The Effect of Application of Industrial Effluent in Irrigation of Rice on Accumulation of Heavy Metals in Soil and the Crop

In order to investigate the effects of application of industrial wastewater on accumulation of heavy metals in soil and cultivated rice, the farms effected by Amol Industrial wastewater Park were selected and samples of irrigation water, soil and also roots, shoots and grains of rice were collected. Then, the amounts of Cr, Cd, Ni and Pb in these samples were determined. The results showed that the amount of these elements in samples of water, soil and rice were increased due to application of wastewater. The total amount of cadmium in the soil in highest amount increased to 29.75% which was higher than the other elements. Available lead in the soil at highest amount was increased to 40% compared to control. Due to using industrial wastewater, increase in the accumulation of heavy metals in studied rice roots were more than that in other organs. Accumulation of the elements in the grain was Cr> Cd ~ Pb> Ni, respectively. Accumulation of Pb in root and shoot of rice were more than other metals. Heavy metals transfer factor from the soil to the shoots was more than grain. Transfer factor for Cd in grain and shoots in site 2 was equal to 1.52 and 1.44, respectively, which were more than other elements. Cadmium risk index was highest among the elements investigated.