Environmental contamination characteristics of heavy metals from abandoned lead–zinc mine tailings in China

Abstract

China holds large-scale lead–zinc mineral resources; however, mining activities often cause severe contamination by heavy metals. This study systemically assessed contamination by eight heavy metals (Cu, Zn, Cd, Pb, Cr, Hg, Ni, and As) in mine tailings, soil, and groundwater from 27 contaminated sites across China. Regarding mine tailings, 1% of the mine tailing samples were hazardous waste and 20% were class II non-hazardous waste. Regarding soil, Zn and Pb showed the highest mean concentrations, at 5574.67 mg/kg and 2034.88 mg/kg, respectively. The indexes of geo-accumulation (Igeo) of eight heavy metals ranged from −3.62 to 7.67, while Zn, Pb, and Cd showed the highest environmental risk levels as the priority pollutants. The contamination levels of these heavy metals in groundwater were generally in the order of Zn>As>Pb>Ni>Cd>Cu>Hg>Cr. In this study, 20% of the soil and 10% of the groundwater samples exceeded the corresponding quality limits. The content of heavy metals in soil, groundwater, and mine tailing were positively correlated, demonstrating the main pollution source and transport paths. The pollution levels of heavy metals in soil and groundwater were listed in the foremost and moderate positions compared with similar sites from other countries, respectively. These results may help determine the pollution levels of lead–zinc mining regions and direct the remediation activities of target sites to support the environmental management of abandoned mining and tailing waste in China.

Phytoaccumulation of Heavy Metals in South Kazakhstan Soils (Almaty and Turkestan Regions): An Evaluation of Plant-Based Remediation Potential

“…Comparing such severely contaminated soils to baseline values seen in pure environments, studies have shown startling increases in heavy metal contents. According to Han et al [43], studies carried out in the area of abandoned mining sites have revealed lead concentrations that are up to 50 times higher than the allowable limits. Additionally, levels of zinc and cadmium have been found to exceed regulations by factors of 25 and 15, respectively.…”

Electrochemical Detection of Cd2+, Pb2+, Cu2+ and Hg2+ with Sensors Based on Carbonaceous Nanomaterials and Fe3O4 Nanoparticles

“…Heavy metals are those metallic elements with a density greater than 4.5 g·cm −3 , such as Cd, Cr, Hg, Pb, Cu or As, all of which are known to have high toxicity, long half-life and non-biodegradability [ 9 , 10 , 11 ]. These pollutants come mainly from mining and industrial activities, wastes from mining, smelting, metal refining and coal burning operations [ 12 , 13 , 14 ]. When heavy metals enter the environment, they come into direct contact with living organisms and begin to accumulate causing extremely dangerous manifestations such as damage to the digestive, renal, neuronal, cardiovascular, reproductive, visual analyzer systems and even molecular changes in the DNA [ 15 , 16 , 17 , 18 ].…”