Pb uptake by quail grass (Celosia argentea) grown on Pb – acid battery soil treated with starch stabilized zero-valent iron nanoparticles.

Abstract

The effect of zero-valent iron nanoparticles (nZVI) on the physiology and uptake of heavy metals and nutrients in plants is crucial in the development of nanotechnology for the reclamation of contaminated soils. Zerovalent iron nanoparticles are able to immobilize heavy metals thereby reducing its bioavailability. Plant uptake experiment was thus used to evaluate the immobilizing potentials of starch stabilized zerovalent iron nanoparticles (S-nZVI) in the uptake of Pb by Celosia argentea grown on Pb-acid battery contaminated soil. Application of 1000 mg/kg of S-nZVI to the parent soil reduced bioavailable Pb in Celosia argentea (Quail grass). Celosia argentea grown on the starch stabilized zerovalent iron nanoparticles soil showed better tolerance to Pb than that grown on the parent soil. This was ascertained by the higher shoot and root biomass (dry weight matter). The concentration of iron was found to be higher in the shoots of Celosia argentea grown on the parent soil than for the treated soil. The higher translocation factor (TF) for iron in Celosia argentea (Quail grass) grown on the untreated soil might be one of the factors responsible for the observed trend. The TF for Pb was greater than one, an indication that Celosia argentea could be used in phytoremediation. The result from the pot experiment showed that S-nZVI significantly reduced phytoavavilable Pb.

Key words: Heavy metals; starch stabilized zero-valent iron nanoparticles; Celosia argentea; Phytoremediation