title: Understanding the paradox of selenium contamination in mercury mining areas: high soil content and low accumulation in rice.
abstract: Rice is an important source of Se for billions of people throughout the world. The Wanshan area can be categorized as a seleniferous region due to its high soil Se content, but the Se content in the rice in Wanshan is much lower than that from typical seleniferous regions with an equivalent soil Se level. To investigate why the Se bioaccumulation in Wanshan is low, we measured the soil Se speciation using a sequential partial dissolution technique. The results demonstrated that the bioavailable species only accounted for a small proportion of the total Se in the soils from Wanshan, a much lower quantity than that found in the seleniferous regions. The potential mechanisms may be associated with the existence of Hg contamination, which is likely related to the formation of an inert Hg-Se insoluble precipitate in soils in Wanshan.
authors: State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, 46 Guanshui Road, Guiyang 550002, China; Norwegian Institute for Water Research (NIVA), Gaustadalléen 21, 0349 Oslo, Norway.
authors: Hua
authors: H
authors: Zhang
authors: State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, 46 Guanshui Road, Guiyang 550002, China. Electronic address: fengxinbin@vip.skleg.cn.
authors: Xinbin
authors: X
authors: Feng
authors: Academy of Engineering Institute, China University of Geosciences, Wuhan 430074, China.
authors: Chengxin
authors: C
authors: Jiang
authors: Key Laboratory for Information System of Mountainous Area and Protection of Ecological Environment of Guizhou Province, Guizhou Normal University, Guiyang 550001, China.
authors: Qiuhua
authors: Q
authors: Li
authors: Guizhou Academy of Geological Survey, Guiyang 55005, China.
authors: Yi
authors: Y
authors: Liu
authors: State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, 46 Guanshui Road, Guiyang 550002, China.
authors: Chunhao
authors: C
authors: Gu
authors: State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, 46 Guanshui Road, Guiyang 550002, China.
authors: Lihai
authors: L
authors: Shang
authors: State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, 46 Guanshui Road, Guiyang 550002, China.
authors: Ping
authors: P
authors: Li
authors: Norwegian Institute for Water Research (NIVA), Gaustadalléen 21, 0349 Oslo, Norway.
authors: Yan
authors: Y
authors: Lin
authors: Norwegian Institute for Water Research (NIVA), Gaustadalléen 21, 0349 Oslo, Norway.
authors: Thorjørn
authors: T
authors: Larssen
mesh_terms: D004784:Environmental Monitoring; D008628:Mercury / Q000032:analysis* / Q000737:chemistry; D008906:Mining; D012275:Oryza / Q000737:chemistry*; D012643:Selenium / Q000032:analysis* / Q000737:chemistry; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis* / Q000737:chemistry
chemical_list: D012987:Soil; D012989:Soil Pollutants; D008628:Mercury; D012643:Selenium
keywords: Bioaccumulation; Food consumption; Mercury mining areas; Sequential partial dissolution; Soil selenium contamination