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- An integrated investigation of the Rio tailings, Panasqueira mine, Centre PortugalPublication . Grangeia, Carlos; Ávila, Paula Freire; Matias, Manuel; Silva, E. Ferreira daThe risks associated with mine tailings have different nature and, thus, only a multiple approach can investigate and monitor comprehensively the characteristics and evolution of mine tailings impacts on the environment. Deposition at the Rio tailings (Panasqueira Mine) lasted about ninety years. Over one million cubic metres, of complex very fine to fine material, are deposited on a mountain side overlaying the Zezere river, increasing the risk of contamination of one of the most important hydrographic basins in central Portugal. Herein, a multidisciplinary study including geophysics, geochemistry and borehole information, organized in a GIS, is used to characterize the Rio tailings. The geophysical survey comprised ERT (Electrical Resistivity Tomography) and GPR (Ground Penetrating Radar) on the mud impoundment, as well as, on the slope of the tailings. The geochemical survey consisted on collecting water and tailings samples, iron coatings, arsenopyrite stockpile material and ferruginous crust. Samples collected in boreholes, drilled specifically for this project, were also analyzed. The GIS provided imaging of the geophysical, geochemical and particle size spatial distribution, so that comparisons between the different data sets are easily done. Resistivity and GPR allowed bedrock positioning. GPR was able to give layering results within the tailings. Finally, comparison and correlation between geophysical and geochemical results are carried out and evaluated on the GIS platform.
- Soil geochemical survey in Panasqueira mine surroundings (Central Portugal) : mining, metal(loid)s and related environmental impactPublication . Candeias, Carla; Salgueiro, Ana Rita; Silva, Eduardo Ferreira da; Ávila, Paula Freire; Melo, Rita
- Potentially toxic elements dynamics in the soil rhizospheric-plant system in the active volcano of Fogo (Cape Verde) and interactions with human healthPublication . Candeias, Carla; Ávila, Paula Freire; Sequeira, Cristina; Albuquerque, Manuel; Rocha, FernandoABSTRACT: Volcanic eruptions disturb directly and indirectly the ecosystems. Direct impact occurs on the soil-plant system with an input of new elements and indirect hazard occurs by consumption of these plants. Fogo island (Cape Verde Republic) has an active volcano and the last eruption occurred in 2014-15, expelling large amounts of materials that spread all over the island. Soils and edible plants were collected all over the island. Pollution indexes reveal contamination in all samples, mostly due to Hg and Ni and with moderate contribution of Co, Cr, Cu and Pb. Mercury is the PTE with higher contribution to the non-carcinogenic hazard quotient, both by soil ingestion and inhalation. Carcinogenic risk exceeds the target risk in all samples with the higher contribution of Ni. Transfer factor from soils to plants decreasing order is Mn > As > Zn > Cr > Cu > Cd > Pb > Ni > Co > Hg, being < 1 except for As and Mn (TF > 1 point to a significant accumulation of elements in edible plants). The hazard risk index and targeted hazard quotient shows that potential negative health outcomes can be induced by As, Cr, Cu, and Zn by consumption of edible plants.
- A review of exposure assessment methods for epidemiological studies of health effects related to industrially contaminated sitesPublication . Hoek, Gerard; Ranzi, Andrea; Alimehmeti, Ilir; Ardeleanu, Elena-Roxana; Arrebola, Juan P.; Ávila, Paula Freire; Candeias, Carla; Colles, Ann; Crisan, Gloria Cerasela; Dack, Sarah; Demeter, Zoltan; Fazzo, Lucia; Fierens, Tine; Fluckiger, Benjamin; Gaengler, Stephanie; Hanninen, Otto; Harzia, Hedi; Hough, Rupert; Iantovics, Barna Laszlo; Kalantzi, Olga-Ioanna; Karakitsios, Spyros P.; Makris, Konstantinos C.; Martin-Olmedo, Piedad; Nechita, Elena; Nicoli, Thomai; Orru, Hans; Pasetto, Roberto; Perez-Carrascosa, F.M.; Pestana, Diogo; Rocha, Fernando; Sarigiannis, Dimosthenis A.; Teixeira, João Paulo; Tsadilas, Christos; Tasic, Visa; Vaccari, Lorenzo; Iavarone, Ivano; de Hoogh, KeesABSTRACT: BACKGROUND: this paper is based upon work from COST Action ICSHNet. Health risks related to living close to industrially contaminated sites (ICSs) are a public concern. Toxicology-based risk assessment of single contaminants is the main approach to assess health risks, but epidemiological studies which investigate the relationships between exposure and health directly in the affected population have contributed important evidence. Limitations in exposure assessment have substantially contributed to uncertainty about associations found in epidemiological studies. OBJECTIVES: to examine exposure assessment methods that have been used in epidemiological studies on ICSs and to provide recommendations for improved exposure assessment in epidemiological studies by comparing exposure assessment methods in epidemiological studies and risk assessments. METHODS: after defining the multi-media framework of exposure related to ICSs, we discussed selected multi-media models applied in Europe. We provided an overview of exposure assessment in 54 epidemiological studies from a systematic review of hazardous waste sites; a systematic review of 41 epidemiological studies on incinerators and 52 additional studies on ICSs and health identified for this review. RESULTS: we identified 10 multi-media models used in Europe primarily for risk assessment. Recent models incorporated estimation of internal biomarker levels. Predictions of the models differ particularly for the routes 'indoor air inhalation' and 'vegetable consumption'. Virtually all of the 54 hazardous waste studies used proximity indicators of exposure, based on municipality or zip code of residence (28 studies) or distance to a contaminated site (25 studies). One study used human biomonitoring. In virtually all epidemiological studies, actual land use was ignored. In the 52 additional studies on contaminated sites, proximity indicators were applied in 39 studies, air pollution dispersion modelling in 6 studies, and human biomonitoring in 9 studies. Exposure assessment in epidemiological studies on incinerators included indicators (presence of source in municipality and distance to the incinerator) and air dispersion modelling. Environmental multi-media modelling methods were not applied in any of the three groups of studies. CONCLUSIONS: recommendations for refined exposure assessment in epidemiological studies included the use of more sophisticated exposure metrics instead of simple proximity indicators where feasible, as distance from a source results in misclassification of exposure as it ignores key determinants of environmental fate and transport, source characteristics, land use, and human consumption behaviour. More validation studies using personal exposure or human biomonitoring are needed to assess misclassification of exposure. Exposure assessment should take more advantage of the detailed multi-media exposure assessment procedures developed for risk assessment. The use of indicators can be substantially improved by linking definition of zones of exposure to existing knowledge of extent of dispersion. Studies should incorporate more often land use and individual behaviour.
