759 research outputs found
Exposure to cobalt metal (without tungsten carbide) and some cobalt compounds: a literature review
Cobalt is a natural metallic element with extensive applications across multiple industries, and a
critical metal for lithium-ion battery production. Cobalt's only known biological function is its
role as a metal component of vitamin B12. Other cobalt compounds have been described as toxic
to the environment and the human body following excessive exposure. The International Agency
for Research on Cancer (IARC) has classified cobalt, including cobalt metal and soluble cobalt(II)
salts, as Group 2A, meaning it is probably carcinogenic to humans. This review aims to present a
comprehensive overview of historical and current sources of cobalt in diverse exposure settings,
along with its various intake routes. An extensive literature search was conducted between
September 2021 and January 2022, analysing over 300 publications. The primary goal of these
studies was to identify cobalt sources, intake routes, and exposure pathways. Workers may be
exposed to various cobalt compounds and metal powders primarily through inhalation, but exposure can also occur via skin contact or ingestion. For the general population, food typically
arises as the predominant source of cobalt exposure. Furthermore, exposure may occur through
ambient air, tobacco smoke, and medical implants
Reducing the carbon footprint through textile reuse: the case study of a textile valuation company
After food, housing, and transport, textiles are the fourth most pressured category in terms of raw material
and water use, and the fifth in terms of greenhouse gas emissions. In order to significantly reduce waste
and the use of natural resources in the textile and clothing industry, and to reduce the environmental impact
associated with the sector, thus contributing to sustainable development, there is a need to create business
models based on the principles of circular economy, in which clothes, fabrics, and fibers re-enter the
economy after their use. In environmental terms, we can say that reuse provides greater benefits than
recycling because it reduces the impact generated by the life cycle of textiles, particularly in reducing
greenhouse gas emissions (GHG). Currently, a few companies exist in the country to collect urban textile
"waste" with the purpose of textile valuation. Ultriplo (U3) is a nationwide company that aims essentially
at the valuation of collected textile waste by promoting reuse, contributing to sustainable development in
its environmental, social, and economic dimensions. The main objective of this study is to evaluate the
potential environmental benefits of reusing clothing at the end of product life, namely by reducing the
carbon footprint associated with the textile industry. For this study, the company provided a database for
the northern part of the country. The company's database is extensive and complex and can be described
simplistically as a table that compiles and integrates all the information regarding all the textile collection
routes. Furthermore, the database was limited to the first six months of the year 2021. In this study, only
variables such as Id, Start, End, Schedule, Mileage (Km), Total Pickups, Contentores, Filing, Weighing, Id
Contentor, MunicÃpio, Filing contentor (%), and Weighing contentor (kg) were used. These variables were
selected because they were required to evaluate the reduction in greenhouse gas emissions (GHG) resulting
from the textile reuse activity developed by U3. Each kilogram of clothing that is reused and not incinerated
avoids the emission of 3.169 kg of CO2e, according to data from the European Commission. This value was
used to acess the reduction in GHG emission reduction assessment methodology developed in this study.
This methodology has allowed estimating the amount of CO2e not emitted to the atmosphere at the
municipality scale. The results show that, for instance, for Santa Maria da Feira municipality, for the six
months under study, a total of 330,61 tonnes of CO2e were not emitted to the atmosphere due to the total
weight of clothes collected for reuse. The developed methodology has the potential to be replicated in other
regions of the country
Pandemia da COVID-19 na região Entre Douro e Minho: qual o impacto do confinamento na qualidade do ar?
A 11 de março de 2020, a Organização Mundial da Saúde declarou que a doença COVID-19 havia sido caracterizada como uma pandemia. Devido à rápida propagação do vÃrus, a 18 de março, o Presidente da República decreta o estado de emergência por 15 dias, o qual viria a ser prolongado até ao dia 2 de maio. Com o dever de recolhimento domiciliário, quase todas as atividades industriais e transportes em massa foram
proibidos. Após cerca de seis semanas de confinamento obrigatório, o desconfinamento viria a ser implementado em três fases.
