Artisanal Small-scale Gold Mining Communities Research Articles

Correction to: Emerging mercury mitigation solutions for artisanal small-scale gold mining communities evaluated through a multicriteria decision analysis approach

Correction to: Emerging mercury mitigation solutions for artisanal small-scale gold mining communities evaluated through a multicriteria decision analysis approach

Socio-environmental perceptions and barriers to conservation engagement among artisanal small-scale gold mining communities in Southeastern Peru

Artisanal small-scale gold mining (ASGM) poses threats to biodiversity and to the health and well-being of human communities. However, ASGM also economically supports several populations from lower social-economic backgrounds, especially in the Global South. In Madre de Dios (MDD), Peru, ASGM is the most significant economic activity, involving several stakeholders form different levels of governance. To protect this area’s forests and aquatic systems from further degradation, it is necessary to understand the socio-economic background and the impediments to mining formalization, as well as the local perceptions and willingness to engage in conservation. In this study, we aimed to establish the drivers of and barriers to participation in environmental conservation among communities in MDD, which economically rely on ASGM. Using a mixed method approach, we surveyed 85 households in six communities in the MDD gold corridor. Half of participants were cognizant of the effects of ASGM and concerned about deforestation and local decreases in fish and wildlife abundance, declaring willingness to take part in environmental conservation. Native participants in particular expressed concern about land degradation and the action of immigrants. However, several participants reported feeling alienated by government institutions and raised doubts about the intentions of non-governmental conservation organizations, and the purpose of protected areas. Participants in general felt that ASGM-related policies were not realistic and bureaucratic barriers were raised to prevent formalization. Our findings suggest that current policies and communication strategies may hinder efforts to transform relatively prevalent pro-environmental attitudes into matching behaviors, including participation in conservation initiatives. To achieve this goal, more efficient communication and more active involvement of local stakeholders in mining governance and conservation planning are necessary.

Emerging mercury mitigation solutions for artisanal small-scale gold mining communities evaluated through a multicriteria decision analysis approach

Over 15 million people are involved in artisanal small-scale gold mining (ASGM) globally. Often, ASGM includes smelters that use mercury to extract gold. If mishandled, these actions may cause adverse health effects for smelters and their surrounding communities. There are multiple tools to reduce health risks while maintaining a sustainable economic profit, but each method has trade-offs, such as cost, efficiency, and potential health impacts that are not widely understood. Multicriteria decision analysis (MCDA) is a powerful tool in assessing multiple perspectives and factors that affect stakeholder decisions and can be used to inform smelters and community members on reducing exposure to mercury. Here, MCDA was used to determine the ranks of alternatives to reduce exposure to mercury based on socio-economic, ecological, and human health criteria. Stochastic processes were used to evaluate 12 alternatives, including mitigation strategies (i.e., chelation therapy techniques, retorts, water filters) as well as mercury-free mining substitutes. In this model, the borax method ranked first 72% of the time, followed by the gravity method (19%), a multicapture system retort (7%), and low-cost retorts (≤ 1%). While MCDA is an excellent tool, results tend to be generalized across a heterogenous landscape. More localized factors such as incorrect soil chemistry could cause performance challenges for options like mercury-free mining substitutes. To aid more localized decision-making, a decision tree model was developed to aid stakeholders to explore which alternatives are suitable based on context-specific factors using “Take-the-best” decision heuristics. This work can assist researchers and stakeholders involved with ASGM to identify which options are scalable for their region as well as to mitigate adverse effects of exposure to mercury.

Modeling exposure risk and prevention of mercury in drinking water for artisanal-small scale gold mining communities

The goal of this study was to evaluate the age-differentiated health risks associated with exposure to mercury in drinking water from artisanal small-scale gold mining (ASGM) sites on nearby communities in Yolombo, Colombia. In 2017, nine samples were collected from a local regulatory agency to report mercury concentrations in locations near mining sites. We performed a risk assessment to find 100% of the water samples collected downstream of mining sites exceed Hazard Quotient (HQ) risk thresholds (set by the US-Environmental Protection Agency and Health Canada). HQ model, coupled with global sensitivity and uncertainty analysis (GSUA), was used to conclude infants as the most vulnerable, with 50% of the population exceeding HQ thresholds. Length of exposure was the most significant input that contributed to risk variance, explaining 30-55% of risk across all age groups. Monte-Carlo filtering was used to identify effective strategies to reduce the number of individuals exceeding allowable HQ thresholds. After Monte-Carlo filtering intervention strategies, all individuals are below HQ thresholds. This work shows the importance of combining risk assessment tools with sensor data to inform the need for filters, stakeholder education, and alternative mining approaches to gain a multi-perspective risk approach. This work provides a valuable risk and decision modeling methodology and baseline information to gain a deeper understanding of the probability of experiencing detrimental health effects from water contamination in ASGM communities.

