Bioremediation of Heavy Metal Pollution by Nano-Particles of Noaea Mucronata

Abstract

Environmental pollution with heavy metals is a common problem in many countries. Great efforts have been made in the last two decades to reduce pollution sources and remedy the polluted soil and water resources. A field study was conducted in a dried waste pool of a Lead mine in Zanjan (Iran) to find the native accumulator plant(s). Concentrations of heavy metals were determined both in the soil and the plants that were grown in a dried waste pool by using flame atomic absorption method. The concentration of total Cu, Zn, Pb and Ni were found to be higher than that natural soil and the toxic levels. The results showed that six dominant vegetation namely Centaurea virgata, Gundelia tournefortii, Scariola orientalis, Rreseda lutea, Noaea mucronata and Eleagnum angustifolia accumulated heavy metals. Based on the results, it was concluded that Noaea mucronata belonging to Chenopodiaceae is the best Pb accumulator and also a good accumulator for Zn, Cu and Ni, but the best Fe accumulator is Reseda lutea and the best one for Cd is Marrobium vulgare. The bioaccumulation ability of nano-particles prepared from N. mucronata was evaluated in experimental water containers. The study showed that the amount of heavy metals in polluted water decreased several times during three days bioremediation. Based on the obtained data, N. mucronata is an effective accumulator plant and its nano-particles are useful for watery media detoxification and bioremediation in critical conditions.