Survey of Heavy Metal Bioaccumulation of Bivalve Seashell in Off-shore Area of Dongzhai Harbor

LIN Yijia; JIAN Li; KOU Yanqiao; ZHENG Yuanwei; DU Ruixian; BI Enze

doi:10.19672/j.cnki.1003-6504.2018.08.004

Abstract：This paper reports on a survey of the bioaccumulation of heavy metal contained in bivalve seashells of four species, i.e. Geloina coaxans, Tapes dorsatus, Cyclina sinensis and Ruditapes philippinarum, and the assessment of food safety risk around the off-shore area of Dongzhai Harbor. The results of this survey showed that there appeared discrepancies of heavy-metal bioaccumulation amount in bivalve tissues and species: with higher levels in gill and viscera than in muscle tissues; heavy-metal concentration of Geloina coaxans was commonly higher than that of others.With respect to the different environmental media, heavy-metal content was the highest in suspended particles followed by sediment and seashell, then the off-shore sea water; as to the biota-sediment accumulation factor (BSAF) of the four seashell species, the bioavailability of heavy metals from sediments ranked in the descending order as Cd＞As ≈ Zn＞Cu＞Cr＞Pb. It was also showed that heavymetal content of the seashells was more correlated to the sediments than to off-shore sea water and suspended particles; contents of Zn, Cr and As in the soft part of Geloina coaxans were significantly positively correlated with those in the sediments;contents of Cr and As in the soft part of Tapes dorsatus were notably positively correlated with those in the sediments, while Cr content in the soft part of Ruditapes philippinarum was remarkably positively correlated with that in the sediments. The risk assessment based on the relative safety limit standard revealed that the content (wet weight) of As was rather high in the muscle samples of the seashells, so the food safety risk was greater.