Artisanal And Small-scale Gold Mining Research Articles

Assessment of Potentially Toxic Elements and Their Risks in Water and Sediments of Kitengure Stream, Buhweju Plateau, Uganda

Artisanal and small-scale gold mining (ASCGM) provides a livelihood for many communities worldwide, but it has profound environmental impacts, especially on the quality of nearby water resources. This study assessed the impacts of ASCGM on the physicochemical quality of water and sediments from Kitengure stream, Buhweju Plateau, Western Uganda. Surface water (n = 94) and superficial sediments (n = 36) were sampled between October 2021 and January 2022 from three different sections of Kitengure stream (upstream, midstream around the ASCGM area, and downstream). The samples were analyzed for various physicochemical parameters and selected potentially toxic elements (PTXEs), namely: zinc (Zn), cadmium (Cd), lead (Pb), copper (Cu), and arsenic (As). A health risk assessment was performed using the hazard index and incremental life cancer risk methods. Pearson’s bivariate correlation, geoaccumulation, and pollution indices were used to establish the sources and potential risks that PTXEs in sediments could pose to aquatic organisms. The results indicated that water in Kitengure stream draining the ASCGM site was highly colored (1230.00 ± 134.09 Pt-co units; range = 924.00–1576.00 Pt-co units) and turbid (194.75 ± 23.51 NTU; range = 148–257 NTU). Among the five analyzed PTXEs, only Cd (0.082 ± 0.200–0.092 ± 0.001 mg/L) and Cu (0.022 ± 0.004–0.058 ± 0.005 mg/L) were detected in water, and Cd was above the permissible limit of 0.003 mg/L for potable water. Upon calculating the water quality index (WQI), the water samples were categorized as very poor for upstream samples (WQI = 227) and unfit for use (WQI = 965 and 432) for midstream and downstream samples, respectively. In sediments, the mean concentration ranges of Zn, Cd, Pb, Cu, and As were 0.991 ± 0.038–1.161 ± 0.051, 0.121 ± 0.014–0.145 ± 0.025, 0.260 ± 0.027–0.770 ± 0.037, 0.107 ± 0.017–0.422 ± 0.056, and 0.022 ± 0.002–0.073 ± 0.003 mg/kg, respectively, and they were all below their average shale, toxicity reference, and consensus-based sediment quality guidelines. Geoaccumulation indices suggested that there was no enrichment of the elements in the sedimentary phase and the associated ecological risks were low. However, there were potential non-carcinogenic health risks that maybe experienced by children who drink water from Kitengure stream. No discernable health risks were likely due to dermal contact with water and sediments during dredging or panning activities. It is recommended that further studies should determine the total mercury content of water, sediments, and crops grown along the stream as well as the associated ecological and human health risks.

Examining Complexities of Artisanal and Small-Scale Gold Mining on Buru Island, Maluku Province, Indonesia

The Artisanal and Small-scale Gold Mining (ASGM) sector is presently one of the largest global sources of anthropogenic mercury emissions. The risk of mercury pollution from ASGM in Indonesia challenges other important industries including fisheries and tourism. Environmental degradation and risks to food safety and human health are major concerns that have been realised at local scales, including on Buru Island, Indonesia. Since the discovery of gold on Buru Island in 2011 the community has undergone dramatic changes. Some of these, such as rapid wealth accumulation, have been of benefit to people involved in the industry, however, they have been marred by negative social and economic consequences including rapid inflation, reduced rice production, and changes to the social fabric. We explore the Buru Island example through over 12 years of research interest and using empirical material through a socio-legal lens. Various legislative changes and government interventions have occurred since 2011 and there are complex interactions between industry players. Currently, the mining is low key with ore being transported to ‘back yard’ processing operations while a permitting system is anticipated. There is a legacy of land degradation and contamination as a result of the mining and ore processing. Alternatives to mercury are being considered but are challenged by uncertainty about product effectiveness, potential toxicity, and a lack of processing knowledge.

