The characterization of historical mine tailings provides important information for land-management decisions, in particular when considering potential reprocessing activities or the development of an environmental protection program. In addition, outcomes from such characterization may define the scope for a more detailed investigation. The present work describes the characterization of the waste material from the Cabeço do Pião tailings impoundment performed within the project ReMinE: Improve Resource Efficiency and Minimize Environmental Footprint.
View Article and Find Full Text PDFIn a circular economy concept, where more than 300 million tons of mining and quarrying wastes are produced annually, those are valuable resources, supplying metals that are extracted today by other processes, if innovative methods and processes for efficient extraction of these elements are applied. This work aims to assess microbiological and chemical spatial distribution within two tailing basins from a tungsten mine, using a MiSeq approach targeting the 16S rRNA gene, to relate microbial composition and function with chemical variability, thus, providing information to enhance the efficiency of the exploitation of these secondary sources. The tailings sediments core microbiome comprised members of family Anaerolineacea and genera Acinetobacter, Bacillus, Cellulomonas, Pseudomonas, Streptococcus and Rothia, despite marked differences in tailings physicochemical properties.
View Article and Find Full Text PDFConstructed wetland is a proven technology for water pollution removal, but process mechanisms and their respective contribution are not fully understood. The present review details the effect of plants on removal efficiency of constructed wetlands by focusing on literature that includes experiments with unplanted controls for organic carbon and nutrient (N and P) removal. The contribution of plant direct uptake is also assessed.
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
June 2017
Extensive reviews and meta-analyses are essential to summarize emerging developments in a specific field and offering information on the current trends in the scientific literature. Shale gas exploration and exploitation has been extensively debated in literature, but a comprehensive review of recent studies on the environmental impacts has yet to be carried out. Therefore, the goal of this article is to systematically examine scientific articles published between 2010 and 2015 and identify recent advances and existing data gaps.
View Article and Find Full Text PDFConstructed Wetlands (CWs) can be a valuable technology to treat high salinity wastewaters but it is not known their potential for removal of both nutrients and salt, and the type of plants to use. This study evaluated the effect of three plants on salt reduction and simultaneous nutrient removal in CWs microcosms with expanded clay and in hydroponic conditions. Initial values of the synthetic wastewater tested were EC=15dSm, SAR=151; NH-N=24mgL; PO-P=30mgL and NO-N=34mgL.
View Article and Find Full Text PDFSoil salinization affects 1-10 billion ha worldwide, threatening the agricultural production needed to feed the ever increasing world population. Phytoremediation may be a cost-effective option for the remediation of these soils. This review analyzes the viability of using phytoremediation for salt-affected soils and explores the remedial mechanisms involved.
View Article and Find Full Text PDFBackground And Objectives: The first case of Pulmonary Alveolar Proteinosis (PAP) was described by Rose in 1958, but it is still a rare disorder. PAP is characterized by deposition of lipoproteinaceous material secondary to abnormal processing of surfactant by macrophages. Patients may suffer from progressive dyspnea and cough that at times is accompanied by worsening hypoxia and its course can vary from progressive deterioration to spontaneous improvement.
View Article and Find Full Text PDFJ Environ Radioact
May 2013
The aim of this study was to assess by different approaches the occupational exposure during the remediation of a tailings dam in an abandoned uranium mining site, with an area of about 13.3 ha and an estimated volume of 1.39 million m³.
View Article and Find Full Text PDFResearch was performed to gain insight into the heterogeneous reaction of Cr(VI) reduction by zero-valent iron, which is frequently used in the treatment of contaminated groundwater using permeable reactive barriers. An electron probe microanalyzer was used to clarify in detail relevant aspects of the reaction with consequences for the conception of interpretative kinetic models. Spherical particles of iron with controlled grain sizes were used after being subjected to a previous washing with diluted acid in order to remove oxidation products.
View Article and Find Full Text PDFZero valent iron (ZVI) has been extensively used as a reactive medium for the reduction of Cr(VI) to Cr(III) in reactive permeable barriers. The kinetic rate depends strongly on the superficial oxidation of the iron particles used and the preliminary washing of ZVI increases the rate. The reaction has been primarily modelled using a pseudo-first-order kinetics which is inappropriate for a heterogeneous reaction.
View Article and Find Full Text PDFRespirometric tests on a soil contaminated by crude oil were performed. Continuous measurements of oxygen and carbon dioxide concentrations and temperature in the soil atmosphere resulted in a large volume of data. Time series and system identification theories were used to analyze data as a biological signal, allowing us to detect some particularities related to daily cycles of the studied variables as well as its time relationships through autocorrelation and cross-correlation functions.
View Article and Find Full Text PDFThe National Organ Donation Network is the structure that provides donation logistics for all transplant programmes currently functioning in Portugal (including cadaver donation, organs and tissues). In this article the authors present the Network, analyze the potential for heart donation, discuss the criteria for heart donor assessment and viability and suggest the adoption of recipient urgency grading schemes and the implementation of allocation criteria. In the coming years a realistic prediction for the maximum capacity of effective heart donation of the national network is 70-80 heart transplants per year, matching the figure of 7-8 heart transplants per million population and meeting 70-80% of the estimated needs for heart transplantation at national level.
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