Heavy metals in seawater, sediments and marine organisms in the Gulf of Chabahar, Oman Sea

Abstract

Levels of the heavy metals Copper (Cu), Zinc (Zn), Lead (Pb), Cadmium (Cd), Chromium (Cr), Nickel (Ni), Iron (Fe) and Manganese (Mn) were determined in coastal water, sediments and soft tissues of the Saccostrea cucullata, from the intertidal zone at five stations in the Gulf of Chabahar on the Iranian coasts along the Oman Sea. The concentrations of heavy metals in seawater ranged between 3.37 to 5.74, 18.01 to 22.62, 4.24 to 4.52, 0.15 to 0.19, 20.16 to 21.46, 16.42 to 17.14, 15.43 to 24.76 µg L-1 and 7.06 to 8.67 µg L-1 for Cu, Zn, Pb, Cd, Cr, Ni, Mn and Fe, respectively. The corresponding concentration values in the sediments were 46.79 to 54.76, 40.14 to 43.12, 25.63 to 28.23, 0.53 to 0.63, 47.16 to 51.43, 26.45 to 28.68, 52.13 to 53.46 and 84.42 to 89.14 µg g-1 for Cu, Zn, Pb, Cd, Cr, Ni, Fe and Mn, respectively. The highest accumulated metals were Zn, Cu and Mn in, S. cucullata while the lowest one was Cd. The highest concentrations of all metals in seawater, sediments and Oyster were recorded at Tiss harbour eastern parts of the Gulf, while the lowest concentrations were recorded at Damagheh. Based on this research, land based activities; shipping activity and the sewage disposal from vessels and residential area close to these harbors are the main source of metal pollution in the Gulf of Chabahar.