Risk assessment of heavy metals in soil previously irrigated with industrial wastewater in Shenyang, China

The results have highlighted that Cd concentrations in soils still exceed the Environmental Quality Standard for Soil in China (GB15618-1995) grade C standard in SLIII region, and grade B standard in LR. In the SLIII, Zn and Pb concentrations in soil are higher than the grade A standard, although Cu is close the grade A standard. In SLIII the dominant chemical fractions were the exchangeable and carbonatic forms, which represent up to 43% and 35% of the Cd, respectively. The Cd in these two fractionations poses the highest risk for the plant absorption and accumulation. Therefore the SLIII should be abandoned for cultivated crops to prevent the Cd contamination of food chain and any associated hazards to human health.