AN ESTIMATION OF THE TRANSFER OF MICRONUTRIENT (Cu, Mn, Zn) AND TOXIC ELEMENTS (Cd, Cr, Ni, Pb) FROM SOIL TO RICE (ORYZA SATIVA) IN EVROS-ERGENE RIVER BASIN

摘要

In this study, various concentrations of nonessential toxic heavy metals (Cd, Cr, Ni and Pb) and the micronutrients (Cu, Zn, Mn) in twenty brown rice (O.sativa) and relevant paddy soil samples were investigated. The soil and brown rice samples from Evros-Ergene river basin were extracted for their total heavy metals content by dry digestion method and then determined by using ICP OES. The results of this study reveal that the concentrations of Cd, Cr and Ni in the soil of the studied sites are above the maximum permissible levels. The average concentration of all metals in brown rice samples is below the maximum permissible levels of the WHO guideline. The ranking order of bioaccumulation factor (BAF) for heavy metals is Zn > Cu > Mn > Ni> Cr = Cd = Pb, which indicaties that the accumulation of micronutrients was more than that of nonessential toxic heavy metals. It can be concluded that these rice samples cannot be regarded as a complete source to determine all metals posing threat to human health.