Investigation of heavy metal pollution in roadside soils and road dusts along the Kutahya-Eskisehir Highway

Today, due to the technological needs, individual and public transportation activities are increasing. This causes traffic and environmental pollution around urban and intercity roads due to wearing of automobile parts and emission. Heavy metal pollution caused by traffic emissions is one of the most important environmental threats. Heavy metals from emissions could be enriched in water, air, and soil and cause pollution as well. There are many studies on this issue in the literature and there are also studies conducted in our country in recent years. However, there is no study on the Kutahya-Eskisehir Highway which is one of the most important and busiest roads in Western Anatolia bridging the western Anatolia to the Central Anatolia. In this study, the Kutahya-Eskisehir Highway roadside soil and dust samples were collected and these samples were studied for contents of Cu, Pb, Zn, Ni, As, Cr, and Hg heavy metals. The concentrations of the samples were 4.25-77.99 mg/kg for Cu, 7.71-224.02 mg/kg for Pb, 12.50-595.0 mg/kg for Zn, 38.0-1981.10 mg/kg for Ni, 2.0-22.5 mg/kg for As, 21.10-473.10 mg/kg for Cr, and 5.0-500.0 mg/kg for Hg, respectively. In addition, the enrichment factor (EF) and the geo-accumulation index (I-geo) were calculated using these data to evaluate the level of heavy metal pollution in soils and dusts. According to these factors, the roadside soils and dusts of the highway mostly present low- and medium-range pollution and enrichment degrees for Cu, Pb, Zn, As, Cr, and Hg and quite high degrees for Ni.