Risk Assessment of Heavy Metal Contamination in Paddy Soil, Plants, and Grains (Oryza sativa L.)

Abstract

Heavy metals are accumulated in plants and they affect human health. This study is made to assess the effect of agrochemicals used in paddy fields on human health. The heavy metals used in agrochemicals get accumulated in different parts of paddy plant (Oryza sativa L.). The toxic heavy metals (Cd, Cr, and Pb) and the micronutrients (Cu, Mn, and Zn) are estimated in the paddy field soil and plants. Mn and Cd are accumulated more in shoot than in root. The metal transfer factors from soil to rice plant are significant for Pb, Cd, Cu, Cr, Mn, and Zn. The ranking order of bioaccumulation factor (BAF) for heavy metals was Zn > Mn > Cd > Cu > Cr > Pb which indicates that the accumulation of micronutrients was more than that of toxic heavy metals. The concentrations of heavy metals were found to be higher in paddy field soils. Organic agriculture with little use of agrochemicals could be the alternative solution for reducing the contamination of toxic heavy metals particularly the toxic Cd, Cr, and Pb in the paddy fields producing rice.