A chemometric approach to study the effects of motorway proximity on microelements content in wheat and soil

The present research was conducted to study contamination and to quantitatively determine the microelements Pb, Cd, Hg, As, Zn, Cu, Fe and Mn in roadside soils in the regions in Serbia and in wheat grain grown from those soils. Roadside soil samples and wheat samples were collected from different sites along roadside. Inductively coupled plasma mass spectrometry was used for analysis. Standard scores and the heavy metal index in the soil and wheat grain were calculated by assigning equal weight to applied heavy metals assays. In the soil, the lowest and the highest coefficient of variation were found by determining Mn and Hg content as 0.09 and 10.48 %, respectively, contrary to the wheat where the lowest and highest coefficient of variation were experienced for Hg and Pb at 1.99 and 6.36, respectively. Principal component analysis was applied to the results of analysis comprising the content of eight toxic elements in wheat and soil. It was established that the quantity of analyzed microelements in the wheat is smaller than the quantity found in the soil and the distance from the road contributes to a progressive decrease in contamination intensity. The Pearson’s correlation between the analyzed microelements in soil and wheat indicates that there was only a correlation between Cd content in the wheat and the soil (0.494), indicating that this element entered the wheat from soil. The content of Pb, Hg, As, Zn and Fe in the wheat grain is invariant to their content in the soil samples.