EVALUATION OF HEAVY METALS IN SOIL AND VEGETABLES AND THEIR CORRELATION WITH PROPERTIES OF DIFFERENT SOILS

The aim of present study was to determine the heavy metals (HMs) in soils and vegetables irrigated with fresh and contaminated water. Single extraction methods using CaCl2, ethylenetriaminetetraacetic acid (EDTA), CH3COOH and water as extractant were used to assess HMs labile fraction in soil for vegetables. The levels of HMs extracted by understudied extractions ranged from 0.015-1.05, 0.014-8.80, 0.036-3.70, 0.222-4.80, 0.383-5.12, 0.357-3.47 and 1.26-34.0 mg kg-1 for As, Cd, Cr, Cu, Ni, Pb and Zn, respectively. The correlation analysis indicated that a significant correlation (As: r=0.758; Cd: r=0.998; Cr: r=0.914; Cu: r=0.850; Ni: r= 0.832; Pb: r=0.615 and Zn: r=0.881) between the CaCl2-extractable HMs in soil solution with HMs contents in Okra. The organic matter (OM), soil pH, and cation exchange capacity (CEC) can alter the phytoavailability of understudied HMs. The phytoavailability of HMs have a strong correlation with the extractable fraction by CaCl2, total elemental concentration in soils and other physical parameters of soil (OM, pH and CEC). A strong correlation was obtained for water extractable HMs with okra, sponge gourd, brinal, bitter gourd, indian squash, spinach, pepper mint and bottle gourd (p<0.05).