A aglomeração Entre Douro e Minho contém seis estações de medição da qualidade do ar distribuÃdas pelas cidades de Braga, Guimarães, Santo Tirso, Paços de Ferreira e Paredes. Neste trabalho foram analisados com maior detalhe os poluentes medidos cuja monitorização é obrigatória, isto é, dióxido de azoto, matéria particulada de diâmetro inferior a 10 µm e ozono, com o monóxido de azoto e os óxidos de azoto
a serem utilizados essencialmente como auxiliares na interpretação dos resultados. A severa limitação do movimento de pessoas após o confinamento e subsequente desconfinamento resultaram numa redução significativa da concentração de dióxido de azoto atmosférico, principalmente devido ao tráfego de veÃculos. Apesar da redução significativa deste poluente nas fases confinamento e desconfinamento, o ozono apresentou um aumento significativo, provavelmente devido à menor concentração de monóxido
de azoto atmosférico. No entanto, são necessários dados adicionais para realizar uma
avaliação mais precisa.Projetos UIDB/04683/2020 e UIDP/04683/2020, financiados pela FCT - Fundação para a Ciência e a Tecnologia, I.P.
Developing a 3D Web-GIS Mapping Platform to support seismic vulnerability assessment of urban areas: an introduction
In 2020, natural disasters globally affected around 100 million people, causing
substantial economic and human losses. The population density in low-lying
coastal or riverside areas heightens the risk of significant impacts from natural
disasters. Due to its location, Portugal's tectonic environment induces low to
moderate seismic and co-seismic hazards with the potential for considerable
economic and human losses, especially in urban areas like Lisbon, underlying
the urgency for enhanced risk assessment and preparedness strategies. While
robust seismic risk models exist for Lisbon, the absence of a user-friendly tool
capable of automatically estimating real-time earthquake damages and safe
rescue pathways is a notable gap. This is where the proposed 3D web-GIS
platform will play an important role.
This platform aims to provide dynamic maps that illustrate the city's vulnerability
to these natural disasters. The incorporation of 3D model buildings will enhance
the visualization and communication of potential impacts and losses, thus
facilitating more effective preventive and response measures. The platform's
dynamic nature allows the integration of various models, including those for
assessing building collapse risks and identifying priority areas and safe rescue
routes. With dynamic, visual, and interactive representation of seismic risk data,
the platform will enhance seismic vulnerability comprehension and improve the
decision-making process for various stakeholders. For policymakers and urban
planners, this platform will offer a powerful tool for visualizing the potential
impacts of seismic events, aiding more effective urban planning and risk
mitigation strategies. It will also provide emergency response teams with critical
information for swift and safe response actions in the aftermath of an earthquake,
potentially saving lives and reducing economic losses, ultimately contributing to
safer, more resilient urban environments.
The PhD thesis, entitled "Developing a 3D Web-GIS Mapping Platform to Support
the Seismic Vulnerability Assessment of Urban Areas," which forms the basis of
this abstract, is in its early stage. The research is currently in a comprehensive
literature review, concentrating on seismic risk modelling, specifically in Lisbon City. This initial stage is crucial for identifying potential gaps and opportunities in
current methodologies, which will inform and guide the development of the webGIS platform.UIDB/04683/2020, DOI: 10.54499/UIDB/04683/2020; UIDP/04683/2020, DOI: 10.54499/UIDP/04683/202
Perspectives on environment and human health:an editorial
Human health and wellbeing are intimately linked to the state of the environment [...]</jats:p
Bioaccessibility by perspiration uptake of minerals from two different sulfurous peloids
Testing the risks of peloid usage in thermal centers, spas, or at home is essential for establishing safety guidelines regarding peloid formulations and releasing concerning substances. Additionally, evaluating the beneficial effects of specific elements on human health helps understand the therapeutic action and effectiveness of pelotherapy for dermatological or musculoskeletal disorders. A methodology was developed to study the biogeochemical behavior of elements in formulated peloids. With periodic stirring, two peloids were created with the same clay and two different sulfurous mineral-medicinal glasses of water for 90 days. Bentonite clay, rich in smectite and primary exchangeable cations Ca and Mg, with high heat capacity, was used. The mineral-medicinal waters were collected from recognized Portuguese thermal centers for their efficacy in treating rheumatic, respiratory, and dermatological pathologies. The peloids were used directly from the maturation tank without drying, and a reference sample of bentonite mixed with demineralized water was prepared. An artificial perspiration test simulated the peloids’ interaction with the skin. Thirty-one elements extracted from the two prepared peloids were analyzed using ICP-MS. The data were analyzed and compared to the original clay's mineralogical composition and the maturation tanks' supernatant composition. The solubility of potentially toxic elements and the bioaccessibility of metals through perspiration were low, with undetectable amounts extracted from the samples. This analytical method provided reliable information on dermal exposure and identifying elements that may enter the bloodstream, requiring the implementation of surveillance and control measures.Acknowledgement. FCT funded this research—Fundação para a Ciência e a Tecnologia and Exatronic, Lda, Grant Number SFRH/BDE/11062/2015 and also supported by GeoBioTec Research Centre (UIDB/04035/2020), funded by FCT, FEDER funds through the Operational Program Competitiveness Factors COMPETE
