Determining Heavy MetalPollution Intensity (Cd, Pb and Cu) in Surface Sediments from Anzali Wetland

Sediments are as a sink of various pollutants, especially heavy metals in aquatic ecosystems; that is, they are the potential source of toxic chemicals. The purpose of this investigation is the study of pollution intensity and source of heavy metals in sediments from Anzali Wetland. Sediment samples were selected from six sites in Anzali wetland in summer 2009. The determination of sediments contamination by heavy metals was performed using a sequential extraction process in four stages. The results showed that levels of cadmium and copper were higher in comparison with the values of the Earth’s crust and of global sediments. In all the stations, the levels for the individual concentration factor for Cd and Cu was more than one. So these elements can be a danger for the health of the wetland because of high bioavailability. The ICF value for the studied metals in the six stations was following: Pb< Cd< Cu In fact, it should be noted that the release of heavy metals from sediments are inthe strong acidic conditions while stations, sediment have a neutral pH.