Download or read book Distinguishing Between Natural and Anthropogenic Sources of Arsenic in Soils from the Giant Mine Northwest Territories and the North Brookfield Mine Nova Scotia written by and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Anthropogenic and geogenic sources of arsenic (As) have been identified in mining-impacted soils from the Giant mine (1948-1999), NT and the North Brookfield mine (1886-1906), NS. Both used roasting to extract gold from the arsenopyrite ore, decomposing it to As-bearing iron oxides (roaster oxides or RO) containing As, and releasing As3+-bearing arsenic trioxide (As2O3). Arsenic trioxide is considered highly soluble with the dissolved As3+ species being more mobile and toxic than other oxidation states. Soil profiles from the Giant mine show elevated As and antimony (Sb) at the surface (As=140-3300ppm) and decreasing concentrations with depth (As=22-600ppm). Surface soils contain anthropogenically-derived As2O3 identified using synchrotron methods (æXRD, æXANES) and environmental SEM. The persistence of As2O3 is attributed to Sb in As2O3 grains, dry climate and high organics in the soils. Anthropogenically-derived RO of maghemite (containing both As3+ and As5+) and natural arsenopyrite were observed. Sequential selective extractions (SSE) from surface soils show between 20% and 75% of As extracted in the crystalline iron-oxide phase is attributed to As2O3 and RO, while at depth As is bound by organics in the weaker leaches. North Brookfield mine soils show lower total As (2ppm to 45ppm) except near the roaster (4300ppm). No As2O3 was identified, probably due to the smaller scale and age of the mine, lower organic content and the lack of Sb. As-bearing phases include RO of hematite (As5+), As-rich rims on titanium-oxides, and As associated with clays and goethite. Adjacent to the roaster, SSE show As was also in the amorphous iron-oxide phase, also shown by As in arsenopyrite weathering rims. There are many differences between the North Brookfield and Giant mine soils including roasting techniques which produced different RO mineralogy, the scale of mining, climate, soil type, and the presence of As2O3. Currently, the Giant property is not publically accessible but m.
Download or read book The Metabolism of Arsenite written by Joanne M. Santini and published by CRC Press. This book was released on 2018-10-03 with total page 203 pages. Available in PDF, EPUB and Kindle. Book excerpt: Up to 200 million people in 70 countries are at risk from drinking water contaminated with arsenic, which is a major cause of chronic debilitating illnesses and fatal cancers. Until recently little was known about the mobility of arsenic, and how redox transformations determined its movement into or out of water supplies. Although human activities contribute to the release of arsenic from minerals, it is now clear that bacteria are responsible for most of the redox transformation of arsenic in the environment. Bacterial oxidation of arsenite (to the less mobile arsenate) has been known since 1918, but it was not until 2000 that a bacterium was shown to gain energy from this process. Since then a wide range of arsenite-oxidizing bacteria have been isolated, including aerobes and anaerobes; heterotrophs and autotrophs; thermophiles, mesophiles and psychrophiles. This book reviews recent advances in the study of such bacteria. After a section on background—geology and health issues—the main body of the book concerns the cellular machinery of arsenite oxidation. It concludes by examining possible applications. Topics treated are: The geology and cycling of arsenic Arsenic and disease Arsenite oxidation: physiology, enzymes, genes, and gene regulation. Community genomics and functioning, and the evolution of arsenite oxidation Microbial arsenite oxidation in bioremediation Biosensors for arsenic in drinking water and industrial effluents
Download or read book Arsenic written by Robert Bowell and published by Walter de Gruyter GmbH & Co KG. This book was released on 2014-11-21 with total page 668 pages. Available in PDF, EPUB and Kindle. Book excerpt: Environmental Mineralogy and Bio-Geochemistry of Arsenic provides a comprehensive understanding of arsenic geochemistry in the near-surface environment. Topics covered include the mineralogy, thermodynamics, geochemistry, analysis, microbiology, and bioavailability of arsenic, with emphasis on implications for arsenic toxicity, geochemistry in natural ground waters, and mine-associated impacts and possible mitigation options. This volume is useful for those seeking to understand arsenic geochemistry and biological interactions in the near-surface environment, Clay Minerals does not use an online manuscript tracking/submission system. as well those working for mining companies, the chemicals industry, NGO’s or government bodies concerned with reducing the impact of arsenic on the environment.
