Diacomanolis, V, Ng, JC, Sadler, R, Nomura, M, Harris, H & Noller, BN 2008, 'Assessment of Cadmium as a Contaminant in Mine Closure', in AB Fourie, M Tibbett, I Weiersbye & P Dye (eds), Mine Closure 2008: Proceedings of the Third International Seminar on Mine Closure, Australian Centre for Geomechanics, Perth, pp. 681-688, https://doi.org/10.36487/ACG_repo/852_63 (https://papers.acg.uwa.edu.au/p/852_63_Diacomanolis/) Abstract: Contamination of soil and water by cadmium from both mine residues, and the use of phosphate fertilizers applied during mine rehabilitation activities, can result in bioaccumulation by terrestrial and aquatic plants and animals, which in turn can lead to human uptake of this element. X-ray absorption spectroscopy, using absorption near-edge spectroscopy-XANES at the K-edges of cadmium, was used to study the molecular form of cadmium present in mine wastes, and determine its association with bioavailability using rat uptake experiments. The XANES spectra were recorded for rat liver samples following dosing with solutions of mine wastes, and mine waste material itself, and compared with Emax values for cadmium model compounds. XANES spectra of mine wastes show that cadmium has features of Cd-S, Cd-O or a mixture of both forms. The results from the rat experiments show that cadmium uptake occurs from CdCl2 solutions, but is negligible from insoluble forms such as CdS commonly found in mine wastes. Bioaccessibility measured using the physiologically-based extraction test (PBET) shows that Cd in mine wastes is likely to be available during both the stomach and intestinal phases of the GI system, and is a more practical way to estimate bioavailability. The information about Cd for mined land that are based on the measure of bioavailability of mine soils using bioaccessibility can be used in a risk assessment framework to develop site-specific health investigation levels for Cd.