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ABSTRACT This paper presents the interdisciplinary investigation (archaeology, geochemistry, history) of a medieval silver and lead production site located in southern France, in the Minier valley (Occitanie, Aveyron, Le‐Viala‐du‐Tarn). In order to identify the production sites, in situ geochemical surveys were carried out using a portable X‐ray fluorescence spectrometer and differential GPS, guided on the analysis of medieval archival sources. The cartographic representation of the metal concentrations in the surface horizons shows significant enrichment of zinc and lead in the vicinity of the mines. This first type of enrichment makes it possible to highlight the activities of separation of sphalerite and silver‐bearing galena. The galena thus isolated on the hillsides is then transported to the vicinity of watercourses, where it is crushed, washed, and smelted. These secondary activities result in a last type of enrichment in which only lead is found in large quantities. The cross‐referencing of the information made it possible to overcome the challenges related to the location of the mineral processing workshops, which were often invisible on the surface. The medieval workshops have been located and a function suggested, outlining the first trends in the spatial and social division of labour and providing a solid corpus for future archaeological excavations. Finally, this study highlights the persistence of significant metal contamination in the soils of a rural valley and encourages the consideration of former mining areas when examining the environmental impact of metal production. [ABSTRACT FROM AUTHOR]

Ground control is multi-tasking and continuous process for the stability of underground openings. Balya underground lead and zinc mine is an important case study area due to its deepest working condition and the highest production amount among Turkish underground metalliferous mines. Mining-induced seismicity needs to be investigated especially for deep as well as tectonically active mine sites. Increasing depth will increase the stress around an underground opening that is a key factor of rock-burst hazard. Rock burst potential can be estimated from analytical approaches based on the relation between rock mass strength and stress around openings; however, one of the best way is to monitor the mining-induced seismicity. The support system is designed based on the actual geotechnical conditions determined from the excavated working face prior to support applications in the mine. Empirical methods are then used to make a decision about the support system. If the location is designated as a seismically active region based on micro-seismic event results, support components are selected as a dynamic support system that must absorb the energy released from the surrounding rock masses. The purpose of this study is to investigate seismically active locations according to mining-induced seismicity and the support system design principles for that locations to protect the openings against seismic loads. [ABSTRACT FROM AUTHOR]

In November 2016, the total metal concentrations in nine representative locations in lead (Pb)-zinc (Zn) mining areas, located in Guangdong Province, South China, were determined experimentally by flame atomic absorption spectrometer. The results indicated that the paddy soils were heavily contaminated with Cd (20.25 mg kg), Pb (1093.03 mg kg), and Zn (867.0 mg kg), exceeding their corresponding soil quality standard values and background values. According to the results, the mean enrichment factor levels of the studied metals decreased in the following order: Cd > Zn > Pb > Cu > Ni > Mn > Cr. Among these metals, Cd, Pb, and Zn were predominantly influenced by widespread anthropogenic activities. The highest concentrations of the studied metal pollutants were distributed in the areas surrounding the mining activity district. Multivariate statistical analysis indicated that the major contributing sources of the studied metals were metal ore mining, smelting, and processing activities. However, the composition of soil background was another potential source. Moreover, the assessment results of environment risks showed that the potential ecological risks, in decreasing order, were Cd > Pb > Zn > Cu > Ni > Cr > Mn. Additionally, the non-carcinogenic risk represented the trend of HI > HI > HI > HI , and the carcinogenic risk ranked as CR > CR > CR . Among the environmental risk substances, Cd and Pb were the main contributors that pose ecological harm and health hazards through their serious pollution. Consequently, greater attention should be paid to this situation. [ABSTRACT FROM AUTHOR]

Aliva has been the most productive Zn-Pb mine in the Picos de Europa Mississippi Valley-type (MVT) district of Spain's Cantabrian Zone. The mineralisation is hosted in a Variscan thrust sheet by strata of the Late Carboniferous (~309 ± 3 Ma) Picos de Europa limestone-shale formation. Paleomagnetic and rock magnetic analyses of 194 specimens from 23 sites show that the sphalerite-galena-dolomite ore carries a stable characteristic remanent magnetisation (ChRM) in magnetite-titanomagnetite with minor pyrrhotite. Uncorrected for bedding tilt, the ChRM's direction is declination ( D) = 347.2°, inclination ( I) = 61.8° ( N = 20 sites, k = 75.4, α = 4.3°). A negative paleomagnetic fold test shows that the MVT mineralisation is in one or more carbonate olistoliths of the Picos de Europa Formation in shales of the overlying Late Carboniferous Lebeña Formation and that the ChRM entirely postdates Variscan orogenic deformation. No plausible tilt correction of the ChRM's paleopole supports a previously proposed late Variscan (Permian-Triassic) age for the genesis of the MVT mineralisation at Aliva. The paleopole does support an age of 112 ± 8 Ma for the hydrothermal dolomitisation and MVT mineralisation event with a subsequent increase in bedding tilt by ~10° NNE during the Oligocene-Miocene Pyrenean (Alpine) Orogeny. The 112 ± 8 Ma Aptian-Albian age ties ore genesis to the 35° ± 2 counterclockwise rotation of the Iberian peninsula relative to stable Europe and strongly favours an origin in the rift's flank associated with rift hydrothermal activity. [ABSTRACT FROM AUTHOR]

