Expansion of small-scale gold mining in Madre de Dios: ‘capital interests’ and the emergence of a new elite of entrepreneurs in the Peruvian Amazon

Context: Gold mining is the most destructive activity in the natural forests of the Madre de Dios region in the southeastern Peruvian Amazon. Understanding the natural regeneration process of these degraded areas is necessary to develop forest restoration projects in such conditions.Aims: We aimed to evaluate forest recovery and identify the successional and structure patterns of vegetation governing natural regeneration over time.Methods: Structure, composition, richness, diversity, and successional status were evaluated in abandoned artisanal gold mine areas in Madre de Dios, southeastern Peru. Vegetation data were recorded in 61 plots of 250 m2 established in five sites varying from 1 to 19 years of abandonment. Vegetation in abandoned areas was compared with six undisturbed forests evaluated in previous inventories.Results: In the mining lands, tree density and basal area recovered quickly, while species richness and composition were slow. Forest recovery is an initial stage of transition from pioneer to early secondary species until at least 19 years after abandonment. The most abundant and frequent species were the fast-growing species Ochroma pyramidale and Cecropia engleriana. These species could be considered potential candidates to promote restoration plans. Pioneer species represented 63% of the number of species in plots of 1–4 years, 57% in plots of 5–7 years, and 50% in plots of 8–19 years. Early and late secondary species represented 34 and 16%, respectively, of the number of species in plots of 8–19 years. Abandoned mining and reference plots present less than 5% of species in common.Conclusion: Our results highlight a slow natural regeneration process in areas for up to 19 years after gold mining. Species from different successional statuses were identified as potential candidates for recovering vegetation in such areas. Our findings may have important implications for further research focusing on the ecological restoration in tropical forests severely degraded by gold mining.

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Mercury Levels in Human Hair and Farmed Fish near Artisanal and Small-Scale Gold Mining Communities in the Madre de Dios River Basin, Peru

10.20944/preprints201703.0076.v1 ◽

2017 ◽

Author(s):

Aubrey L. Langeland ◽

Rebecca D. Hardin ◽

Richard L. Neitzel

Keyword(s):

River Basin ◽

Gold Mining ◽

Total Mercury ◽

Mercury Level ◽

Mercury Exposure ◽

Small Scale ◽

Farmed Fish ◽

Mining Communities ◽

Hair Mercury ◽

Madre De Dios

Artisanal and small-scale gold mining (ASGM) has been an important source of income for communities in the Madre de Dios River Basin in Peru for hundreds of years. However, in recent decades, the scale of ASGM activities in the region has increased dramatically, and exposures to a variety of occupational and environmental hazards related to ASGM, including mercury, are becoming more widespread. The aims of our study were to: (1) examine patterns in the total hair mercury level of human participants in several communities in the region and compare these results to the 2.2 µg/g total hair mercury level equivalent to the World Health Organization (WHO) Expert Committee of Food Additives (JECFA)’s Provisional Tolerable Weekly Intake (PTWI); and (2), to measure the mercury levels of paco (Piaractus brachypomus) fish raised in local aquaculture ponds, in order to compare these levels to the EPA Fish Tissue Residue Criterion of 0.3 µg Hg/g fish (wet weight). We collected hair samples from 80 participants in four communities (one control and three where ASGM activities occurred) in the region, and collected 111 samples from fish raised in 24 local aquaculture farms. We then analyzed the samples for total mercury. Total mercury levels in hair were statistically significantly higher in the mining communities than in the control community, and increased with increasing distance away from the Madre de Dios headwaters (as the crow flies), did not differ by sex, and frequently exceeded the reference level. Regression analyses indicated that higher hair mercury levels were associated with residence in ASGM communities. The analysis of paco fish samples found no samples that exceeded the EPA tissue residue criterion. Collectively, these results align with other recent studies showing that ASGM activities are associated with elevated human mercury exposure. The fish farmed through the relatively new process of aquaculture in ASGM areas appeared to have little potential to contribute to human mercury exposure. More research is needed on human health risks associated with ASGM to discern occupational, residential, and nutritional exposure, especially through tracking temporal changes in mercury levels as fish ponds age, and assessing levels in different farmed fish species. Additionally, research is needed to definitively determine that elevated mercury levels in humans and fish result from the elemental mercury from mining, rather than from a different source, such as the mercury released from soil erosion during deforestation events from mining or other activities.

