The aim of study was to assess some heavy metals’ bioaccumulation in lemon balm and assess the risks involved. Pot experiments were conducted on lemon balm (Melissa officinalis L.) irrigated with industrial wastewater. The concentrations of Ni, Pb, Cd and Zn in the soil for all treatments were higher than root and aerial parts of the plant. In all treatments, Ni, Pb and Zn decreased-i.e soil >> root > stem > leaf > seed. Bioaccumulation factor for Ni, Pb, Cd and Zn were less than transfer factors among root, stem, leaf and seed of the plant, stressing on the high concentration of the metals in the soil compared to other organs. The absence of Cd in the plant leaves indicated that lemon balm was a suitable crop for contaminated soils, especially with Cd. The studied wastewater should not comprise more than 25 % of water used for agricultural purposes
