Assessment the Leachable Heavy Metals and Ecological Risk in the Surface Sediments inside the Red Sea Ports of Egypt

Abstract

The concentrations and distributions of the leachable heavy metals (Co, Cu, Zn, Ni, Cd, Mn, Pb and Fe) were investigated in the fine sediment fractions (O3, O4 and O5) collected from the Egyptian Red Sea Harbors at Hurghada, Safaga and Qusier. The three fractions were the essential heavy metal carriers and were formed the main constituent of the marine sediments with percentages exceed 50% at the most of studied stations. The accumulation sequence of the metal carriers at Hurghada was O5 >O4> O3, however at Safaga and Qusier, it was O5 >O3> O4. Fe and Mn showed the highest values at Safaga (7483 and 306.3 µg/g, respectively) due to the high terrigenous inputs from the different shipment operations and the wastewater effluents. The highest values of Zn, Cu, Ni and Pb were recorded in the marine area off Hurghada ports (330.38, 298.40, 91.4 and 101.02 µg/g, respectively), which attributed to the coastal based activities at Hurghada shipyard and fishing berth. Meanwhile the highest levels of Co and Cd were observed at the old port of Qusier (5.85 and 4.19 µg/g, respectively). The correlation coefficient and principal component analysis (PCA) indicated the anthropogenic sources of Cu, Zn and Pb in front of Hurghada ports. Based on the SQGs, the concentrations of Co, Fe, Mn, Zn and Pb were below the lowest effect level (LEL) with limited severity for Cd, Cu and Ni at Hurghada shipyard but lower than the sever effect level (SEL). The principal component analysis (PCA) showed correlations between Fe, Mn and partially Cd as well as the strong positive correlations for Cu with Zn and Pb suggesting common source of contamination that is likely originated from the terrestrial materials associated with the shipping of ores and coastal activities. According to the Enrichment factor (EF) and the geo-accumulation factor (Igeo), Cu and Pb were the highest enriched elements due to anthropogenic contamination; consequently the studied ports were classified as moderately to highly contaminated by Cu and Pb at Hurghada.