Heavy Metal Concentrations in Surface Soils of Izmit Gulf Region, Turkey

Abstract A series of experiments were conducted using the soil surface samples collected from rural, urban and mostly industrial sites in the vicinity of the Gulf of Izmit. Soil samples were digested with the selected acid mixture of HCl-HNO3-HF-H3BO3 in a microwave digestion system. The experiments were aimed at investigating the total metal concentrations of cadmium, cobalt, chromium, copper, iron, manganese, nickel, lead, and zinc. Metal contents in soil samples were detected by flame atomic absorption spectrometry (FAAS). From the results of analysis and comparisons among soil types, it is clearly shown that urban and industrial soils were contaminated more than rural soils. Cd was not detected in any of the soil samples. Pb enrichment in urban and industrial soils might be a result of gasoline combustion. Comparison of obtained average metal concentration levels with the world average ones indicated elevated values for Co, Cu, Mn, Pb, and Zn. The mean concentrations of Co, Cu, Mn, Pb, and Zn were found as 22, 33, 842, 37, and 72 mg kg−1, respectively.