In order to investigate the extent and degree of afsenie and heavy metal contamination and the bioavailability of toxic elements around the abandoned mine in Korea, an environmental geochemical survey was indertaken in the Daduk mine. After appropriate preparation, tailings, soil, stream sediments, crop plant and fingermail samples were analysed for As, Cd, Cu, Pb and Zn by ICP-AES and ICP-Ms. Elevated levels of 8.782 ㎎/㎏ As, 8.3 ㎎/㎏ Cd, 489 ㎎/㎏ cu, 3.638 ㎎/㎏ Pb and 919 ㎎/㎏ Zn were found in tailings from the Daduk mine. These significant concentraions can impact on soils and sediments around the tailing ponds. Mean concentraions of As, Cd, Pb, Cu and Zn in soils are significantly higher than those in world average soil, especially for As and Pb. Element concentraions in sediments decrease with distance from the tailing ponds due to a dilution effect by the mixing of unconraminate sedements. Arsenic and Cd are elevated in rice grains and stlks, and Cu and Zn concentraions in chinese cabbage, sesame and bean leaves are higher than the upper limit values for nomal plant. Arsenic concentraion in fingernails of farmers are higher than the normal level with a maximun value of 1.5 ㎎/㎏. The post-ingestion bioavailability of toxic heavy metals in some paddy and farmland soils has been also investigated usinf the SBET (simple bioavailability extract test) method. The method utilises synthetic leaching fluids closely analogous to those of the human stonach. The quantities of As, Cd, Cu, Pb and Zn extracted from paddy soils after 1 hour indicated 15.9, 65.4, 46.2, 39.4 and 29.4% bioavailability, respectively and for farmuland soils, 12.4, 26.0, 31.2, 29.3 and 19.4% bioavailability, respectively. The results of the SBET indicate that regular ingestion of soils by the local population could pose a potential health threat due to long-term toxic element exposure.
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