Mechanization of artisanal and small-scale gold mining in Guinea: Socio-technical trajectory of a rural mining site in Upper Guinea

Since the beginning of the 21st century, artisanal and small-scale gold mining (ASGM) in West Africa has undergone intensification and significant development due to the introduction of increasingly mechanized extraction and processing method. Mechanization generates significant transformations in the socio-technical dynamics of artisanal gold mining. In the specific context of ASGM in Upper Guinea, the article argues that small-scale innovations (ie. ‘low noise’ or ‘low technological level’ innovations) are leading to a profound socio-economic transformation of the rural environment over a long period of time. We begin by describing and analyzing the impact of the introduction of minor innovations (metal detectors, solonins and fan motors) on ASGM practices. We then examine the political, social and economic changes brought about by the adoption of these new mechanized practices, again at the rural level. Finally, we discuss the transition toward a new socio-technical regime, questioning the reshaping of local governance and its impact on new configurations of land ownership and use in rural areas.

Elevated total mercury (THg) levels in water sources under the influence of artisanal and small-scale gold mining (ASGM) in Tanzania.

This study investigated the presence and distribution of mercury in water bodies under the influence of artisanal and small-scale mining (ASGM) activities in Tanzania, which continue to predominantly rely on mercury for gold extraction. Various water bodies available for domestic and animal use in mining communities were sampled from surface water sources in ASGM settlements during the rainy and dry seasons. Water samples were analysed using cold vapour atomic fluorescence spectrophotometer (CVAFS). The results indicate that most of water sources had THg levels above the WHO guideline of 1.0µg/L (1000ng/L) for safe drinking water. The levels were significantly higher during the wet season ranging from 3.4 to 96.3µg/L, whereas the range was from 0.84 to 2.12µg/L during the dry period. The higher THg values during the wet season are likely a result of increased lateral transport (e.g. via enhanced runoff) and physical properties of the waterways. Transportation and resuspension of matrix-bound mercury from surface soils and inflow of contaminated water from unprotected tailings were also observed to be potential means of lateral mercury transport. The lowest concentrations (0.846µg/L) were observed in water samples from the Mabubi River, upstream of a mining village. Downstream of the mining village in the same river, higher concentrations were observed in the Nungwe Bay region of Lake Victoria. In other surveyed mining settlements where there were no nearby rivers, pool water indicated high concentrations of THg, including levels above thresholds for safe human use. Immediate stringent measures are needed in order to ensure human and animal safety at ASGM mining settlements. Future investigation is suggested to focus on the distribution of mercury in different media, assessing the prevalence of different mercury species, and investigating the influence of weather and hydrological conditions on the impacts of mercury to organisms as part of the strategies to mitigate mercury pollution.

Technology, capital, and sustainability: Frontiers in just transitions for African mining

Transitions towards sustainability are crucial in the natural resource sector in Africa, particularly in artisanal and small-scale gold mining (ASGM). This sector is notably characterized by the extensive use of mercury for gold extraction, which poses significant risks to both human health and ecosystems. This study focuses on Tanzania, where international incentives to reduce mercury have led the state to promote alternative methods and scale up production primarily through cyanide leaching—a more mechanized gold extraction technique.This article examines the implementation of these strategies, identifies the barriers hindering this transition, and explores the resulting inequalities. We employ a mixed methods approach, combining surveys, semi-structured interviews, and participant observation. We adopt the Sustainability and Just Transitions frameworks for the Global South, arguing that applying an in-depth relational approach to the interactions between actors and technologies can illuminate the persistence of environmentally unsustainable practices within the local context. In conclusion, we advocate for international strategies aimed at the Global South to consider the how promoting the eradication of environmentally unsustainable practices can affect livelihood creation mechanisms.

Community engagement in mobile and hard-to-reach populations: a community-based intervention for malaria elimination in a tri-national region of the Guiana Shield.

Several countries of the Guiana Shield are aiming at the control and elimination of malaria in areas where Artisanal and Small-scale Gold Mining (ASGM) activities predominate, raising questions about how to strengthen community engagement to improve the effectiveness of health programs. The Curema project focuses its intervention on the mobile and hard-to-reach ASGM population, complementing the efforts of national programs in the Guiana Shield. The Curema intervention combines targeted drug administration for suspected Plasmodium vivax asymptomatic carriers, the Malakit distribution, and health education activities. The primary goals of this manuscript are to outline a pathway to foster community participation in the Curema project aimed at eliminating malaria. Thus, it presents a vision of the challenges that the AGSM community poses in terms of community participation for an asymptomatic problem; and highlights the community-based model and the Information, Education and Communication (IEC) components as foundations for participation. In addition, it also presents culturally sensitive IEC strategies designed through iterative and collaborative consultative processes and other bottom-up outreach activities. The community engagement approach facilitates adaptability and responsiveness in a complex, evolving context increasing the effectiveness of interventions.