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River transport of mercury from artisanal and small-scale gold mining and risks for dietary mercury exposure in Madre de Dios, Peru

Environmental Science Processes & Impacts ◽

10.1039/c4em00567h ◽

2015 ◽

Vol 17 (2) ◽

pp. 478-487 ◽

Cited By ~ 45

Author(s):

Sarah E. Diringer ◽

Beth J. Feingold ◽

Ernesto J. Ortiz ◽

John A. Gallis ◽

Julio M. Araújo-Flores ◽

...

Keyword(s):

Gold Mining ◽

Mercury Exposure ◽

Small Scale ◽

Environmental Sampling ◽

Madre De Dios ◽

River Transport ◽

Downstream Communities

Environmental sampling over 560 km of the Madre de Dios River indicated a gradient of mercury exposure from areas of active mining to downstream communities.

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Efficacy of Hair Total Mercury Content as a Biomarker of Methylmercury Exposure to Communities in the Area of Artisanal and Small-Scale Gold Mining in Madre de Dios, Peru

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph182413350 ◽

2021 ◽

Vol 18 (24) ◽

pp. 13350

Author(s):

Faye Koenigsmark ◽

Caren Weinhouse ◽

Axel Berky ◽

Ana Morales ◽

Ernesto Ortiz ◽

...

Keyword(s):

Gold Mining ◽

Total Mercury ◽

Large Population ◽

Inorganic Mercury ◽

Mercury Content ◽

Mercury Exposure ◽

Small Scale ◽

Population Exposure ◽

Mehg Exposure ◽

Madre De Dios

Total mercury content (THg) in hair is an accepted biomarker for chronic dietary methylmercury (MeHg) exposure. In artisanal and small-scale gold mining (ASGM) communities, the validity of this biomarker is questioned because of the potential for contamination from inorganic mercury. As mining communities may have both inorganic and organic mercury exposures, the efficacy of the hair-THg biomarker needs to be evaluated, particularly as nations begin population exposure assessments under their commitments to the Minamata Convention. We sought to validate the efficacy of hair THg for public health monitoring of MeHg exposures for populations living in ASGM communities. We quantified both THg and MeHg contents in hair from a representative subset of participants (N = 287) in a large, population-level mercury exposure assessment in the ASGM region in Madre de Dios (MDD), Peru. We compared population MeHg-THg correlations and %MeHg values with demographic variables including community location, sex, occupation, and nativity. We observed that hair MeHg-THg correlations were high (r > 0.7) for all communities, regardless of location or nativity. Specifically, for individuals within ASGM communities, 81% (121 of 150 total) had hair THg predominantly in the form of MeHg (i.e., >66% of THg) and reflective of dietary exposure to mercury. Furthermore, for individuals with hair THg exceeding the U.S. EPA threshold (1.0 μg/g), 88 out of 106 (83%) had MeHg as the predominant form. As a result, had urine THg solely been used for mercury exposure monitoring, approximately 59% of the ASGM population would have been misclassified as having low mercury exposure. Our results support the use of hair THg for monitoring of MeHg exposure of populations in ASGM settings where alternative biomarkers of MeHg exposure are not feasible.

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Mercury Exposure In Madre De Dios, Peru: Connecting Environmental Contamination To Human Exposure In A Region Of Small Scale Gold Mining

ISEE Conference Abstracts ◽

10.1289/isee.2015.2015-3484 ◽

2015 ◽

Vol 2015 (1) ◽

pp. 3484

Author(s):

Beth J. Feingold ◽

Helen Hsu-Kim ◽

Kaitlin Porter ◽

Ernesto Ortiz ◽

Laura Rogers ◽

...

Keyword(s):

Environmental Contamination ◽

Human Exposure ◽

Gold Mining ◽

Mercury Exposure ◽

Small Scale ◽

Madre De Dios

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Mercury Contamination in Riverine Sediments and Fish Associated with Artisanal and Small-Scale Gold Mining in Madre de Dios, Peru

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph15081584 ◽

2018 ◽

Vol 15 (8) ◽

pp. 1584 ◽

Cited By ~ 20

Author(s):

Gerardo Martinez ◽

Stephen McCord ◽

Charles Driscoll ◽

Svetoslava Todorova ◽

Steven Wu ◽

...