Concentrates of zinc and lead are primary raw materials in the pyrometallurgical process (Imperial Smelting Process) of lead and zinc production. During the studies it was found that Zn (sphalerite) and Pb (galena) sulphides were the main minerals in the raw material. The examined samples, taken from particular technological sections showed presence of galena. After detailed chemical studies it was found that this mineral showed high variation of concentration of accompanying elements, such as: Ca, Mn, Cu, As, Se, Ag, Cd, Sn, Sb. The results of these studies may make, in addition to providing a better understanding of accompanying elements circulation in the ISP technological process, a valuable contribution to the identification of the forms of occurrence of the accompanying elements in the various technological wastes. The form of elements occurrence in wastes is the basic factor in the development of optimal metals recovery method. [ABSTRACT FROM AUTHOR]

We assessed the quality of plant communities across a range of lead (Pb) and zinc (Zn) soil concentrations at a variety of sites associated with Pb mining in southeast Missouri, USA. In a novel application, two standard floristic quality measures, Mean Coefficient of Conservatism (Mean C) and Floristic Quality Index (FQI), were examined in relation to concentrations of Pb and Zn, soil nutrients, and other soil characteristics. Nonmetric Multidimensional Scaling and Regression Tree Analyses identified soil Pb and Zn concentrations as primary explanatory variables for plant community composition and indicated negative relationships between soil metals concentrations and both Mean C and FQI. Univariate regression also demonstrated significant negative relationships between metals concentrations and floristic quality. The negative effects of metals in native soils with otherwise relatively undisturbed conditions indicate that elevated soil metals concentrations adversely affect native floristic quality where no other human disturbance is evident. [Copyright &y& Elsevier]

Abstract: Galena has been mined in Bellmunt (Priorat, Western Mediterranean Area) since ancient times until 1972. While sediment pollution originated by the mining activity in the Ebro River passing the region has been investigated to some extent, the local impact on soils and plants has received poor attention. Here we report first results on the concentrations of major metal contaminants and antimony in soils and representative plants from four selected sites with different pollutant burdens around the mining area. Total (HNO3, HF digest) soil concentrations were analysed. Soils had alkaline pH (8.0±0.2), organic matter contents ranging from 8 to 24gkg−1, and a sandy-loam or a loamy-sand texture. Present study highlighted that metal accumulation in different plants varied with species, tissues and metals. All analysed plant species showed enhanced root and shoot concentrations of Cu, Pb, Zn, and Sb when growing on the more polluted soils and all, but one, restricted the translocation of metals from roots to shoots exhibiting shoot/root concentration ratios lower or close to unity. A notably exception was Moricandia moricandioides (Boiss.) Heyw. [M. ramburii Webb] where shoot/root Zn concentration ratios up 5.5 were observed. This metal accumulation pattern was only observed for Zn and not for other analysed metal contaminants. The concentrations of other, poorly mobile metals, like Pb or Cu were always higher in roots than in shoots (e.g. Pb shoot/root ratios ranged from 0.13 to 0.24). Taking into account the high Pb burden of the soil samples and these low shoot/root Pb ratios, it can be excluded that the particular Zn accumulation pattern of M. moricandioides was biased by soil contamination of shoot samples. To our best knowledge this is the first report of Zn accumulation behaviour in a Moricandia species. The soil-to-shoot transfer factors (SAF) for this species were, however, relatively low ranging from 0.2 to 1.3. Further studies are required to confirm the possible Zn-accumulator character of M. moricandioides. [Copyright &y& Elsevier]