Evaluating ecological risks and metal bioavailability in post-dredging sediments of a wetland affected by artisanal gold mining

The evaluation of metal contamination, ecological risk, bioavailability, and the environmental dredging depth in sediments of two Colombian riverine systems impacted by artisanal gold mining and agricultural activities, was conducted following dredging processes. Results indicated significant contamination by Cd and Pb before dredging, based on the contamination factor (CF) and the geoaccumulation index (Igeo). Additionally, Cu and Hg were found to cause adverse biological effects according to sediment quality guidelines. Post-dredging, surface sediments exhibited a moderate ecological risk index (RI, 150–300), primarily due to increased contamination by Hg, Pb, and Cd. To mitigate this ecological risk (RI < 150), the environmental dredging depth needed to exceed 20 cm for all metals. On average, the bioavailable fraction increased 2.3 times within two months after dredging. However, the low environmental risk (%F1 = 1–10) calculated using risk assessment codes (RAC) indicates a potential risk due to metals entering the water column and bioaccumulating in organisms. These findings provide insights into the dynamics of metals and the impact of dredging activities on sediments in the Colombian Caribbean coast affected by various anthropogenic activities. The research underscores the importance of integrating sustainable practices in mining and agriculture to protect the ecological integrity of these riverine systems.

Mercury in river samples with artisanal and small-scale gold mining influence: The case of the upper Madeira River Basin (Brazil/Bolivia)

The issue of mercury (Hg) is becoming a growing concern in the Amazon basin. The Madeira River is known for intense artisanal and small-scale gold mining (ASGM), and Hg poses a significant issue for public health and ecosystems. In this study, we analyzed Hg riverine concentrations in water samples, suspended particulate matter (SPM) and sediments in the Upper Madeira River Basin. We also examined mineralogical and elemental compositions of the solid phase to enhance our understanding of Hg behavior in the environment. Dissolved Hg was not detected in water, and Hg concentrations in solids remained in the same order of magnitude across different rivers, despite variations in gold mining intensities along their courses. Generally, Hg concentrations were higher in compartments with a greater proportion of fine sediments (clay and silt), with average concentrations of 91.4 ± 13.0, 41.6 ± 11.0, and 22.2 ± 1.6 ng g−1 for SPM (n = 14), riverbank (n = 12), and riverbed (n = 4) sediments, respectively. Multivariate analysis shows Hg chemical associations related to clay minerals and organic matter (OM) for the riverbank and SPM compartments. However, in SPM, OM had a greater influence on Hg distribution. Conversely, one riverbed sample highlights with a high Hg concentration (547.78 ng g−1), large content of heavy minerals, and a distinct geochemical signature. This sample was collected in a river section upstream of Beni River's rapids where the river's hydrodynamics can induce the high concentration of heavy minerals in this riverbed sediment. This unexpectedly high Hg concentration encountered in sediment rich in heavy minerals is likely related to contamination by Hg-rich mine tailing discarded into the river. Overall, this study discusses the issue of Hg mobility in rivers suggesting its dispersion, i) associated with fine fraction rich in clay and OM, and ii) associated with heavy minerals.

Optimization of direct smelting for mercury-free gold recovery in artisanal and small-scale gold mining

Artisanal and small-scale gold mining (ASGM) faces challenges in accessing capital, technology, and responsible practices, hindering sustainable operations and contributing to environmental and health impacts from mercury use. This study evaluated optimizing direct smelting of gold concentrates as an alternative to mercury amalgamation for efficient and responsible production. 50 kg of ore from Nholi mine was concentrated using a Knelson concentrator and analyzed (XRF, fire assay with AAS, XRD). Response surface methodology with a face-centered composite design investigated smelting temperature (1100–1400 °C), duration (30–90 min), and concentrates-to-flux ratio (1:1–3:1) effects. The impact of sulfide concentration (pyrite varied 6.7–48%) on gold recovery was explored. Low-sulfide concentrates associated with pyrite and sphalerite yielded best recovery (&gt;80%) at 1250 °C for 90 min with 2:1 concentrates-to-flux ratio. Direct smelting with ≤6.7% sulfide enabled over 87% gold recovery, facilitating responsible ASGM production.