Keyword(s):

Gold Mining ◽

Trophic Position ◽

Mercury Contamination ◽

Food Sources ◽

Small Scale ◽

Habitat Conditions ◽

Ecological Processes ◽

Madre De Dios ◽

Fish Samples ◽

Δ15n And Δ13c

Artisanal and small-scale gold mining (ASGM) in Madre de Dios, Peru, continues to expand rapidly, raising concerns about increases in loading of mercury (Hg) to the environment. We measured physicochemical parameters in water and sampled and analyzed sediments and fish from multiple sites along one ASGM-impacted river and two unimpacted rivers in the region to examine whether Hg concentrations were elevated and possibly related to ASGM activity. We also analyzed the 308 fish samples, representing 36 species, for stable isotopes (δ15N and δ13C) to estimate their trophic position. Trophic position was positively correlated with the log-transformed Hg concentrations in fish among all sites. There was a lack of relationship between Hg concentrations in fish and either Hg concentrations in sediments or ASGM activity among sites, suggesting that fish Hg concentrations alone is not an ideal bioindicator of site-specific Hg contamination in the region. Fish Hg concentrations were not elevated in the ASGM-impacted river relative to the other two rivers; however, sediment Hg concentrations were highest in the ASGM-impacted river. Degraded habitat conditions and commensurate shifts in fish species and ecological processes may influence Hg bioaccumulation in the ASGM-impacted river. More research is needed on food web dynamics in the region to elucidate any effects caused by ASGM, especially through feeding relationships and food sources.

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Digging into the Mining Subculture: The Dynamics of Trafficking in Persons in the Artisanal and Small-Scale Gold Mining of Peru’s Madre de Dios

Illegal Mining ◽

10.1007/978-3-030-46327-4_13 ◽

2020 ◽

pp. 359-386

Author(s):

Dolores Cortés-McPherson

Keyword(s):

Gold Mining ◽

Small Scale ◽

Trafficking In Persons ◽

Madre De Dios

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Growth and survivorship of Vetiveria zizanioides in degraded soil by gold-mining in the Peruvian Amazon

Journal of Degraded and Mining Lands Management ◽

10.15243/jdmlm.2021.091.3219 ◽

2021 ◽

Vol 9 (1) ◽

pp. 3219-3225

Author(s):

Jorge Santiago Garate Quispe ◽

Rosa Ponce de Leon ◽

Marx Herrera Machaca ◽

Edgar Julian Laime ◽

Carlos Nieto Ramos

Keyword(s):

Forest Soil ◽

Gold Mining ◽

Block Design ◽

Univariate Analysis ◽

Small Scale ◽

Total Biomass ◽

Peruvian Amazon ◽

Vetiveria Zizanioides ◽

Significant Difference ◽

Amended Soil

In the Peruvian Amazon, large area of primary forest have been deforested by Artisanal and small-scale gold mining (ASGM). Vetiveria zizanioides (Poaceae) is considered an excellent plant for the ecological restoration of degraded lands. The present study aimed to analyze the growth and survivorship of V. zizanioides in degraded soils by gold-mining in the Peruvian Amazon (Madre de Dios). The experiment was conducted under greenhouse conditions, and it followed a randomized complete block design with four treatments (substrates). The substrates were sand (mining), sand+pebbles (mining), forest soil, and amended soil. We evaluated the survivorship, shoot, tiller, and biomass production of V. zizanioides for two months. Univariate analysis of variance was used to detect differences among treatments. Fifteen days after experiment establishment, V. zizanioides survivorship was significantly higher in ASGM substrate 2 (sand+pebbles) than in other substrates, following the order of ASGM substrate 1 (sand) > forest soil > amended soil. However, at the end of the experiment, we did not find a significant difference on survivorship in subsequent assessments, and the total biomass per plant was lower in mining substrates than in non-mining substrates. The total biomass was significantly higher in amended soil than in other substrates, with yields between 1.7 and 3.6 times more biomass in amended substrate than in mine substrates. The soil substrate type significantly affected the survivorship, number of shoots, and biomass of V. zizanioides. The research results can provide a reference for remediation of degraded soils by gold-mining in the Peruvian Amazon.

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