Abstract: Eleven composite soil samples, developed either on schist materials or fine heterogeneous waste materials and coarse metallurgical slags, were collected in the Braçal (Portugal) abandoned lead mine. Plants growing in each sampling area were identified. A total of 49 plant samples of eight species –Acacia dealbata Link, Acacia melanoxilon R. Br., Cistus inflatus Pourr. ex Demoly, Erica arborea L., Eucalyptus globulus Labill., Pinus pinaster Aiton, Quercus robur L., and Ulex minor Roth – were collected. This study intends to evaluate the available fraction of aluminium, lead, manganese, and zinc in the soils using dry and moist samples in contact with five extractant solutions, degasified distilled water, and calcium chloride, calcium nitrate, ammonium acetate and DTPA aqueous solutions, and to compare together these results with the total elemental amounts in the aboveground part of the plant species. The available fraction is higher in moist than in the dry soil samples. The correlations between the soil available fraction of the elements and its concentration in the plants suggest that DTPA is not the best extractant for lead bioavailability evaluation. Variable results were observed for the bioavailable fraction of the elements evaluation suggesting that, in multielemental contaminated soils, calcium chloride seems to be a good extractant medium, once it correlates with the higher number of plant species. [Copyright &y& Elsevier]

Abstract: Mining activities provide a good source of minerals of different nature. On the one hand, the primary minerals for whose formation a geological time-scale is required. On the other hand, secondary minerals, formed from removed products after the earlier weathering and alteration states. These are characteristic of the local geology and the environment context that commonly appears due to the low chemical stability of their original primary minerals. This work shows how quickly the reactions promoting secondary minerals may have taken place, due to the fact that these were found in newly formed solid materials called efflorescences. To achieve this purpose, the sampling is crucial. It was carried out in such a way that tried to guarantee that the samples collected consisted in the very top soil matter (first 2cm depth). Thus, unlike the deeper soil, the material analysed may have been newly formed due to the interactions that they had with the place weathering agents (i.e. air oxygen, humidity, and microbial activities). Raman spectroscopy has emerged as a good and fast non-destructive technique that provides molecular information of the local mineralogy without the need of any pre-treatment of the samples. At the same time, the work looked for information on the variety of non-stable lead and-or zinc containing minerals due to the possible health and environmental risks they convey. Among the different minerals identified, 16 were of primary nature while 23 may be classified as secondary minerals, probably formed in the last decades as the result of the extractive activities. [Copyright &y& Elsevier]

Abstract: Contamination by lead (Pb) and zinc (Zn) was studied in seawater, sediments, seaweeds and blue mussels near the former Black Angel Pb–Zn Mine in Maarmorilik, West Greenland. The mine operated during the period 1973–90 when mine waste (tailings and later waste rock) was discharged directly into the sea. Metal concentrations peaked during the mining period and Pb and Zn in seawater within the discharge area were measured up to 440 and 790 μg L−1, respectively. Pb in fiord sediments, seaweeds and blue mussels just outside the discharge area were measured in concentrations up to 190, 84 and 2650 and Zn up to 300, 360 and 1190 μg g−1 dry wt., respectively. Within the discharge area, seawater metal concentrations (especially Pb) decreased abruptly after mine closure. Metals concentrations in sediments and biota, however, decreased more slowly and two decades after mine closure seaweeds and blue mussels were still contaminated 12 km from the mine. [Copyright &y& Elsevier]

The aim of this study was to determine oxidative stress status as well as blood lead (Pb) and zinc (Zn) levels and clinical markers in workers of a Zn-Pb mine. A comparative cross-sectional analysis was performed in 67 mine workers who have been in contact with Zn and Pb in comparison to a control group containing 67 healthy subjects with the same age and sex. Lipid peroxidation, superoxide dismutase, catalase, glutathione reductase, myleoperoxidase, DNA damage, total antioxidant capacity, Zn, and Pb levels were measured in blood of workers and controls. Clinical examination was accomplished to record any abnormal sign or symptoms. Comparing with controls, the workers showed higher blood levels of superoxide dismutase, myleoperoxidase, glutathione reductase, lipid peroxidation, Pb, and Zn. Workers showed lower DNA-damage as compared with controls. Workers showed clinical symptoms such as memory impairment, less of concentration, insomnia, headache, claudication, epigasteric, inappetence, agitation, tremor, decreasing of reflection of deep tendon, conduction deafness of ear, and fatigue. The workers had extra normal levels of Pb (0.9-3 μg/dL) and showed oxidative stress. Taken together, the results indicate that exposure to combination of Pb and Zn in mine elevates total antioxidant capacity of body in a reflex to overcome to oxidative stress. Especially, in the present case, it seems that toxic effect of Pb has been greater than positive effects of Zn, but the combination exposure has resulted in not such a critical toxicity situation. [ABSTRACT FROM AUTHOR]

