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To systematically study the environmental problems of heavy metal pollution in soils caused by antimony (Sb) smeltery in central and southern China, the pollution levels, sources and risks of heavy metals were explored based on the GIS, pollution indices, multivariate statistical methods combined with positive matrix factorization (PMF) model, and risk assessment model. The results showed the average contents of Hg, Pb, Cd, Cr, As, and Sb in soils were 0.06, 47.77, 2.88, 53.12, 21.22 and 20.53 mg/kg, respectively. Except for Hg and Cr, the contents of other metals all exceeded the background values of Hunan Mountain soil (BV). Spatial distribution of heavy metal contents and pollution indices (Igeo, PLI, and RI) indicated that above 50% of the studied area were polluted moderately by Cd and Sb, and 77% of sampling sites were under a severe ecological risk level. Multivariate statistics and PMF analysis suggested that Cd (76.9%) and As (57.7%) were mainly from agricultural activities, followed by Sb smelting (12.7% for Cd and 25% for As). The atmosphere deposition of transportation and industrial activities, antimony smelting and nature origin respectively contributed 40.6%, 20.5% and 30.7% of Hg in soils. Sb (73.9%) and Pb (54.5%) were from the Sb smelting, followed by the high geological background (35.6% for Pb and 25% for Sb). Cr (69.7%) was natural origin, but agricultural activities had 21.6% of contribution to its accumulation in soils. Significantly, the values of non-carcinogenic risk (HI) for children under three exposure pathways in different soil depths was bigger than 1 and exceeded the "acceptable level" of risk, and the total carcinogenic risks (TCR) for adults and children were exceeded 1 × 10–4 with an unacceptable carcinogenic risk for human body. Oral ingestion of As was the remarkable characteristic of risk, which should be paid attention to. [ABSTRACT FROM AUTHOR]

Antimony pollution in the groundwater of the Xikuangshan (XKS) antimony (Sb) mine area in China's Hunan Province has attracted increasing attention. A total of 43 water samples were collected to help understand the hydrogeochemical characteristics, identify the Sb source, and evaluate the water–rock interactions of the Shetianqiao aquifer (SA). The Sb concentrations in shallow and deep SA water samples were 0.1–47.4 mg L−1 and 0.3–19.2 mg L−1, respectively. Stibnite oxidation and leaching from arsenic alkali residue mine wastes were the main Sb sources for the shallow SA water, whereas stibnite oxidation and stronger water–rock interaction were the predominant Sb sources for the deep SA water. The higher Sb concentration (> 10.0 mg L−1) in shallow SA water was predominantly induced by weathering of Sb-bearing minerals, evaporation/concentration effects, and cation exchange, whereas the higher Sb concentration in deep SA water was largely caused by weathering of Sb-bearing minerals, evaporation/concentration effects, ion exchange, and competitive adsorption. These findings provide a more detailed understanding of the geochemical behavior of Sb in groundwater and can be used to develop suitable Sb pollution management strategies. [ABSTRACT FROM AUTHOR]