Thallium occurrence and partitioning in soils and sediments affected by mining activities in Madrid province (Spain)

Abstract

Thallium (Tl) and its compounds are toxic to biota even at low concentrations but little is known about Tl concentration and speciation in soils. An understanding of the source, mobility, and dispersion of Tl is necessary to evaluate the environmental impact of Tl pollution cases. In this paper, we examine the Tl source and dispersion in two areas affected by abandoned mine facilities whose residues remain dumped on-site affecting to soils and sediments of natural water courses near Madrid city (Spain). Total Tl contents and partitioning in soil solid phases as determined by means of a sequential extraction procedure were also examined in soils along the riverbeds of an ephemeral and a permanent streams collecting water runoff and drainage from the mines wastes. Lastly, electronic microscopy and cathodoluminescence probe are used as a suitable technique for Tl elemental detection on thallium-bearing phases. Tl was found mainly bound to quartz and alumino-phyllosilicates in both rocks and examined soils. Besides, Tl was also frequently found associated to organic particles and diatom frustules in all samples from both mine scenarios. These biogenic silicates may regulate the transfer of Tl into the soil-water system.

Thallium (Tl) sorption onto illite and smectite: Implications for Tl mobility in the environment

“…Moreover, it seems thallium goes preferentially on illite clays instead of smectite (Voegelin et al, 2015) which is in accordance with the lower Tl affinity evidenced in this study. However, in many studies where sequential extractions are used, thallium associated to aluminosilicates is always assimilated to the residual fractions without exchange capacity (Vaněk et al, 2009(Vaněk et al, , 2013Gomez-Gonzalez et al, 2015). It is assumed that thallium is either in primary minerals such as micas or feldspar for instance (Vaněk et al, 2009;Gomez-Gonzalez et al, 2015) or substituted to K in illite interlayer space (Jacobson et al, 2005b;Vaněk et al, 2013;Voegelin et al, 2015).…”

Thallium contamination in agricultural soils and associated potential remediation via biochar utilization

“…The similarity of the metallic and covalent radii of Tl to that of lead (Pb) implies their similar behavioral patterns in the aquatic system (USEPA 1979). In freshwater, Tl can form complexes with inorganic and organic ligands through its oxidation of Tl(I) to Tl(III) by biological process (Scheckel et al 2004) and yet the ionic form of Tl(III) species can be the most abundant form in water resources (Gomez-Gonzalez et al 2015). However, with properties similar to that of potassium (K), Tl + can form even more stable compounds, while Tl 3+ can behave as a strong oxidant similar to aluminum (Al).…”

Assessing the Source of Thallium Contamination in Ground and Surface Waters in the Locality of Yamtenga (Burkina-Faso): Correlation with Some Heavy Metal Ions

“…Other studies reported thallium concentrations in the order of 10 ppm in soils developing on sulphide-rich mineralization [16,17]. Anthropogenic sources of thallium are related to mining activities, either by the release of atmospheric thallium by smelters [18,19,20,21], or by developing on mining waste [22,23], with concentrations which might exceed 200 ppm. The permissible content in uncontaminated soils is 1 mg. kg [16,24].…”