Mineralogical and petrographic characterization of Preguiça and Vila Ruiva mines
This study was performed on the Preguiça and Vila Ruiva mines and aimed at petrographic and mineralogical characterization of various geological media. The Preguiça and Vila Ruiva mines are two examples of the different types of Zn-Pb(-Ag-Sb-Au) deposits that occur in the Ossa Morena Zone, more specifically in the Moura-Ficalho region. Both deposits are in Serra da Preguiça, Beja district, and were explored for Fe-Zn-Pb in the early 20th century and between 1960 and 1966. In Preguiça and Vila Ruiva mines, the old exploration mainly targeted supergene enrichment areas, and information available on the primary mineralisation is scarce. The geology of the Preguiça-Vila Ruiva mining area consists of carbonate rocks that are affected by significant hydrothermal alteration (dolomitization and chertification), essentially composed of dolomite, calcite, and minor ankerite. Recent studies suggest that the Preguiça and Vila Ruiva deposits correspond to very rich secondary Zn-ores located in metadolostones of Lower Cambrian age due to strong in situ oxidation and supergene enrichment processes on previous sulphide mineralisation. Rock samples were collected from the gossans and the host rocks in the spring of 2022. In addition, local soil was sampled from the first 15cm of the soil profile. All rock and soil samples collected from Preguiça and Vila Ruiva were analysed by x-ray diffraction (XRD) and the host rock specimens were further studied using a petrographic microscope. The study of the Preguiça and Vila Ruiva thin sections suggests that the host rocks correspond to dolomitic meta-limestones manly with granoblastic texture, composed of dolomite, calcite, quartz, and opaque minerals. For the Preguiça mine, XRD shows that the dolomitic metalimestone has average dolomite contents of ~30%, while Vila Ruiva shows significantly higher contents (~80%) of this mineral. The Preguiça gossan is characterized by significant amounts of willemite (~52%), quartz (~40%), and iron oxides (goethite, hematite, and minor magnetite). Accessory minerals include chalcophanite and anglesite. At Vila Ruiva, the gossan is dominated by iron oxides, manly magnetite (~33%) and minor hematite (~17%) and goethite (~12%). In this mine, mineral phases such as willemite, chalcophanite and anglesite were not identified. The soils of Vila Ruiva present slightly higher amounts of quartz and lower contents of carbonate minerals than Preguiça soils. However, smithsonite (~12%) was only identified for Vila Ruiva, while cerussite (~3%) was identified only for Preguiça. Hematite is the most abundant iron oxide in the soils of both mines. Although the results suggest some differences in the gossans mineralogy of both mines, the small number of samples analysed largely justify further investigation
Natural attenuation processes in AMD context by mineralogical control: iron oxyhydroxides, oxyhydroxysulfates, and efflorescent sulfates
Acid mine drainage (AMD) is a common problem associated with the weathering of metal sulfide
wastes in abandoned mining areas, which can be rich in toxic metals and metalloids. Oxidative dissolution
of these minerals may negatively affect the soils and water reservoirs nearby. The formation of secondary
mineral phases such as iron oxyhydroxides, oxyhydroxysulfates, and efflorescent sulfates may be a natural
attenuation process in these areas because these minerals can scavenge potentially toxic elements. Typically
formed by the evaporation (efflorescent salts) or precipitation (ochreous iron-rich oxyhydroxides) these
minerals are highly soluble and reactive. Therefore, their characterization and inventory are particularly
important for predicting the cycles of retention/contamination or accumulation zones of potential toxic
elements (PTE) and acidity in mining contaminated systems.
The abandoned mines of Valdarcas and São Domingos were selected for the present study due to
their AMD signature and occurrence of some of these secondary minerals. Valdarcas (north of Portugal) is
a W-mine associated with a skarn deposit with sulfides that has already been rehabilitated. However, the
AMD problems remain in the watercourse that receives leachates from the waste dumps. São Domingos is
a Cu-mine composed of massive sulfide deposits that belong to the Iberian Pyrite Belt (south of Portugal).
This mining area, which is presently under remediation process, is highly contaminated and AMD is a longlasting problem. The samples collected in these mining areas were characterized by their morphology, size,
mineralogy, and chemical composition using different techniques: binocular microscopy, SEM-EDS, TEM,
BET, DRX, FTIR, and XPS.