Download or read book Abstracts of Papers written by Geological Association of Canada. Meeting and published by . This book was released on 2008 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Arsenic Levels in the Yellowknife Area Distinguishing Between Natural and Anthropogenic Inputs written by Royal Military College of Canada. Environmental Sciences Group and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Determining Natural background Arsenic Soil Concentrations in Yellowknife NWT and Deriving Site specific Human Health based Remediation Objectives for Arsenic in the Yellowknife Area Final Report written by Canada. Environment Canada and published by . This book was released on 2002 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Impacts of Legacy Mining Operation on Inorganic Arsenic Bioaccumulation and Exposure in Yellowknife Northwest Territories Canada written by Claudia Tanamal and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Arsenic transfers and toxicology are important topics of research and a public health concern because arsenicosis affects millions of people worldwide every year. One of the most significant sources of arsenic in the environment is industrial wastes, such as by-products of mining operation. In Yellowknife, Northwest Territories, Canada, there were two large gold mines-Giant Mine and Con Mine, along with dozens of small-scale mines. The combined by-product of emission from these roasters might have contributed to high concentrations of arsenic found in the city. This thesis presents the results of two related studies to address the environmental health concern: (1) to investigate the arsenic transfers and arsenic species accumulation in freshwater food webs near large legacy mining operations in Yellowknife, and (2) to assess the long-term health risk of inorganic arsenic exposure from the consumption of fish in Yellowknife among the general residents and the Yellowknives Dene First Nation. We found that inorganic arsenic is biominified in food webs (i.e. inorganic arsenic concentrations diminish at higher trophic positions relative to lower trophic positions). Higher-trophic organisms have low inorganic arsenic concentrations in tissue due to biotransformation of inorganic arsenic to non-toxic organic arsenobetaine, and effective elimination of arsenic from their tissue. The trophic positions of freshwater organisms can be used to predict the range of arsenic concentrations and its species composition, accounting for more than 80% of variance. Dietary study results show that the Yellowknives Dene First Nation consumed significantly more fish in their diets (adults: 19 g/day, children: 9 g/day) compared to the general residents of Yellowknife (adults: 9 g/day, children: 5 g/day). Our probabilistic risk assessments showed no significant long-term non-carcinogenic and carcinogenic health risks of inorganic arsenic exposure from fish consumption for the majority of Yellowknife residents, but elevated cancer risks among the adult heavy fish consumers in Yellowknife. However, our data suggested that the residents of Yellowknife were not exposed to higher cancer risks from inorganic exposure compared to the general population in Canada. Therefore, due to fish health benefits and the values associated with its consumption, fish should continue to be a major source of sustenance in Yellowknife.
Download or read book Arsenic Natural and Anthropogenic written by Eleonora Deschamps and published by CRC Press. This book was released on 2011 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt: The discussion on arsenic in the environment is complex and must grasp the importance of very many, mostly unrelated works on individual aspects. This volume represents one of the first comprehensive and interdisciplinary examinations into arsenic's behaviour in air, water, soils, sediments, plants and the human body. Based on state-of-the-art investigations into the global arsenic cycle, the related human toxicology and available remediation technologies, arsenic is assessed holistically in all the environmental compartments. Using the results of primary research, the authors offer concrete suggestions for risk reduction and management of environmental pollution that allow the reader to successfully tackle similar problems and find sustainable solutions. The book consists of three essential parts: Review of the current knowledge of arsenic behaviour in the environment (global biogeochemical cycles), toxicology, remediation techniques, immobilization technologies and environmental legislation Case studies for mining-related arsenic problems Discussion of mitigation and remediation technologies and approaches such as environmental education, hygiene training, backed by real experience and successful implementation in the study area In a highly coherent manner, the book makes use of 120 tables and figures, a large number of literature citations, and very detailed subject index (that encompasses references) to provide rapid and up-to-date access to all relevant information. Cross-references provide a great manoeuvrability between the chapters. The book delivers very insightful and hands-on approaches for graduate students and professionals working on arsenic questions not only in environmental science, but also in the fields of environmental engineering, medicine and social science.
