In past decades, nano zero-valent iron (nZVI) has been proven to be a promising approach for remediation of contaminated soils. A greenhouse study was conducted to evaluate the effect of nZVI on promoting plant growth and micronutrients uptake, reducing Cr availability in soil and rhizosphere as well as the accumulation and translocation of Cr in lettuce plant. The experiment was arranged in a randomized complete design in factorial manner with three replications. The treatments consisted of three levels of Cr (0, 25, and 50 mg kg−1) and three levels of nZVI (0, 5, and 10%). The results showed that the diethylene triaminepentacetic acid (DTPA)-extractable Cr in the soil and rhizosphere soil decreased significantly with increasing nZVI levels. The nZVI application significantly enhanced the leaves, stems and roots biomass as well as Fe, Mn, Zn, and Cu concentrations of leaves, whereas it reduced the Cr concentrations of plant tissues, bioaccumulation and translocation factor. These finding indicated that the applied nZVI levels did not exhibit inhibitory impact on the normal growth of plant but were effective in enhancing plant biomass and minimizing the Cr accumulation and translocation from the root to the edible parts of the lettuce plants.

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