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An area affected by the long-term weathering of sphalerite-bearing mine wastes was studied in order to assess the environmental fate and behaviour of different toxic elements occurring in this mineral. Soil and plant samples were collected at different distances from the polluting sources and analysed for the content and distribution of Zn, Cd and Tl. Soils are highly polluted with Zn and Cd, reaching total concentrations up to 92,940 and 218 mg kg − 1 , respectively. Soil contamination with Tl appears slight, with maximum total concentrations of 1.13 mg kg − 1 . Mobile contents of Zn and Cd also reach high values, above 500 and 5 mg kg − 1 , respectively. There is a great risk of an additional mobilization of Zn and Cd under acidic oxidizing conditions, whereas Tl mostly occurs in the residual fraction. Of the plants growing in this area, Jasione montana L. and Orchis maculata L. show a high risk of Cd incorporation in the trophic chain. These plants accumulate Cd concentrations up to 12.6 and 4.50 mg kg − 1 in their aerial parts.

The mobility and phytoavailability of arsenic in an area affected by the abandoned exploitation of an arsenical tungsten–tin deposit was studied to establish the current and eventual environmental risks and to propose possible remediation practices. Soil and plant samples were collected at different distances from the polluting sources and analyzed for their As content and distribution. Critical soil total concentrations of As were found, with values in the range 175–2300 mg kg − 1 . The readily labile As contents represent Agrostis castellana (Boiss. & Reut.), Centaurea jacea L., Eryngium campestre L. and Scirpus holoschoenus L.. Such plants show important root bioaccumulation factor values in relation to the labile As contents (up to 197, 58, 201 and 88, respectively) and low translocation factor values (down to 0.170, 0.032, 0.173 and 0.036, respectively). Additionally to promote the revegetation with these plants, the species Rumex acetosella L. should be eliminated as this behaves as an index plant, reaching above-ground As concentrations up to 218 mg kg − 1 .