Assessing soil contamination by potentially toxic elements in artisanal and small-scale gold mining sites of the Adamawa Region, Cameroon

Gold mining is acknowledged as a principal source of environmental contamination, primarily due to the release of potentially toxic elements (PTEs) through tailings dispersion into adjacent soils. Such contamination leads to land degradation, pollution, biodiversity loss and soil contamination, and subsequently impacts the food chain, human health and soil ecosystems. This study evaluates the extent of PTE contamination in soils at artisanal and small-scale gold mining (ASGM) sites within the Meiganga area of the Adamawa-Yade Domain, Cameroon. ASGM extraction processes from quartz veins in this area involve the removal of topsoil to access the ore. Comparative analysis of soil samples from three profiles within the mining zone were conducted to determine contamination levels using pollution indices: enrichment factor, geoaccumulation index, contamination factor and pollution load index. Results indicate higher concentrations of PTEs in soils from the mining area compared to the control profile, with notable contamination in the bottom slope profiles and B horizons, reflecting considerable metal accumulation. The contamination levels of PTEs substantially exceed background levels in the upper continental crust. The study attributes the elevated concentrations of PTEs not only to local mineralization but also to anthropic activities, particularly ASGM, which contributes to their enrichment, distribution and mobility. This pronounced contamination necessitates immediate intervention, advocating for pollution-control measures to address potential ecosystem and human health risks. It highlights the environmental toll of ASGM and underscores the imperative for sustainable mining practices and effective soil remediation techniques, including phytoremediation and soil replacement, to alleviate the adverse effects.

Health and environmental risk assessment of mercury in outdoor and indoor dust in artisanal and small-scale gold mining area in Amansie-west district in the Ashanti Region of Ghana.

Mercury (Hg) pollution around artisanal and small-scale gold mining (ASGM) areas has been of much concern. Many studies have reported elevated Hg concentrations in environmental media, but studies on dust relating to inhalation exposure of Hg around ASGM area are limited. In this study, we investigated Hg in indoor and outdoor dust to reveal environmental and human health risk around ASGM in Amansie West district, Ghana. Indoor and outdoor dust samples were collected from Manso Abore and Manso Nkwanta in Ashanti Region. Concentration of Hg in the samples were analyzed using a direct Hg analyzer. The mean and median value of Hg concentration in the indoor dust (n = 31) were 2.2 ± 3.6mg/kg and 0.72mg/kg respectively while that of the outdoor dust (n = 60) were 0.19 ± 0.48mg/kg and 0.042mg/kg, respectively. The mean and median Hg concentration in indoor dust were about 11 and 17 times higher respectively than that in the outdoor dust. The Hg concentration in the indoor dust was statistically significantly higher than that of the non-miner in Manso Abore (p < 0.05) but was not significant in Manso Nkwanta, probably due to higher mining activity. The geo-accumulation index of the outdoor dust ranged from unpolluted to extremely polluted while that of the indoor dust ranged from moderately polluted to extremely polluted. Health risk assessments suggested that there was no potential non-carcinogenic health effect for Hg exposure relating to the dust to residents living in rooms of miners and non-miners.

An Investigation of the Carbon Emissions and Climate Change Awareness from the Artisanal and Small-scale Gold Mining (ASGM) sector in Guyana: The Case of Mahdia

Mineral extractive industries are becoming increasingly relevant in climate change science and policy. Guyana’s economic policy, the Low Carbon Development Strategy, seeks to align sectors of the economy along a low carbon emission trajectory. Although the artisanal and small-scale gold mining (ASGM) sector is economically important, it is a known emissions-intensive sector that contributes to deforestation and direct operational emissions. This study sought to increase understanding of direct operational emissions by investigating carbon emissions associated with fuel combustion in ASGM. Further, the study investigated miners’ awareness of carbon emissions and willingness to reduce emissions; thus providing context for policymakers to advance measures aimed at reducing carbon emissions in the ASGM sector. The research methods used were qualitative document analysis, questionnaire-survey, and interviews. It was found that the average carbon dioxide emission per volume of earth moved from a sample of ASGM operations in Mahdia per quarter was 4.69 x 10-6 MtCO2e/m3. Miners were generally unaware of their carbon footprint and its link to mining, climate change, and the Low Carbon Development Strategy. This knowledge gap was accompanied by negative attitudes. 79% of miners indicated there was no need to reduce their carbon footprint, and 85% of miners were unwilling to change their usual practices. Recommendations to advance and integrate the sector within the Low Carbon Development Strategy framework were explored within the themes of: regulation and management; fiscal measures; technology; and education and awareness.