The Viburnum Trend mining district in southeast Missouri, USA is one of the largest producers of lead–zinc ore in the world. Previous stream surveys found evidence of increased metal exposure and reduced population densities of crayfish immediately downstream of mining sites. We conducted an in-situ 28-d exposure to assess toxicity of mining-derived metals to the woodland crayfish (Orconectes hylas). Crayfish survival and biomass were significantly lower at mining sites than at reference and downstream sites. Metal concentrations in water, detritus, macroinvertebrates, fish, and crayfish were significantly higher at mining sites, and were negatively correlated with caged crayfish survival. These results support previous field and laboratory studies that showed mining-derived metals negatively affect O. hylas populations in streams draining the Viburnum Trend, and that in-situ toxicity testing was a valuable tool for assessing the impacts of mining on crayfish populations. [Copyright &y& Elsevier]

The potential effects of proposed lead-zinc mining in an ecologically sensitive area were assessed by studying a nearby mining district that has been exploited for about 30y under contemporary environmental regulations and with modern technology. Blood and liver samples representing fish of three species (largescale stoneroller, Campostoma oligolepis, n=91; longear sunfish, Lepomis megalotis, n=105; and northern hog sucker, Hypentelium nigricans, n=20) from 16 sites representing a range of conditions relative to mining activities were collected. Samples were analyzed for metals (also reported in a companion paper) and for biomarkers of metals exposure [erythrocyte δ-aminolevulinic acid dehydratase (ALA-D) activity; concentrations of zinc protoporphyrin (ZPP), iron, and hemoglobin (Hb) in blood; and hepatic metallothionein (MT) gene expression and lipid peroxidation]. Blood lead concentrations were significantly higher and ALA-D activity significantly lower in all species at sites nearest to active lead-zinc mines and in a stream contaminated by historical mining than at reference or downstream sites. ALA-D activity was also negatively correlated with blood lead concentrations in all three species but not with other metals. Iron and Hb concentrations were positively correlated in all three species, but were not correlated with any other metals in blood or liver in any species. MT gene expression was positively correlated with liver zinc concentrations, but neither MT nor lipid peroxidase differences among fish grouped according to lead concentrations were statistically significant. ZPP was not detected by hematofluorometry in most fish, but fish with detectable ZPP were from sites affected by mining. Collectively, these results confirm that metals are released to streams from active lead-zinc mining sites and are accumulated by fish. [Copyright &y& Elsevier]

The potential effects of proposed lead–zinc mining in an ecologically sensitive area were assessed by studying a nearby mining district that has been exploited for about 30yr under contemporary environmental regulations and with modern technology. Blood and liver samples representing fish of three species (largescale stoneroller, Campostoma oligolepis, n=91; longear sunfish, Lepomis megalotis, n=105; and northern hog sucker, Hypentelium nigricans, n=20) were collected from 16 sites representing a range of conditions relative to lead–zinc mining and ore beneficiation in southeastern Missouri. Samples were analyzed for lead, zinc, and cadmium, and for a suite of biomarkers (reported in a companion paper). A subset of the hog sucker (n=9) representing three sites were also analyzed for nickel and cobalt. Blood and liver lead concentrations were highly correlated (r=0. 84–0. 85, P<0. 01) in all three species and were significantly (ANOVA, P<0. 01) greater at sites <10km downstream of active lead–zinc mines and mills and in a historical lead–zinc mining area than at reference sites, including a site in the area proposed for new mining. Correlations between blood and liver cadmium concentrations were less evident than for lead but were nevertheless statistically significant (r=0. 26–0. 69, P <0. 01–0. 07). Although blood and liver cadmium concentrations were highest in all three species at sites near mines, within-site variability was greater and mining-related trends were less evident than for lead. Blood and liver zinc concentrations were significantly correlated only in stoneroller (r=0. 46, P<0. 01) and mining-related trends were not evident. Concentrations of cobalt and nickel in blood and liver were significantly higher (ANOVA, P<0. 01) at a site near an active mine than at a reference site and a site in the historical lead–zinc mining area. These findings confirm previous studies indicating that lead and other metals are released to streams from active lead–zinc mines and are available for uptake by aquatic organisms. [Copyright &y& Elsevier]

The article presents a study which examines the metal content of terrestrial plants in Enyigba-Abakaliki lead and zinc mine in Nigeria including zinc (Zn), lead (Pb) and cadmium (Cd). The study is investigated by graphite furnace AAS, nitric acid as base solution and soil sample analysis. Results show that concentrations in leaves has been affected by the bioavailability of heavy metal deposits in the soil.