Eight heavy metals (As, Cd, Cr, Cu, Ni, Pb, Zn, and Hg) in the soils from 53 reclaimed industrial sites and 23 river sediments in the Shanghai suburbs were determined using the Nemero pollution index and Hakanson potential ecological risk index (RI). The results show that the eight heavy metals exceed the secondary standard limits to different extents. The rate of standard excess is the most prominent for Cu and Zn; it accounts for 47.17% and 43.40%, respectively. The contents of heavy metals in the sediments from surrounding rivers are significantly lower than those in soil from reclaimed industrial sites. The comprehensive Nemero pollution index of heavy metals in reclaimed soil is 11.41, which represents a serious pollution level; Cu and Zn are the most prominent heavy metals. The Nemero pollution index of heavy metals in surrounding river sediments is 1.26, indicating slight pollution. Based on the single-potential ecological risk, the heavy metals at the reclaimed industrial sites all have a slightly latent ecological risk level, except for Cd (strong), Hg (strong), and Cu (moderate). The potential ecological RI is high (385.79). Heavy metals from the surrounding river sediments have a mild potential ecological risk level, except for Hg. Overall, the potential ecological level is mild (RI=83.91). In short, Cu and Zn are more prominent in reclaimed industrial soil. With respect to the toxic response factor, Cd and Hg should be focused on. The heavy metal pollution of surrounding river sediments is light, leading to a mild potential ecological risk level.
Keywords: Nemero index; heavy metals; potential ecological risk index; reclaimed industrial sites; sediments; soil.