Concentration and distribution characteristic of main toxic metals in suspended particle material in Nanjing reach, Changjiang River.

Six stations in the lower reach region of Changjiang River within Baguazhou Island, Nanjing reach were chosen to investigate the toxic metals pollution characteristic in suspended particle material (SPM). SPM concentration, as well as reflectance spectroscopy characteristic, toxic metal concentrations, and lead isotopes of suspended particle material were studied. SPM concentrations were obtained from fluvial cross-sectional sampling near the surface (20 cm) and the study presents the cross-sectional averages. SPM concentrations varied around 170-300 mg L(-1). Reflectance spectroscopy measurements differed from each other over each cross-section but no common pattern characterizing the cross-sectional behavior of the measurements was observed. The metal concentrations in the SPM decreased in the sequence: Mn>Zn>Cu>Cr>Pb>Cd. The result of lead isotopes analysis proved that lead isotopes composition in SPM are mainly produced by natural contributions and influenced by anthropogenic activity at the same time.