Assessment of heavy metal contamination in urban soil (Tuzla District, Istanbul, Turkey)

Abstract

In this study, the heavy metal contamination in the soils of the selected upstate area of Tuzla District, which is located in the Anatolian side of Istanbul, Turkey, was investigated. The current status of the soil was evaluated using geo-accumulation index (I-geo), enrichment factor (EF), potential ecological risk (E-r), risk index (RI), and pollution load index (PLI). The average values of I-geo for Cu, Pb, Zn, Cd, and Hg were found as 0.310, -0.013, 0.424, -0.115, and 0.087, respectively. According to the Igeo classifications, the soil qualities of the study area were determined to be uncontaminated, and uncontaminated to moderately contaminated. The average EF values of these metals were determined to be between 2 to 5, which means that the soil was in moderate enrichment categories. The E-r risk of the soil at the sampling points were defined generally as low ecological risk categories except for the SL1 and SL2 sampling points. SL1 and SL2 were detected to have moderate ecological risk. In addition, the average PLI was found as 1.76, and according to this PLI value, the contamination of study area soil was identified as moderately polluted to unpolluted. Consequently, the results of the study indicated that some locations in the study area were affected by anthropogenic activities.