Estimating the bioaccumulation of heavy metals in some algae marine at the coast of Al Khums

Abstract

The aim of the study is to estimate the bioaccumulation of some heavy metals Lead (Pb), Cadmium (Cd) and Zinc (Zn) in some marine organisms namely: (Enteromorpha compressa and Jania rubens;). In addition, these elements were estimated in samples of seawater surrounding these organisms. These samples were collected from three sites in the city of Al-Khums (Beach of Al-Khums Park, Barco Beach and the beach opposite the Power and Desalination plant). These samples were collected during the period from Autumn 2017 to Summer 2018 in order to know the extent of the accumulation of heavy elements in these organisms. However, these organisms are considered part of the food chain, which are transferred to the human at the top of the food pyramid. The concentrations of heavy metals in the studied samples were determined using the Atomic Absorption Spectroscopy (CONTRAA700 analytikjena) at the Sadeem Laboratory. After heavy metal extraction from samples seawater and samples marine organisms, results show that, the concentration of the elements in most samples exceeded the limits allowed by the World Health Organization (WHO) and the Food and Agriculture Organization (FAO). There was an obvious variation in the concentration of heavy elements in seawater at the three sites. The highest concentration of Lead (Pb) and Zinc (Zn) were (13.542 and 8.243) mg./ L, respectively, which were observed in summer at the Barco Beach site. The highest concentration of cadmium (Cd) was (0.069) mg./ L. in Autumn at the beach opposite to the Power and Desalination plant. The bioconcentration factor (BCF) has been calculated. The highest BCF values of Pb, were (570- 590) mg./ L. in E. compressa and J. rubens respectively times in accordance to its concentration of water. As well as the highest BCF, values of Cd were (597.1-84.2) mg./ L. in E.compressa and J. rubens respectively times in accordance to its concentration of water. Finally, BCF values of Zn were 181.4 and 200.9 mg./ L. in E.compressa and J. rubens respectively times in accordance to its concentration of water. This means that there is a bioaccumulation in the selectively studied organisms varied according to type and location.

Keywords: Enteromorpha compressa,Jania rubens , heavy metals.