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The mobility and bioavailability of As and Sb in relation to soil-biota transfer were evaluated at a former Sb mining and smelting site (Glendinning, SW Scotland, UK). The study specifically assessed the accumulation of As and Sb in different environmental components (soil, plants and earthworms) across mining area to estimate risk factors for the biota. Total concentrations and fractions of As and Sb in soils were determined. The latter using both a single solute and a non-specific stepwise sequential extraction (CISED) method. Mineralogical information was gathered from XRD and SEM analysis used to identify element distribution patterns. Pseudo-total (aqua-regia) levels of As and Sb in the soils varied between 50-17,400 mg kg(-1) and 10-1,200 mg kg(-1), respectively. Both elements are predominantly associated with Fe (or Al) oxides/hydroxides, by adsorption around silicate grains, representing a potentially bioavailable fraction. Antimony was also associated with sulphide phases. The highest values of As and Sb in biota were recorded in the earthworms (960 mg kg(-1) and 27 mg kg(-1), respectively). Bioconcentration factors for both elements were below 1 and the highest for earthworms. Total and leached As levels in soils and biota were positively and significantly correlated, but only for Sb in earthworms and grass. Bioavailability of As in the biota, was shown to be limited by pH. In spite of the considerably high As and Sb contents of the soil the plant contamination remained comparably low, but still exceeded background values.

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Total concentrations and extractable fractionations of As and Sb were determined in soil samples from former mining sites in Scotland and Italy. Pseudo-total levels of As and Sb in the sample were between 50-17,428 mg/kg and 10-1,187 mg/kg (Scotland), and 16-691 mg/kg and 1.63-11.44 mg/kg (Italy). Between 0.001-0.63% and <0.001−8.82% of the total soil As and Sb, were extractable using, a single extraction bioavailability estimate. Data from an As-specific extraction procedure revealed that up to 60% of As was associated to amorphous Fe-Al oxyhydroxide phase in all soils. A non-specificsequential extraction test also showed As to be strongly associated with Fe (and Al) oxyhydroxides at both locations. In the case of Sb, in addition to the crystalline Feoxide bound Sb the Al-silicate phase also appeared to be significant. At both sites Sb appears to be chemically more accessible than As with consistent availability despite the varied origin and host soil properties.

ABSTRACT. In the present study the mineralogy of a tailing dam situated in the Maşca mining area is discussed. Our aim was to point out the physicochemical processes, which occur under the action of the exogenous factors. The studied samples were collected from different levels of the dam wall, from the Maşca mine and Iara river waters. The applied analytical methods are: transmission polarized microscopy, transmission electron microscopy, X-ray diffractometry, and atomic absorption spectrometry. The physicochemical parameters have been measured in situ and in the laboratory.The minerals present in the tailings are represented by: garnets (andraditegrossular and almandine series), diopside, hedenbergite, actinolite, tremolite, epidote, zoisite, biotite, phlogopite, serpentine minerals, chlorite, tourmaline, quartz, feldspar, anatase, apatite and opaque minerals (pyrrhotite, pyrite, magnetite and hematite). The carbonate minerals belonging to the mining waste are represented mostly by dolomite and subordinately by calcite. The identified neoformation minerals formed as a result of the action of the exogenous factors are the following: illite, illite/smectite, nontronite, palygorskite, chlorite-vermiculite, gypsum, epsomite, hexahydrite, wattevillite, ferrohexahydrite, hallotrichite, bilinite(?), goethite and amorphous iron hydroxide.The ) contents, exceeding international and national guidelines. Although the pH of the streams originating from the mine area vary between neutral to slightly alkaline, pollution occurs and significantly impacts the mineralized area as well as the neighboring areas.