Occupational human exposure to mercury in artisanal small-scale gold mining communities of Colombia

With the aim of protecting human life and the environment, the Minamata Convention seeks to reduce and monitor mercury (Hg) concentrations in the environment. 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 occupational exposure to Hg in the most relevant ASGM communities of Colombia. Mercury concentrations in different biological matrices were related to several variables of interest such as age, gender, body mass index, fish consumption, exposure time, and specific occupational activities, such as amalgamation and amalgam burning. The median values of THg in blood (3.70 µg/L), urine (4.00 µg/L) and hair (1.37 mg/kg), and hair MeHg (1.47 mg/kg) for all participants were below permissible concentrations set by WHO. However, about 40% of the miners showed Hg concentrations in blood, urine and/or hair above the WHO thresholds. In all the biological matrices studied, miners burning amalgams showed significantly higher concentrations than miners who did not burn amalgams, with values 7-, 7-, and 8-fold higher in blood, urine and hair, respectively. A multiple linear regression model revealed that burning amalgam and fish consumption were significant predictors of Hg exposure in miners. Miners from Guainía had the highest concentrations in urine and hair, most likely due to the high manipulation and burning of amalgam, and a high fish consumption. In contrast, miners from Caldas showed the lowest Hg concentrations in all the biomarkers because they do not manipulate or burn amalgam, as well as reporting the lowest fish consumption. Our study also highlighted that gold miners exposure to Hg depends on their work practices. Therefore, the implementation of a health education programme on gold mining strategies is required, especially in Guaina, Vaupés, Córdoba, and Antioquia departments.

Human health risk assessment of exposure to indoor mercury vapour in a Ghanaian artisanal small-scale gold mining community

People living or working in and around artisanal small-scale gold mining communities can be exposed to mercury vapour, which may negatively affect their health. In this study, the human exposure to air borne mercury in an artisanal mining community in the Upper East region of Ghana was investigated using Lumex RA 915 M mercury analyser, an active sampler. The concentration of mercury in air was measured inside and outside households and was related to human health risk standards. For each household, one measurement was taken from outside and three from inside at different positions. About 91% of the households where amalgam burning was reported had concentrations higher than the USEPA reference dose of 300 ng m−3 whereas 64% of the households where amalgam burning was not reported exceeded the reference dose above. The maximal (upper) instrumental limit (50,000 ng m−3) was passed for the highest concentrations, so, the upper 97.5% concentration was estimated, using censored statistics, to exceed 800,000 ng m−3 for the fireplaces. This exceeds any reported indoor household air concentration of Hg, identified by the literature review in this paper. Estimated hazard quotients were found to range from <1 to 108 within the households that are reported not to burn amalgam. In the households where amalgam burning reportedly takes place, the hazard quotient had a range of 0.01–160. Mercury concentrations measured in households with reported amalgam burning are approximately ten times higher than those households with no reported burning of amalgam. The censored data predicted hazard quotients up to 966. The results indicate that both miners and non-miners of the community are at risk of adverse health effects resulting from inhalation of mercury vapour.

Dietary human exposure to mercury in two artisanal small-scale gold mining communities of northwestern Colombia

Artisanal and small-scale gold mining (ASGM) is the largest anthropogenic source of mercury pollution worldwide, posing a grave threat to human health. The present study identifies current levels of mercury in the human population from mining areas of the Chocó Department, Colombia, through total mercury (THg) and methylmercury (MeHg) measurements in human hair. Mercury exposure of the local population was assessed in two towns affected by ASGM and was related to different variables of interest. Concentrations of THg in human hair ranged from 0.06 to 17.54ppm and the mean value for the subjects under study was 2.48ppm. Men had significantly higher levels than women in both towns (3.29ppm vs. 0.77ppm). Fish consumption was related to a marked increase of THg in hair, with mean values close to five times higher in frequent fish consumers (5–7 times/week) than in non-fish consumers (4.80ppm vs. 0.90ppm). A multiple linear regression model was fitted successfully (R=0.671) and reveals that gender, fish consumption and location of residence were significant indicators of Hg levels in hair, while no significant relationship was found for age. Approximately 60% of subjects tested had THg levels that exceeded the U.S. Environmental Protection Agency reference dose of 1.0ppm, while 25% surpassed that of the World Health Organization (2.2ppm).

Effect of an educational intervention on occupational behaviors related to mercury use in artisanal small-scale gold mining communities

Effect of an educational intervention on occupational behaviors related to mercury use in artisanal small-scale gold mining communities

Mercury Exposure and Health Impacts among Individuals in the Artisanal and Small-Scale Gold Mining Community: A Comprehensive Review

Background: Mercury (Hg) is used in gold mining to extract gold from ore by forming “amalgam”—a mixture composed of approximately equal parts mercury and gold. Approximately 15 million people, including approximately 3 million women and children, participate in artisanal small-scale gold mining (ASGM) in developing countries. Thirty-seven percent of global air emissions of Hg are produced by ASGM. The recently adopted Minamata Convention calls for nations to gather health data, train health-care workers, and raise awareness in regard to ASGM activity.Objective: The purpose of our review was to evaluate the current literature regarding the health effects of Hg among those working and/or living in or near ASGM communities.Methods: We searched PubMed, ScienceDirect, and Google Scholar for studies relating to health effects and biomarkers of Hg exposure in ASGM communities. Articles published from 1990 through December 2012 were evaluated for relevance.Discussion: Studies reporting health assessments, kidney dysfunction, neurological disorders and symptoms, and immunotoxicity/autoimmune dysfunction in individuals living in or near an ASGM community were identified. More than 60 studies that measured biomarkers of Hg exposure in individuals living in or near ASGM communities were also identified. These studies, conducted in 19 different countries in South America, Asia, and Africa, demonstrated that hair and urine concentrations are well above World Health Organization health guidance values in ASGM communities.Conclusions: ASGM workers and their families are exposed to Hg vapor, and workers, workers’ families, and residents of nearby and downstream communities are consuming fish heavily contaminated with methylmercury.Citation: Gibb H, O’Leary KG. 2014. Mercury exposure and health impacts among individuals in the artisanal and small-scale gold mining community: a comprehensive review. Environ Health Perspect 122:667–672; http://dx.doi.org/10.1289/ehp.1307864