Download or read book Effects of soil composition and mineralogy on the bioaccessibility of arsenic from tailings and soil in gold mine districts of Nova Scotia written by L. Meunier and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Study of Arsenic Contamination from the Royal Oak Giant Mine Yellowknife Northwest Territories written by and published by . This book was released on 1998 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Determining Natural background Arsenic Soil Concentrations in Yellowknife NWT and Deriving Site specific Human Health based Remediation Objectives for Arsenic in the Yellowknife Area written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Survey and Comparison of Arsenic Concentrations in Water Soils and Vegetation Between the Venus Mine Property and the Mount Nansen Property Yukon written by Benoit Godin and published by . This book was released on 1985 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Arsenic Chemistry in Soils and Sediments written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Arsenic is a naturally occurring trace element that poses a threat to human and ecosystem health, particularly when incorporated into food or water supplies. The greatest risk imposed by arsenic to human health results from contamination of drinking water, for which the World Health Organization recommends a maximum limit of 10 [mu]g L−1. Continued ingestion of drinking water having hazardous levels of arsenic can lead to arsenicosis and cancers of the bladder, skin, lungs and kidneys. Unfortunately, arsenic tainted drinking waters are a global threat and presently having a devastating impact on human health within Asia. Nearly 100 million people, for example, are presently consuming drinking water having arsenic concentrations exceeding the World Health Organization's recommended limit (Ahmed et al., 2006). Arsenic contamination of the environment often results from human activities such as mining or pesticide application, but recently natural sources of arsenic have demonstrated a devastating impact on water quality. Arsenic becomes problematic from a health perspective principally when it partitions into the aqueous rather than the solid phase. Dissolved concentrations, and the resulting mobility, of arsenic within soils and sediments are the combined result of biogeochemical processes linked to hydrologic factors. Processes favoring the partitioning of As into the aqueous phase, potentially leading to hazardous concentrations, vary extensively but can broadly be grouped into four categories: (1) ion displacement, (2) desorption (or limited sorption) at pH values> 8.5, (3) reduction of arsenate to arsenite, and (4) mineral dissolution, particularly reductive dissolution of Fe and Mn (hydr)oxides. Although various processes may liberate arsenic from solids, a transition from aerobic to anaerobic conditions, and commensurate arsenic and iron/manganese reduction, appears to be a dominant, but not exclusive, means by which high concentrations of dissolved arsenic are generated. Within the subsequent sections of this chapter, we explore and describe the biological and chemical processes that control the partitioning of arsenic between the solid and aqueous phase.
Download or read book The Characterization Persistence and Bioaccessibility of Roaster derived Arsenic in Surface Soils at Giant Mine Yellowknife NT written by Mackenzie Jane Bromstad and published by . This book was released on 2011 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt: Approximately 20,000 tonnes of arsenic (As)-bearing emissions from roasting arsenopyrite ore were aerially released from 1949-1999 at Giant Mine, located outside Yellowknife, NT. As part of the process used to free refractory gold (Au) from arsenopyrite (FeAsS), roasting created As-bearing roaster off-gases that condensed into As2O3, one of the most toxic As compounds to humans. Roaster emissions also contained some As-bearing iron (Fe)- oxides. Arsenic emission controls were first implemented in 1951, and by the time the emission control process was completely refined in 1963, 86% of the total aerial As emissions at Giant had been released into the surrounding area. The continued presence of roaster-derived As2O3 in surface soils at Giant has been previously documented despite its theoretical instability in oxidizing surface environments. Wrye (2008) found As concentrations in roaster-affected soils occurring on rock outcrop (covering ~30% of the Giant property) greater than in many other surface soils; most outcrop soils were not considered when delineating areas of contaminated material for future removal in the Giant Mine Remediation Plan (currently undergoing environmental assessment). To investigate roaster-derived As persistence, outcrop soils and soil pore waters were analyzed. Comparing proportions of As, Sb, and Au concentrations in soil samples and historic As2O3-rich dust captured by emission controls show that most of the roaster-derived As in soils at Giant was likely deposited before 1964. Thin section examination has shown that while the vast majority of discrete As hosts in soils are As2O3, textural relationships and certain secondary As hosts in soils indicate that As2O3 is not static in surface soils and could be transforming over time, albeit very slowly. Bulk chemical relationships among As, antimony (Sb), and carbon support this. Topographic restriction by rock outcrops and dry, cold climate probably play a large role in elevated As concentrations and As2O3 persistence in outcrop soils. In light of possible future human exposure, As bioaccessibility from three adjacent samples was determined for synthetic human gastric (34%) and lung (18%) fluids.
Download or read book Assessment of Human Health Risks Posed by Arsenic Contamination in Yellowknife NWT Final Report written by Canada. Environment Canada and published by . This book was released on 2002 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Control of Arsenic Level in Gold Mine Waste Waters written by L. M. de Smecht and published by . This book was released on 1975 with total page 31 pages. Available in PDF, EPUB and Kindle. Book excerpt: Study of its chemistry of arsenic, the removal from waste waters using the Giant Yellowknife Mines as a case study, and the leaching of arsenic-bearing minerals.
Download or read book Arsenic in soil and groundwater environment biogeochemical interactions health effects and remediation written by and published by . This book was released on 2007 with total page 653 pages. Available in PDF, EPUB and Kindle. Book excerpt:
