/L, 3.45mg/L respectively. The safe concentration of Cd2+ in Argopecten irradiams is 0.345mg/l.According the results of acute toxicity experiment, we studied the accumulation and elimination of Cadmium in Argopecten irradiams and the effect of Cadmium concentration to Argopecten irradiams's accumulation of other heavy metals. The Cadmium concentration in this experiment is as follows: 0.001mg/l, 0.0025mg/l, 0.005mg/l, and 0.01mg/l. The experiment showed that Argopecten irradiams has an high ability of accumulating Cadmium. The higher the Cadmium concentration is and the longer the period of experiment is lasting, the higher the Cadmium concentration in Argopecten irradiams is. It also can be concluded that gull' ability of accumulation of Cadmium is higher than that of muscle. Thus, though it is safe to eat muscle, gull cannot be eaten for its high content of Cadmium. For example, the content of Cadmium in gull of Argopecten irradiams is up to 1.0mg/kg after it is cultured in seawater with 0.0025mg/l Cd concentration for 25 days. In addition, high Cadmium concentration in seawater can inhibit the accumulation of Zn but increase the accumulation of Se. It has no effect on accumulation of Cr and As.Furthermore, we inspect the content of seven elements (Cd, Cr, As, Se, Pb, Zn, Cu) in six shellfish Venerupis Variegata, Cyclina Sinernsis, Oyster, Sinonvacula constricta, Meretrix Meretrix, Mytilus, Edulis in five coast areas along Shandong Province. The results showed that double-shell-shellfish were severely polluted by heavy metals, which is adopted as indicating animal of marine environment. The contents of the seven elements in the six shellfish are all above criteria. It can also be concluded that the contents of heavy metals in shellfish are positively correlative to that in seawater.