Abstract:

In this paper, the content of 6 heavy metals, i.e., Cd, Cr, Pb, Ni, Cu and Zn were analyzed in five dry tissues of adductor muscle , hepatopancreas, gill, mantle, foot of Meretrix meretrix cultured in Haizhou bay pond. Results indicated that adductor muscle and hepatopancreas were major heavy metal enriching tissues. The contents of Cr, Pb and Ni in adductor muscle were highest among the five tissues, and were 58.981, 4.298μg/g and 10.873μg/g, respectively, which had significant difference with those in other tissues (P＜0.05). The concentration of Cu and Zn were 0.844μg/g and 58.076μg/g in adductor muscle, obviously lower than that in hepatopancreas 17.776μg/g and 173.147μg/g, respectively (P＜0.05). On the contrary, the concentration of Cd and Ni was lower in hepatopancreas (0.140μg/g and 4.807μg/g) than that in the other tissues (P＜0.05). Among the six heavy metals, the highest content was Zn (173.147－58.076μg/g), and the lowest was Cd (0.140－0.336μg/g), followed by Pb (1.549－4.298μg/g). The major contaminated tissue was the adductor muscle for M. meretrix and the contamination index for Cr, Ni and Pb ranged from 1.52 to 6.40, however, there was a minor contamination in foot and the contaminative index was only 0.01－0.96 except for Ni. All the five tissues were slightly contaminated by Ni and the contamination index ranged from 2.77 to 6.40, but the contamination index for Cd and Cu were in the range of national standard for health aquatic products.

Key words: Meretrix meretrix, tissues, heavy metal, contamination evaluation