Keywords: 
• South Canal /
• heavy metal /
• contamination level /
• potential ecological risk

Abstract: Heavy metals contamination and their impacts on aquatic environment were studied based on eight representative samples collected from water and sediment in South Canal, China. Concentrations of five heavy metals, plumbum (Pb), chromium (Cr), arsenic (As), copper (Cu) and cadmium (Cd) of the samples were analyzed using ICP-MS. The results showed that concentrations of the detected heavy metals from water samples in South Canal were lower than class I values of the National Surface Water Quality Standards. However, for sediment samples, As and Cd concentrations were higher than the corresponding background values of sediment in China, except for Cu, Cr and Pb. Geoaccumulation index evaluation showed that Cu, Cr, Pb were in non-contamination status, while Cd and As fell in the moderate and even severe contamination level in some segments of the river. The monomial potential ecological risk factor (E_rⁱ) showed that the risk potentials of the heavy metals followed an order of Cd > As > Cu > Pb > Cr, ranging from 0 to 355.29. The average value of the Hakanson potential ecological risk (RI) was 128.85, indicating that the potential ecological risk was ‘medium’ in South Canal. In conclusion, this study revealed that Cd and As were at relatively high level and had high ecological risks, and thus should be managed in priority in the South Canal.