Investigation of spatial and temporal variation of soil pollution in terms of metals in Dilovasi (Kocaeli) industrial region

Today, with the development of industrial activities, the increase in the number of motor vehicles and rapid population growth, heavy metal pollution in the soil has become one of the important environmental problems. This work mainly focuses on heavy metal pollution from industrial origin. The Dilovası region, which contains 45 different industries (185 small and medium-sized industrial plants), is one of the regions where soil pollution is frequently seen. The purpose of this work is (1) to determine the levels of metal pollution causing soil pollution in Dilovası, where industrial activities are very high, (2) to investigate the temporal variation of concentration values of pollutant parameters determined in different seasons, (3) to determine the sources affecting the chemical composition of soil, (4) to evaluate the spatial distribution of parameters determined in the soil. In order to achieve these listed objectives, soil samples were collected in February, July and October of 2015 in 23 different sites in Dilovasi. Collected samples were analyzed in terms of pH and metals (from Li to U). The obtained results revealed that metal concentrations were ranged from 0. 003±0. 003 µg/g for Lu to 21±15 mg/g for Ca. The average soil pH was found as 7. 69±0. 19 indicating alkaline nature of soil. When the obtained results were compared with the Turkish Soil Pollution Control Regulations, it has been found that the limit values for Cr, Ni and Zn were exceeded at some sites particularly for the samples collected in February. Once the results from this study were compared with the ones reported in the literature, we found that data set generated for Dilovasi were within the previously pblished values. Eenrichment factor calculation revealed that ve Sn, Cu, Sc, Ni, Cr, Mo, Sb, As, Cd, Hg and S released to the soil from anthropogenic sources. PMF was applied to the produced data set identified four different factors affecting soil composition in the region. Exposure risk assessment showed that ingestion of soil contaminated with metals does not lead to health risk for both adults and children.