Distribution of Heavy Metals in Rice Plant Cultivated in Industrial Effluent Receiving Soil

Heavy metals can have a serious impact if released into the environment even in trace quantities. These can enter into the food chain from aquatic and agricultural ecosystems and threaten human health indirectly. Dhalai Beel produces rice with DEPZ (Dhaka Export Processing Zone) effluent fed water. A field experiment was carried out to investigate the uptake of heavy metals by paddy crop using Thermal Neutron Activation Analysis (TNAA). Rice plants were divided into root, stem, leaf, husk and unpolished rice grain. The distribution of heavy metals in the different parts was investigated. The order of average contents of metals in rice was Zn > Rb > Se > Sc > Cr >Cs. The concentrations were Se 1.92–7.78 ppm, Cr BDL (Below Detection Limit) - 0.74 ppm, Sc 0.01–0.04 ppm, Rb 2.25–16.1 ppm, Fe–BDL, Zn 62.7–102.5 ppm and Co–BDL. Highest TF (Transfer Factor) value is obtained for Fe which is 0.24 and the lowest TF value is for Sc which is 0.02. The concentrations are within acceptable limits.