Repeated mining accounts for the majority of artisanal and small-scale gold mining activity in Southeastern Peru

Artisanal and small-scale gold mining (ASGM) is considered a leading cause of environmental degradation in the Amazon. Previous studies have only used deforestation to quantify total ASGM activity and have not considered that mining may occur multiple times in the same area. However, miners often revisit previously mined sites to extract additional gold, though the frequency and extent of this occurrence remains unquantified. This study is the first to quantify repeat ASGM in Madre de Dios, Peru, and to identify which factors best predict revisitation. We found that nearly two-thirds of total ASGM activity in this region is repeat mining. When repeat mining activity is accounted for, we found that 249 488 ha were mined from 1984–2021, which is 265% more than activity estimates based on deforestation due to initial ASGM alone. Random Forest modeling showed that the designation, region, size, and type of a mine were the most important predictors of repeat mining. We suggest that repeat mining must be considered for a more comprehensive view of ASGM activity and its environmental impacts.

“Hg distribution and accumulation in soil and vegetation in areas impacted by artisanal gold mining in the Southern Amazonian region of Madre de Dios, Peru.”

Artisanal and small-scale gold mining (ASGM) is the primary global source of anthropogenic mercury (Hg) emissions. It has impacted the Amazon rainforest in the Peruvian region of Madre de Dios. However, few studies have investigated Hg's distribution in terrestrial ecosystems in this region. We studied Hg's distribution and its predictors in soil and native plant species from artisanal mining sites. Total Hg concentrations were determined in soil samples collected at different depths (0–5 cm and 5–30 cm) and plant samples (roots, shoots, leaves) from 19 native plant species collected in different land cover categories: naked soil (L1), gravel piles (L2), natural regeneration (L3), reforestation (L4), and primary forest (L5) in the mining sites. Hg levels in air were also studied using passive air samplers. The highest Hg concentrations in soil (average 0.276 and 0.210 mg kg−1 dw.) were found in the intact primary forest (L5) at 0–5 cm depth and in the plant rooting zones at 5–30 cm depth, respectively.Moreover, the highest Hg levels in plants (average 0.64 mg kg−1 dw) were found in foliage of intact primary forest (L5). The results suggest that the forest in these sites receives Hg from the atmosphere through leaf deposition and that Hg accumulates in the soil surrounding the roots. The Hg levels found in the plant leaves of the primary forest are the highest ever recorded in this region, exceeding values found in forests impacted by Hg pollution worldwide and raising concerns about the extent of the ASGM impact in this ecosystem. Correlations between Hg concentrations in soil, bioaccumulation in plant roots, and soil physical-chemical characteristics were determined. Linear regression models showed that the soil organic matter content (SOM), pH, and electrical conductivity (EC) predict the Hg distribution and accumulation in soil and bioaccumulation in root plants.

Soil and Urine Mercury Levels in Secocha: A Case Study of Artisanal and Small-Scale Gold Mining in Peru

In recent decades, artisanal and small-scale gold mining (ASGM) has spurred population and economic growth in the small rural communities in which it is located, along with causing contamination of the soil, air, and water with grave effects on human health due to the uncontrolled use of mercury for gold processing activities. This study analyzes the levels of mercury in Secocha, an ASGM community in Arequipa, Peru. A total of 44 soil samples were taken from two ASGM commercial-extractive zones (n = 18) and non-processing urban zones (n = 26). Soil mercury analysis with atomic absorption spectrometry revealed average mercury levels of 86.11 mg/kg in commercial-extractive zone I, where ore processing has occurred for about 17 years, and mercury levels of 43.81 mg/kg in commercial-extractive zone II, where processing has occurred for about 7 years. In the urban zone, the average mercury level was 9.53 mg/kg. The average mercury concentrations for each zone exceed the relevant environmental quality standards established by the Peruvian Ministry of the Environment. In addition, urine samples were obtained from 15 miners and 15 people from the general urban population (non-miners). The average mercury level in the urine of miners was 7.04 µg/L, and in the urine of non-miners it was 0.49 µg/L. In both cases, the mercury urine level did not exceed the limits established by WHO and the Peruvian Ministry of Health, though miners’ elevated levels do raise concerns.

