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4671056 
Journal Article 
High cadmium concentration in soil in the Three Gorges region: Geogenic source and potential bioavailability 
Liu, Y; Xiao, T; Ning, Z; Li, H; Tang, J; Zhou, G 
2013 
1 
Applied Geochemistry
ISSN: 0883-2927
EISSN: 1872-9134 
PERGAMON-ELSEVIER SCIENCE LTD 
OXFORD 
37 
149-156 
WOS:000323940500015 
This study investigated the distribution and sources of Cd in soils from a Cd-rich area in the Three Gorges region, China. The results showed that in the study area arable soils contain 0.42-42 mg kg(-1) Cd with 0.12-8.5 mg kg(-1) in the natural soils, corresponding to high amounts of Cd (0.22-42 mg kg(-1)) in outcropping sedimentary rocks in the area. Both lognormal distribution and enrichment factor (EF) plots were applied in an attempt to distinguish between geogenic and anthropogenic origins of Cd in the local soils. The lognormal distribution plots illustrated that geogenic sources dominated in soils with low and moderate Cd concentrations (<8.5 mg kg(-1)), whereas anthropogenic sources (agricultural activities, coal mining) significantly elevated Cd contents in some arable soils (>8.5 mg kg(-1)). The enrichment factor plots illustrated that the majority of the soil samples had EF values of <5, pointing to a geogenic origin of Cd in the soils, whereas some arable soils had EF values >5, pointing to an additional anthropogenic input of Cd to the soils. Sequential extraction results showed that Cd soluble in water and weak acid (water-soluble, exchangeable and carbonate fraction of the soil) accounts for an average of 31% of the total soil Cd, which indicates high potential for Cd mobility and bioavailability. The findings point to a potential health risk from Cd in areas with high geogenic background concentrations of this metal. (C) 2013 Elsevier Ltd. All rights reserved.