Levels of Some Metal Contents in the Soil and Leafy Vegetables Collected From Al-Qanat Highway/ Baghdad City

Abstract

The aim of the present study is to estimate the levels of some essential and non-essential metals content of soil and seven leafy vegetable species, in the field 30m away from the Al-Qanat highway in Baghdad using X-ray fluorescence analysis. The results showed that soil and leafy vegetables had higher levels of macro elements, and that Ca in rocket and purslane was the highest. The average content of trace elements in soil and leafy vegetables has been close to the minimum than the range of permissible limits recommended by WHO and FAO/WHO except Fe, Cr and Ni in soil have exceeded the concentration of the threshold limit (13728.8 mg/kg Dw for Fe, 183.361mg/kg Dw for Cr, and 124.01mg/kg Dw for Ni) value as well for leafy vegetables, the concentration of Fe (573.29 mg/kg Dw in spinach and 540.41 mg/kg Dw in rocket) and zinc (183.52 mg/kg Dw in mallow, and 181.19 mg/kg Dw in purslane) exceeded the permissible limits. The values of As, Cd, Pb and Hg concentrations in soil have been within the range of permissible limits recommended by WHO while in leafy vegetables higher levels of Pb (2.58 mg/kg Dw), and Cd (2.2 mg/kg Dw), were found in the rocket, and fenugreek, respectively. Also, higher levels of Sr were found in the rocket (592.42 mg/kg Dw) and purslane (560.34 mg/kg Dw) as well as Al in spinach (186.55 mg/kg Dw). In addition, P, K, Mg (purslane), Zn (rocket, purslane, mallow), Cd (grapevine, fenugreek), and Sr (rocket, purslane) accumulated the most with the transfer factor (TF) (> 1.0), followed by Ca, Mg, Fe, Co, Cu, Se, Mn, Zn, Ni, As, Cd, Pb, Hg and Sr (0.01–1.0), while Cr, and Al had the lowest accumulation (< 0.01).