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An extensive study on the spatial distribution and source apportionment of heavy metals in soils and so by risk assessment at You'xi County, a major Pb–Zn mining area southeast China, was conducted in this contribution. A total of 93 soil samples were examined with the concentration of heavy metals (As, Cd, Cr, Cu, Hg, Pb, and Zn), pH, and soil organic matter (SOM) contents by using geostatistical approaches combined with geographic information system (GIS) analysis. The mean values of heavy metals were determined to be 7.9 ± 5.8, 12.8 ± 14.1, 80.4 ± 42.0, 34.4 ± 45.0, 0.12 ± 0.13 368.5 ± 873.6, and 369.6 ± 505.5 mg kg − 1 (mean ± SD) for As, Cd, Cr, Cu, Hg, Pb, and Zn, respectively. Contents of all heavy metals present in the study area were considerably higher than their background values of provincial and national standards except for As. A principle component analysis revealed the main origin of heavy metals: soil parent materials for Cu, Pb, and Zn; atmospheric deposition during mining processes for Cr, and Hg; and human farming activities for Cd. Carcinogenic risk was assessed with an average value of 69.3 × 10 − 6 mg kg − 1 , suggesting an average of 69 individuals per million people being predisposed to cancer. Meanwhile, the identification of heavy metal sources in agricultural soils might be beneficial to local soil protection and soil quality improvement. [ABSTRACT FROM AUTHOR]

Source apportionment of fluorine pollution in the regional shallow groundwater at You’xi County, southeast China, has been analyzed by means of monitoring F − ion change characteristics in this area. Meanwhile, pollution sources and influencing factors of the shallow groundwater have been uncovered by studying the correlation between F − and other related ions such as Na + , Ca 2+ , Cl − , NO 3 − , HCO 3 − , as well as (K + + Na + )/Ca 2+ ratio ( R ) and pH effect. The results show that F − ions in shallow groundwater at the study area come mainly from the dissolution of fluorinated minerals in a form of fluorite (CaF 2 ), the so-called water-rock interaction, and there is a higher possibility for the occurrence of fluorine water where the ratio of (K + + Na +) /Ca 2+ exceeds a value of 2.1. Moreover, the release and migration of F − ions have been favored by the alkaline environment in this study area. [ABSTRACT FROM AUTHOR]