Heavy metals in the water environment of Yangtze River Economic Belt: Status, fuzzy environmental risk assessment and management

Accompany with many chemical industries and mineral smelting plants, heavy metal pollution in the Yangtze River Economic Belt (YREB) has threatened public health and ecological safety, especially that in water environments. Based on bibliometric analysis and the time weight vector, we reviewed eight heavy metals pollutants in the surface water and sediments. Under good uncertainty control, we analyzed the fuzzy health risk and ecological risk, and the priority control metals and regions were established. Results show that the heavy metal pollution in surface water was light and mainly distributed downstream. Conversely, concentrated in the upstream areas, pollution in surface sediments exceeded the soil background values by more than 60%. The fuzzy total average carcinogenic risk was: As (6.12 x 10(-5)) > Cr (5.42 x 10(-5)) > Cd (3.81 x 10(-5)). The potential ecological risk in Yunnan and Guizhou was over 20 times the Grade IV (600) level, with the highest contribution being from Cd and Hg. Finally, five provinces were established as the priority control regions, and the heavy metal pollution sources were identified as combined pollution, mainly released due to the development and smelting of mineral resources, especially the smelting of nonferrous metals and the discharge of industrial wastewater.

Automated summary

The heavy metal pollution in the Yangtze River Economic Belt has become a serious issue, especially in water environments. While pollution in surface water is relatively light, pollution in sediments exceeds soil background values by more than 60%, posing potential ecological risks.