a b s t r a c tThe active Panasqueira mine is a tin-tungsten (Sn-W) mineralization hosted by metasediments with quartz veins rich in ferberite. The economic exploitation has been focused on wolframite, cassiterite and chalcopyrite. The mineralization also comprises several sulphides, carbonates and silver sulphosalts. The mining and beneficiation processes produces arsenic-rich mine wastes laid up in huge tailings and open air impoundments that are the main source of pollution in the surrounding area, once the oxidation of sulphides can result in the mobilization and migration of trace metals/metalloids from the mining wastes into the environment, releasing contaminants into the ecosystem.A geochemical survey was undertaken, in order to investigate the environmental contamination impact on agricultural and residential soils in S. Francisco de Assis village due to the mining activities. Rhizosphere samples, vegetables (Solanum tubersum sava and Brassica olerácea L.) which constitute an important part of the local human diet), irrigation waters and road dusts were collected in private residences in S. Francisco de Assis village. According to the Ontario guidelines (Ministry of Environment, 2011), the Arsenic contents in the rhizosphere soils exceed 20 times the reference value for agricultural soils (11 mg kg À1 ). The result obtained showed that some edible plants frequently used in the region could be enriched in these metals/metalloids and may represent a serious hazard if consumed. The potatoes tend to have a preferential accumulation in the leaves and roots while in cabbages most elements have a preferential accumulation in the roots. An index of the risk for residents, due to ingesting of these metals/metalloids, by consuming vegetables grown around the sampling area, was calculated and the result indicates that the inhabitants of S. Francisco de Assis village are probably exposed to some potential health risks through the intake of arsenic, cadmium and also lead via consuming their vegetables.

Selected geochemical results are presented from a study of the Panasqueira mine (Sn-W mineralization), which is one of the Portuguese test sites for the e-EcoRisk project (http://www.e-ecorisk.info/). These data permit a better understanding of the dynamics inherent to leaching, transport, and accumulation of some elements (mainly As, but also Cu, Pb, Zn, and Cd) in different sampling media and their environmental relevance. Stream sediment and water samples were found to be contaminated by the stored waste material in the tailing ponds; this effect could be observed for a considerable distance downstream.

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Panasqueira mine is a tin-tungsten mineralization hosted by metasediments with quartz veins rich in ferberite. The mineralization also comprises wolframite, cassiterite, chalcopyrite, several sulfides, carbonates and silver sulfosalts. The mining and beneficiation processes produce arsenic-rich mine wastes laid up in huge tailings (Barroca Grande and Rio tailings). The contents of As, Cd, Cr, Cu, Pb and Zn were estimated in rhizosphere soils, irrigation waters, road dusts and in potatoes, cabbages, lettuces and beans, collected on local gardens of four neighborhood Panasqueira mine villages: S. Francisco de Assis (SFA) and Barroca suffering the influence of tailings; Unhais-o-Velho and Casegas considered as non-polluted areas. The mean concentrations of metals in rhizosphere soils and vegetables exceed the reference guidelines values and seem to be linked to the sulfides. The rhizosphere ecological risks were ranked in the order of Cd > As > Cu > Pb > Zn > Cr and SFA > Barroca > Casegas > Unhais-o-Velho. Metal concentrations, in vegetables, were found in the order of lettuce > cabbage > potatoes and SFA > Barroca > Casegas > Unhais-o-Velho. For cabbages and lettuces, the tendency of contamination is roots > leaves and for potatoes is roots > leaves > tubers. The risk for residents, due to ingesting of metals/metalloid, by consuming vegetables grown around the sampling area, was calculated and the result indicates that the inhabitants of these villages are probably exposed to some potential health risks through the intake of heavy metals and metalloids via consuming their vegetables.

Road dust resuspension, especially the particulate matter fraction below 10 µm (PM10), is one of the main air quality management challenges in Europe. Road dust samples were collected from representative streets (suburban and urban) of the city of Viana do Castelo, Portugal. PM10 emission factors (mg veh−1 km−1) ranging from 49 (asphalt) to 330 (cobble stone) were estimated by means of the United Stated Environmental Protection Agency method. Two road dust fractions (<0.074 mm and from 0.0074 to 1 mm) were characterised for their geochemical, mineralogical and morphological properties. In urban streets, road dusts reveal the contribution from traffic emissions, with higher concentrations of, for example, Cu, Zn and Pb. In the suburban area, agriculture practices likely contributed to As concentrations of 180 mg kg−1 in the finest road dust fraction. Samples are primarily composed of quartz, but also of muscovite, albite, kaolinite, microcline, Fe-enstatite, graphite and amorphous content. Particle morphology clearly shows the link with natural and traffic related materials, with well-formed minerals and irregular aggregates. The hazard quotient suggests a probability to induce non-carcinogenic adverse health effects in children by ingestion of Zr. Arsenic in the suburban street represents a human health risk of 1.58 × 10−4.

a b s t r a c tThe Panasqueira hydrothermal mineralization, located in central Portugal, is the biggest Sn-W deposit of the Western Europe. The main evidences of the mining exploitation and ore treatment operations are testified with huge tailings, mainly, in the Rio and Barroca Grande areas. The mining and beneficiation processes, at the site, produces metal rich mine wastes. Oxidation of sulfides tailings and flow from open impoundments are responsible for the mobilization and migration of metals from the mine wastes into the environment. Acid mine drainage (AMD) discharged from Rio tailing has a pH around 3 and high metal concentrations. In Zêzere river, Fe and As are the most rapidly depleted downstream from AMD once As adsorbs, coprecipitate and form compounds with iron oxyhydroxides. The Zêzere river waters are oversaturated with respect to kaolinite and goethite and ferrihydrite can precipitate on stream with a near-neutral pH. At sites having low pH the dissolved Fe species in the water, mainly, occur as sulfate complexes due to a high SO 4 concentration. Melanterite (Fe 2+ (SO 4 )Á7(H 2 O)) and minor amounts of rozenite (Fe 2+ (SO 4 )Á4(H 2 O)) and szomolnokite (Fe 2+ (SO 4 )Á(H 2 O)) were observed on Rio tailing basement.

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