Fig. 1. Concentrations of Pb, Cd, and Zn in leaves of Chinese cabbage grown on contaminated soil in response to different EDTA (black) and EDDS (white) addition: 3 mmol kg^-1 single dose addition (3S), 5 mmol kg^-1 single dose addition (5S), 5 mmol kg^-1 weekly additions (5W), 10 mmol kg^-1 single dose addition (10S), 10 mmol kg^-1 weekly additions (10W), and control soil with no EDTA addition. Means of five replicates are presented; error bars represent standard deviation. Statistically different treatments according to the Tukey test are labeled with different letters.