Determination of heavy metal background concentration in bottom sediment and risk assessment of sediment pollution by heavy metals in the Hrazdan River (Armenia)

The purpose of this study is to determine background concentrations of heavy metals in bottom sediments, as well as to characterize potential danger of heavy metals in bottom sediments of the Hrazdan River. Linear regression method was used to determine background concentrations of metals in bottom sediments. While using this method, the linear regression of determining metal with a comparative element was used: The cobalt was chosen as a relative element, which is conditioned by the absence of significant sources of cobalt in this river. Risk assessment index of Hakanson was calculated for evaluation of bottom sediments contamination by heavy metals. It is obtained that in this part of the Hrazdan River basin potential ecological risk caused from bottom sediments contamination by heavy metals is not high.