In Valdarcas mine area, typical ochreous phases such as schwertmannite and goethite were
identified as the dominant secondary phases. These brownish-yellow ferric amorphous and poorly
crystalline minerals with high surface area (125 mg2
/m) can remove PTE via adsorption processes,
contributing to their retention in the mining environment. In contrast, at São Domingos, efflorescent sulfate
salts are more abundant. Melanterite and copiapite were the prevailing salts identified. With different
morphologies, these minerals are highly soluble and therefore play a relevant key in the
retention/mobilization cycles of hazardous contaminants, such as arsenic (As).
This integrative methodologic approach, based on the use of several techniques, allowed a
complete characterization of these minerals. In addition to composition, the surface properties that are
relevant for the adsorption ability, were also obtained. Therefore, the study revealed a diversity of behaviors
for the identified phases, suggesting various roles in increasing the resilience of the contaminated systems
Bioaccessibility by perspiration uptake of minerals from two diferent sulfurous peloids
The risks associated with the use of peloids in thermal centers, spas, or at home, must be tested to develop appropriate safety guidelines for peloids formulations and the release of substances of high concern. Additionally, the beneficial effects of some elements on human health should be assessed to aid in interpreting the therapeutic action and effectiveness of pelotherapy on dermatological or osteomuscular disorders. Therefore, a methodology was developed to better understand the biogeochemical behavior of the elements in formulated peloids. Two peloids were formulated with the same clay and two different sulfurous mineral-medicinal waters for 90 days, with light stirring every 15 days. Bentonite clay, with a high content of smectite and Ca and Mg as the main exchangeable cations, and high heat capacity, was used. The selected mineral-medicinal waters were collected from two Portuguese thermal centers with recognized therapeutic efficacy for rheumatic, respiratory and dermatological pathologies. The peloids were used without drying and withdrawn directly from the maturation tank, and a mixture of bentonite and demineralized water was prepared as a reference sample. A stabilized, ready-to-use, artificial perspiration test was used to simulate the peloids' interaction with skin. Thirty-one elements extracted from the two prepared peloids were analyzed using ICP-MS. The data were analyzed and related to the mineralogical composition of the original clay and supernatant composition of the maturation tanks. The content of some potentially toxic elements and metals' bioaccessibility by perspiration showed very low solubility and undetectable amounts extracted from the studied samples. This analytical method provided reliable information on dermal exposure and the identification of some elements that may enter the systemic circulation, requiring implementation of surveillance and control measures.Open access funding provided by FCT|FCCN (b-on). This research was funded by FCT—Fundação para
a Ciência e a Tecnologia and Exatronic, Lda, Grant Number SFRH/BDE/11062/2015 and also supported by GeoBioTec Research Centre (UIDB/04035/2020), funded by FCT, FEDER funds through the Operational Program Competitiveness Factors COMPETE
Geological setting of the chipindo mine: a preliminary analysis
As a contribution to the metallogenic model for the Chipindo mineral deposit, the preliminary characterization of the geology of the area is presented. The open-pit mine is located in HuÃla, Angola, and currently explores primary gold. It is included in the South Sheet D-33/J of Caconda from the Geological Map of Angola at 1:250 000 scale. - essentially, composed by leucocratic granites, with potassium feldspar phenocrysts of idiomorphic habit and poikilitic texture. The exploration targets mineralised quartz veins. For this work, and as part of a PhD thesis of Kumoleha A., a total of 49 rock and mineral samples were collected in the mining area for the lithological and mineralogical characterization of the deposit. 21 samples were collected in the mining area, including the mineralized structures, and host rocks. The field description encompasses i) Quartz associated with leucogranites; ii) Mineralized quartz veins; iii) Pegmatitic veins; iv) Strongly fractured quartz; v) Quartz veins with en-echelon structures; vi) Weakly mineralized quartz; vii) Highly altered and deformed volcanic tuffs; viii) Volcanic rocks, with copper sulphides (mainly bornite); ix) Altered dolerite rock. To characterise the regional geological setting, 20 rock samples were collected in the following geological units: a) Acid metavulcanites; b) Granites to biotitic-amphibolic, porphyroid granodiorites; c) Gabbros, diorites and quartz-diorites, variably foliated, metamorphosed and/or metasomatized; d) Coarse-grained porphyroid leucogranites. Eight samples of mine waste were collected from the floatation tanks for geochemical analysis and study of tailings, including the potential environmental impact. The sampling and sample description already carried out allows the preliminary characterization of this gold deposit. Future investigation will include mineralogical, geochemical, petrographic and metallographic studies that will certainly increase our understanding of the processes that formed this mineral deposit
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