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Since early 2000s, the increase in the exploitation of Mato Grosso deposits is a direct consequence to the increased price of gold (from 271 USD/troy ounce in 2001 up to the record high of 1669 USD/troy ounce in 2012, data from World Gold Council, ); the costs of mining gold have considerably risen as well, from 280 …
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The use of mercury in small-scale gold mining causes local and widespread regional and global pollution. • A systematic 25 × 25 km 2 net soil collection across the country was used to calculate spatial trends.. Background soil mercury concentrations in Ghana are low, but with large regional variation.
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Abstract Gold mining has profound ties to the history of Brazilian colonization and still takes place with many communities involved in artisanal and small-scale gold mining.
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In artisanal and small-scale gold mining (ASGM) the toxic metal mercury is used for gold extraction. The objective of this cross-sectional study was to assess …
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Keywords: Gravity concentration, leaching, small-scale mining, Sluice box. 1 Introduction Small scale gold mines are the mines that use relatively small and low-quality devices to extract ore containing gold from the earth's crust. This mine is currently operated by both licensed (trained
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This article reports on a stakeholder engagement process to develop the International Guidelines on Mercury Management in Small-Scale Gold Mining.
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1. Introduction. In recent decades, gold mining expanded from its historical core (South Africa, the United States, Canada, Australia, and Russia) into a wide range of new gold mining regions, many of them located in the global South (Verbrugge and Geenen, 2020).In addition to the expansion of large-scale industrial mining, many of …
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Artisanal and small-scale gold mining (ASGM) is the leading global source of anthropogenic mercury (Hg) release to the environment. Top-down mercury reduction efforts have had limited results, but ...
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Individuals involved in small–scale gold mining activities are exposed to increased levels of Hg vapor, since protective and preventive measures are not often used in mining areas. Protective measures such as fume hoods can be used to decrease mercury emissions and fumes. ... Urine Hg concentration is very stable and relatively …
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In other studies, Gyasi et al. [36] recorded relatively lower mean As concentration (0.16 mg/kg) in soil from Buruli Ulcer endemic communities in the Ashanti Region of Ghana, where activities of small-scale gold mining are high. The extremely high levels of As recorded in soils from Zone D is mainly from arsenopyrite gold-bearing …
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Artisanal and small-scale gold mining (ASGM) continues to expand rapidly due to the increasing global price of gold and the economic impacts of COVID-19. ... Dividing the mass of gold found in a sample. Gravity concentration. Due to the difference between the specific gravity of gold (SG = 19.3) and its common associate minerals, …
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A third of the Apamprama Forest Reserve, in Ghana's gold-rich Ashanti region, has disappeared in little more than 20 years. Satellite data show that forest loss …
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Small-scale mining crucial for mineral sovereignty. • Critical minerals key to national security. • Maps reveal inequalities in mining rights. • Sustainable technologies vital for mining. • Public policies needed for fair mining benefits.
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1. Introduction1.1. Mercury in mining. Although the use of mercury in large-scale mining operations has largely been eliminated, the practice has persisted in artisanal small-scale gold mining (ASGM), accounting for 37% of mercury emissions in 2010 and 24% of mercury demands in 2011 (UNEP, 2013).ASGM activities are largely …
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The gold standard for diagnosing VTE is imaging results, including computed tomography (CT) and ultrasound (US), which can be costly for patients in …
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Artisanal and Small-scale Gold Mining (ASGM) has been identified as the most important anthropogenic source of Hg at a global scale and an important route of human exposure to Hg. In this context, this study assessed total Hg (THg) in blood, urine and hair, and methylmercury (MeHg) in human hair samples from 238 participants with …
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In Ghana, a small-scale mining operation is defined as a mining operation over an area of land less than 21 hectares and under a small-scale mining license. However, most small-scale gold mining operations in Ghana have no license making their operations illegal. This illegal small-scale gold mining is popularly called "Galamsey" in Ghana.
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Artisanal and small-scale gold mining (ASGM) is a complex global development issue. ... Once the gold is liberated, gravity concentration techniques or others are applied to further concentrate the gold, free of other invaluable minerals. Mercury is used to capture gold particles during the ore processing stages in ASGM through a process called ...
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Key features include ores' concentration of gold, their depth underground, and the processing methods required by their form. ... It is a common processing method in small-scale gold mining around the world (Veiga et al., 2014) and has been ubiquitous throughout Pongkor for more than two decades. Cyanidation processors, as indicated by …
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This study investigates the distribution of total mercury (T-Hg) and methylmercury (MeHg) in the soil and water around the artisanal and small-scale gold mining (ASGM) area along the Cikaniki River, West Java, Indonesia. The concentration of T-Hg and MeHg in the forest soil ranged from 0.07 to 16.7 mg kg−1 and from <0.07 to …
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The workplace condition of small-scale mining is often very hazardous and difficult. 9 SSGM methods such as the use of gravity concentration in panning pose health risks among workers. 9 Furthermore, the nature of work of small-scale gold miners is physically demanding and dangerous due to heavy workloads, unstable underground …
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For artisanal and small-scale gold miners, mercury amalgamation provides a simple and inexpensive solution to recover gold. The process entails combining …
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To estimate the impact of mercury discharged from artisanal and small-scale gold mining (ASGM) activity, variations in the concentrations of elemental mercury (Hg0), mercury ion (Hg2+), particulate mercury (P-Hg), and total mercury in filtered river water (FT-Hg) were investigated from sampling locations extending from 10 km upstream to 30 km …
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Artisanal small-scale gold mining (ASGM) operations use mercury liberally in the gold extraction process and account for approximately one quarter of the anthropogenic mercury consumption worldwide. ... Gold has been analyzed in different matrices and at different concentration levels using fire analysis, flame atomic …
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Bench-scale gravity concentration was performed on the gold ore at varying clay contents (in the range of 5–30 wt.%) using Lab Knelson concentrator in the absence and presence of NaOH (2.5 kg/t ...
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Contamination Level in Geo-Accumulation Index of River Sediments at Artisanal and Small-Scale Gold Mining Area in Gorontalo Province, Indonesia. Basir, 1, 2, * Satomi Kimijima, 3 Masayuki ... Pb, As, and Zn had a concentration of 0–334 µg/g, 5.5–1930 µg/g, 0–18,900 µg/g, and 0–4923.2 µg/g, respectively, which exceeded limits ...
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Mercury (Hg) poses a public health burden in the Amazon and worldwide. Although usually attributed to Hg used in artisanal and small-scale gold mining (ASGM), the primary source of elevated Hg in Amazonian aquatic ecosystems is contested since there have not been tools to differentiate between Hg from ASGM and Hg from other …
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Mercury-based artisanal and small-scale gold mining (ASGM) causes more mercury pollution than any other human activity. 1 In this practice, mercury metal is used to extract gold from ore as a stable …
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The example of the application of the cash flow analysis was developed for the same mine as described in Seccatore et al. (2014a).It is a small underground gold operation located in Portolevo in southern Ecuador, a place with a long mining history and with a high incidence of AM (Cortazar, 2005, Cortazar and Lavanda, 2008).In Ecuador, …
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A preliminary assessment of toxic element pollution caused by artisanal and small-scale gold mining in the Bonsa river of Ghana as well as the influence of TOC and SO4 2− concentration on these traces in the sediment has been determined. With the exception of mercury (Hg), manganese (Mn), and arsenic (As), the concentration of …
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