Perspective on Artisinal and Small-scale gold Mining: Ecological and Socio-economic Inovation

Global aspirations for stringent mercury regulations have not been translated effectively in Russia, largely due to the emergence of new domestic cinnabar mining ventures. These initiatives have increased locally sourced mercury, reducing its cost and undermining efforts to curtail its use. This study employs Stochastic Multicriteria Acceptability Analysis (SMAA) within an environmental finance framework to rigorously assess the challenges associated with mitigating mercury use in artisanal and small-scale gold mining (ASGM) in Russia. The sampling period for the research spans from June to September 2018 in the Krasnoyarsk Krai area, comprising Yeruda and Chebyzhek villages in the Kurakhinsky district and Abalatskoye village in the Minusinsky district. The paper investigated these complexities using SMAA to identify the multifaceted challenges in implementing the Minamata Agreement, a global treaty committed to regulating and curtailing mercury use. The findings revealed that mercury management is associated with various socioeconomic factors, labor relations, and power structures that have collectively hindered mercury-free practices in gold mining. Therefore, this study highlighted the critical need for a holistic, sustainable economic framework by incorporating new insights into the societal metabolic functions of dynamic mineral finance. Utilizing SMAA within the specific context of native employment conditions, the authors challenged the prevailing norms and offered robust, data-driven strategies aimed at reducing or eliminating mercury usage in ASGM.

Diet choices determine mercury exposure risks for people living in gold mining regions of Peru

Artisanal and small-scale gold mining (ASGM) is the largest global anthropogenic mercury (Hg) source and is widespread in the Peruvian Amazon. Consuming Hg-laden foods exposes people to this potent neurotoxin. While numerous studies have examined fish Hg content near ASGM, Hg accumulation in other commonly consumed animal-and plant-based foods from terrestrial environments is often overlooked. In this study, we aim to address understudied dietary Hg exposures.To understand Hg exposure from food staples in the Peruvian Amazon, we measured total and methyl Hg in local crops, fish, chicken meat, chicken feathers, and eggs from ASGM-impacted and upstream (reference) communities. Diet surveys were used to estimate probable weekly Hg intake from each food. Fish and chicken stable carbon and nitrogen isotope signatures were analyzed to evaluate trophic magnification.Though few crops exceeded food safety recommendations, rice methyl Hg proportions were high (84%). Trophic level was an expected key predictor of fish Hg content. 81% (17 of 21) of local carnivorous fish exceeded WHO and EPA recommendations. Compared to upstream communities, mining-impacted communities demonstrated elevated total Hg in crops (1.55 (interquartile ranges (IQR): 0.60–3.03) μg kg−1 upstream versus 3.38 (IQR: 1.62–11.58) in mining areas), chicken meats (2.69 (IQR: BDL–9.96) μg kg−1 versus 19.68 (IQR: 6.33–48.1)), and feathers (91.20 (IQR: 39.19–216.13) μg kg−1 versus 329.99 (IQR: 173.22–464.99)). Chicken meats from mining areas exhibited over double the methyl Hg concentrations of those upstream. Methyl Hg fractions in chicken muscle tissue averaged 93%. Egg whites and livers exceeded Hg recommendations most frequently. Proximity to mining, but not trophic position, was a predictor of chicken Hg content.Our results demonstrate that terrestrial and aquatic foods can accumulate Hg from mining activity, introducing additional human Hg exposure routes. However, locally sourced carnivorous fish was the largest contributor to an estimated three-fold exceedance of the provisional tolerable weekly Hg intake.

Assessment of Mercury Contamination in Water and Soil from Informal Artisanal Gold Mining: Implications for Environmental and Human Health in Darmali Area, Sudan

Mercury contamination stemming from artisanal and small-scale gold mining (ASGM) operations poses significant environmental and health concerns. This study focuses on the Darmali area in River Nile State, Sudan, where the reprocessing of amalgamation tailings has led to mercury contamination. This study assessed the mercury content in soil and tailings samples, as well as in tap and groundwater, to evaluate the human health risks from ASGM activities and assess contamination levels within the study area. Soil and water samples were collected from various locations, including agricultural, residential, and tailings sites, as well as groundwater and tap water from the Nile. Mercury analysis was conducted using MA-3000 (NIC), and geo-accumulation index analysis revealed extreme pollution levels in areas with tailings and moderate pollution levels in agricultural and residential areas. Hazard quotients were applied to assess health risks, with inhalation of mercury vapor identified as the primary exposure route. The results indicated that tailings pose significant health risks, particularly for children, while water samples and soil from agricultural and residential areas did not pose significant risks. These findings underscore the urgent need for authorities and local communities to address mercury contamination by removing and treating tailings from affected areas to mitigate health risks.

