Ecological risks of some heavy metals in sediment samples collected from downstream of the Red river

Abstract

This study aimed to assess the accumulation of some heavy metals such as Cu, Pb, Cd, and Cr in the sediments collected from downstream of the Red river from the south of Hanoi city to Nam Truc district, Nam Dinh province. Besides, the geological accumulation index (I_geo) and the potential ecological risk index were calculated to understand the impact of heavy metal content in the sediments on the ecosystem. The results showed that the concentration of several metals (Cu, Pb, Cd, Cr) in 20 sediment samples was lower than the permitted values specified in Technical Regulations on sediment quality (QCVN 43:2017/BTNMT). However, according to the Canadian guidelines, the concentrations of metals in 50% of samples had a low level of effect. The potential ecological risk index of metals ranges from 1.8 to 11.6, revealing that the study area has a low-level metal risk. This data can clarify the area's potential risk level and provide the scientific basis for recommending measures to control and reduce sources of metal pollution into the aquatic environment.