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Heavy metal concentrations in the soft tissues of swan mussel (Anodonta cygnea) and surficial sediments from Anzali Wetland Iran. Environ Monit Assess 163(1-4):195-213

Iran Fisheries Research Organization, Tehran, Iran.
Environmental Monitoring and Assessment (Impact Factor: 1.68). 03/2009; 163(1-4):195-213. DOI: 10.1007/s10661-009-0827-7
Source: PubMed

ABSTRACT Concentrations of cadmium, copper, and lead were determined in surficial sediments and the soft tissues (foot and gills) of swan mussel Anodonta cygnea from two sampling sites in Anzali wetland, which is an internationally important wetland registered in the Ramsar Convention. The metal contents in the mussel species from the studied region were comparable to other world areas. In most cases, the levels of the metals either fell within the range for other areas or were lower. There were significant differences between the tissues for the accumulation of Cd and Pb. Only in the case of Pb accumulation in gills significant differences between the specimens from the selected sampling sites could be observed. Age-related correlations were found in the case of Cu accumulation in foot and Cd levels in gills. No weight-dependent trend could be observed for the accumulation of the three elements. There was significant negative width-dependent relationship in the case of Cu. A significant negative correlation was also found between the maximum shell height and Cu accumulation in the gills. The only association among the elements in the selected soft tissues was found between Cd and Pb. Highly significant differences could be found between the sampling sites from the concentration of the elements in sediments point of view. The pattern of metal occurrence in the selected tissues and sediments exhibited the following descending order: Pb, Cu>Cd for gills, Cu>Pb, Cd for foot, and Cu>Pb>Cd for sediments. The mean concentrations of Cd and Pb in the sediments from the study area were higher than the global baseline values and world average shale. In the case of Cu, our results were somewhat higher than the baseline values but well below the world average shale.

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    • "Sediment samples were microwave-digested in Teflon bombs using a mixture of HNO 3 and HF according to MOOPAM Instruction (2010). The digested samples were transferred to tightly sealed linear polyethylene (Nalgene) containers to avoid adsorption of metals from digested solution and kept at 4 °C prior to further analysis (Pourang et al. 2010). The total organic matter (TOM) in the sediments was determined by drying for 24 h at 60 °C, combusting in a muffle furnace (at 600 °C for 24 h) and calculating differences in weights according to H\aque et al. (1997). "
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