Artisanal and small-scale gold mining and biodiversity: a global literature review.

Artisanal and small-scale gold mining (ASGM) is crucial to the livelihoods of close to 20 million people in over 80 countries, including 4-5 million women, mainly in rural areas with limited alternative economic prospects, particularly in developing countries. ASGM is largely informal, which can add to the challenge of addressing negative social and environmental effects including impacts on biodiversity. However, with proper guidance, ASGM can operate in a responsible manner, using cleaner production methods that minimize impacts on human health and the environment. This study presents and analyzes the interactions between ASGM and biodiversity based on new findings from 27 ASGM National Action Plans (NAPs) developed within the framework of Article 7 and Annex C of the Minamata Convention on Mercury, as well as a global literature review of more than 100 publications. In terms of key findings according to the literature reviewed, alongside other human occupation such as agriculture and industrial activities, ASGM also has an impact on the environment and biodiversity. The interrelationship between ASGM and biodiversity, including protected areas, is pervasive at every stage of ASGM operations, from extraction to mine closure, and generates significant impacts on the surrounding ecosystems. These impacts include, in descending order of most reported impacts: deforestation, soil degradation, chemical contamination of aquatic and terrestrial systems, and changes to the turbidity of watercourses. Tropical regions and key species such as amphibians and freshwater fish are among the most affected. Singly or combined, these environmental stressors lead to loss or deterioration of habitat and, by extension, indigenous biodiversity and ecosystem services. In addition, legal, institutional, and regulatory frameworks and related measures, inadequate or non-existent in some cases, may not necessarily support sustainable practices, often resulting in exploited sites abandoned without remediation, reclamation, rehabilitation, or restoration measures. To mitigate such impacts a key recommendation arising from the literature review is to strengthen the integration of the interrelationship between ASGM and biodiversity in the implementation of existing relevant national strategies, including those developed under the NAPs. The global literature review also highlights the importance of a multi-stakeholder, systemic approach combining the use of geospatial analysis, scientific and local knowledge, as well as the adaptation of the relevant frameworks, capacity building, and awareness raising. This approach can inform decision making with a view to developing sustainable initiatives that prevent and reduce the impacts of artisanal and small-scale gold mining on ecosystems, and that preserve biodiversity.

Risks to Human Health from Mercury in Gold Mining in the Coastal Region of Ecuador.

Artisanal and small-scale gold mining (ASGM) plays a crucial role in global gold production. However, the adoption of poor mining practices or the use of mercury (Hg) in gold recovery processes has generated serious environmental contamination events. The focus of this study is assessing the concentration of Hg in surface waters within the coastal region of Ecuador. The results are used to conduct a human health risk assessment applying deterministic and probabilistic methods, specifically targeting groups vulnerable to exposure in affected mining environments. Between April and June 2022, 54 water samples were collected from rivers and streams adjacent to mining areas to determine Hg levels. In the health risk assessment, exposure routes through water ingestion and dermal contact were considered for both adults and children, following the model structures outlined by the U.S. Environmental Protection Agency. The results indicate elevated Hg concentrations in two of the five provinces studied, El Oro and Esmeraldas, where at least 88% and 75% of the samples, respectively, exceeded the maximum permissible limit (MPL) set by Ecuadorian regulations for the preservation of aquatic life. Furthermore, in El Oro province, 28% of the samples exceeded the MPL established for drinking water quality. The high concentrations of Hg could be related to illegal mining activity that uses Hg for gold recovery. Regarding the human health risk assessment, risk values above the safe exposure limit were estimated. Children were identified as the most vulnerable receptor. Therefore, there is an urgent need to establish effective regulations that guarantee the protection of river users in potentially contaminated areas. Finally, it is important to continue investigating the contamination caused by human practices in the coastal region.