Contamination, toxicity and speciation of heavy metals in Dongbao River are examined.
The sediment is seriously contaminated with Cr, Cu and Ni which pose acute toxicity.
Dominance of non-residual fractions indicates high mobility of Cd, Cu, Ni and Zn.
The dispersal of heavy metals causes contamination in the non-industrialized areas.
Given the vertical profiles, management efforts on the point sources are inadequate.