Study On Heavy Metal Content In Oyster Shell From Dalian And Its Relevance To Sea Water

Heavy metal pollution of coastal water caused by the urban industry and human activities becomes a hot topic nowadays. Due to the effect of biotic enrichment, biotic amplification and biotic accumulation, continuing contamination of heavy metal with low concentration can also lead to coastal biotic accumulation, impacting on the seawater environment as well as the fishery development. Therefore, it is of great significance to observe the change of heavy metal in the ocean.Indicators for monitoring marine heavy metal are usually seawater, sediment and marine organism. Among the three pathways, the most popular one is indicating the variety of marine heavy metal by marine organism. Inaccuracy and lack of representation exist in all of the three pathways of acquiring monitoring data.Contents of Zn, Cu, Cd and Pb in Shell of oyster and offshore water from Dalian gulf, Laohu beach, Fujia Zhuang beach, Lingshui bay, Lvshun and Jinzhou are studied by Anodic Stripping Voltammetry in order to establish a relationship between offshore seawater and heavy metal content in shells. Through monitoring the seawater and shells we researched whether the shells could replace the soft tissue of oyster shells as an indicator of marine environment changes in hope of finding a more convenient and accurate carrier for monitoring marine heavy metal.The HAc-NaAc buffer (PH=4.0～4.5) is used as electrolytic liquid, the metal contents in the oyster shell from six coastal sites in Dalian are investigated by Second-order Differential Anodic Stripping Voltammetry. In comparison with seawater, it is found that the content of heavy metal in oyster shell is closely in agreement with the concentration of metal in seawater. The relative coefficients for metal Zn, Cd , Pb and Cu are 0.9430, 0.9822, 0.9930 and 0.9815, respectively. The relative standard division (RSD) was among 0.11～1.16, the reproducing rate 93～105%. In conclusion, firstly, the oyster shell is an effective indicator for water quality concerning heavy metals contaminations instead of using the tissue of seashell. Secondly, it is possible to...