- Spatial distribution approach to evaluate soil contamination in the surrounding area of Panasqueira minePublication . Salgueiro, Ana Rita; Candeias, Carla; Silva, Eduardo Ferreira da; Ávila, Paula Freire
- Assessment of the soil contamination by potentially toxic elements in Aljustrel mining area in order to implement soil reclamation strategiesPublication . Candeias, Carla; Silva, E. Ferreira da; Salgueiro, Ana Rita; Pereira, H. Garcia; Matos, João Xavier; Ávila, Paula Freire
- Mining activities in Panasqueira area : impact and threats in ecosystems and human health in rural communitiesPublication . Candeias, Carla; Silva, Eduardo Ferreira da; Ávila, Paula Freire; Coelho, Patrícia; Teixeira, João Paulo
- Metal(loids) bioaccessibility in road dust from the surrounding villages of an active minePublication . Candeias, Carla; Ávila, Paula Freire; Silva, Ferreira Da; Rocha, FernandoABSTRACT: Human activities, in general, cause a significant impact on the environment and human health. The present study aims to characterize the road dust of villages located near an active mine and to assess metal(loids) bioaccessible fractions. From the collected road dust samples (<250 µm fraction), the pseudo total, gastric (G) and gastrointestinal (GI) phase (UBM assay) concentrations, mineralogical composition, enrichment factor (EF), and risk for humans were determined. The obtained results revealed that arsenic represents the highest risk to humans, with mean pseudototal values higher than the maximum reference value range. The enrichment factor pointed to As as having significant to very high enrichment in all of the villages. In addition, Cd presented the maximum EF values in all of the villages, and was thus classified as having a very high enrichment. Particles enriched in As, Ca, Fe, Cu, Al, and Ti were identified by SEM-EDS in weathered agglomerates, and were linked to mine wastes and long-distance transport through both wind and/or traffic. The arsenic bioaccessibility fraction (%BAF) presented low values in the studied samples, possibly because of the low complex solubility of Fe with adsorbed As, limiting the release of arsenic and reducing its bioaccessibility. The concentrations of bioaccessible Cd for the G and GI phases were within the reference range, while for Cu, they were above and for Pb they were lower than the reference value range. The results show that the pseudototal fraction risk is overestimated when compared with BAF%; nevertheless, the total G and GI risks were above the carcinogenic target risk (1 × 10−6) in most of the samples. The carcinogenic risk of the bioaccessible contaminants showed that As represented the higher risk for developing cancer over a lifetime, with ingestion being the main risk route.
- Dust Characterization and Its Potential Impact during the 2014-2015 Fogo Volcano Eruption (Cape Verde)Publication . Candeias, Carla; Ávila, Paula Freire; Alves, Célia; Gama, Carla; Sequeira, Cristina; Silva, E. Ferreira da; Rocha, FernandoABSTRACT: Fogo (Fogo Island) is the youngest and most active volcano of Cape Verde. The last eruption occurred in 2014-2015. Aiming to assess the dust sources that impacted the air quality during the present study period, fresh lava samples were collected, while Saharan dust intrusions and transport were modeled. Rooftop dust was also collected on the island dwellings and a mineralogical and chemical characterization was undertaken. Air quality monitors were used to obtain concentrations of atmospheric particulate matter (PM) and gaseous pollutants. The mineralogical constitution was assessed by XRD and Electron Microprobe. The pseudototal chemical concentration was performed by XRF, ICP-MS and SEM; the latter includes particles morphology. During the study, WRF-CHIMERE results showed the intrusion of desert dust which affected the air quality. Lava was classified as tephritic to basanitic, with high potassium content. The Pollution Load Index for rooftop dust was > 1 in all samples, suggesting an enrichment. Higher values were found in dust size fraction < 63 mu m, with contamination factor pointing to high enrichment of As, Ni and Pb, and very high enrichment of Cd. The non-carcinogenic hazard estimated for children suggested that health problems may arise. The carcinogenic risk was above the target risk, mostly due to As > Pb > Co. Ingestion was the main exposure route. PM10 concentrations exceeded the 24-h mean of 50 mu g/m(3) recommended by WHO. Nevertheless, TVOCs displayed levels lower than guidelines. The highest levels of CO2 were recorded in more populated villages and farthest from the volcano.
- Heavy metal pollution in mine-soil-plant system in S. Francisco de Assis - Panasqueira mine (Portugal)Publication . Candeias, Carla; Melo, Rita; Ávila, Paula Freire; Silva, Eduardo Ferreira da; Salgueiro, Ana Rita; Teixeira, João PauloThe 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-1). 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.