Claudia Vega - Academia.edu (original) (raw)

Papers by Claudia Vega

Research paper thumbnail of Intake of predatory fish in Amazonia is a driver of toxicological risk for susceptible exposure groups

E3S web of conferences, 2013

Research paper thumbnail of Amazon forests capture high levels of atmospheric mercury pollution from artisanal gold mining

Nature Communications, 2022

Mercury emissions from artisanal and small-scale gold mining throughout the Global South exceed c... more Mercury emissions from artisanal and small-scale gold mining throughout the Global South exceed coal combustion as the largest global source of mercury. We examined mercury deposition and storage in an area of the Peruvian Amazon heavily impacted by artisanal gold mining. Intact forests in the Peruvian Amazon near gold mining receive extremely high inputs of mercury and experience elevated total mercury and methylmercury in the atmosphere, canopy foliage, and soils. Here we show for the first time that an intact forest canopy near artisanal gold mining intercepts large amounts of particulate and gaseous mercury, at a rate proportional with total leaf area. We document substantial mercury accumulation in soils, biomass, and resident songbirds in some of the Amazon’s most protected and biodiverse areas, raising important questions about how mercury pollution may constrain modern and future conservation efforts in these tropical ecosystems.

Research paper thumbnail of Identifying Sources of Mercury in Peruvian Amazon Aquatic Systems Using Hg Stable Isotopes

Goldschmidt Abstracts, 2020

Research paper thumbnail of Oxidative Stress Levels Induced by Mercury Exposure in Amazon Juvenile Populations in Brazil

International Journal of Environmental Research and Public Health, 2019

Oxidative stress can be induced by mercury (Hg) exposure, including through fish consumption (die... more Oxidative stress can be induced by mercury (Hg) exposure, including through fish consumption (diet), leading to health risks. The objective of this study was to evaluate the association between oxidative stress biomarkers and dietary Hg exposure levels in riverine children and adoluiaescents at Madeira River (RO/Brazil). Population from three riverine local communities presenting different fish consumption frequencies was sampled. Hg was determined in blood (ICP-MS) and glutathione (GSH); glutathione S-transferases (GST) and malondialdehyde (MDA) were determined in serum (spectrophotometry). Statistical analyses were performed using parametric and non-parametric tests. Multiple linear regression models and generalized additives models were also used to estimate the relationships between oxidative stress biomarkers and blood Hg. The juvenile riverine population from Cuniã RESEX presented the highest levels of oxidative stress and Hg levels in blood (GST = 27.2 (4.93) U/L, MDA = 1.69 ...

Research paper thumbnail of 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, Jul 26, 2018

Artisanal and small-scale gold mining (ASGM) in Madre de Dios, Peru, continues to expand rapidly,... more 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 (δN and δC) 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 i...

Research paper thumbnail of Human Mercury Exposure in Yanomami Indigenous Villages from the Brazilian Amazon

International journal of environmental research and public health, May 23, 2018

In the Brazilian Amazon, where the majority of Yanomami villages are settled, mercury (Hg) exposu... more In the Brazilian Amazon, where the majority of Yanomami villages are settled, mercury (Hg) exposure due to artisanal small-scale gold mining (ASGM) has been reported since the 1980s. This study assessed mercury exposure in the Yanomami reserve and whether the level of contamination was related to the ASGM geographical location. It was conducted using a cross-sectional study of 19 villages. Direct interviews were performed and hair samples were used as a bioindicator of Hg exposure. The Prevalence-Ratio (PR) was estimated as an indicator of association between ASGM geographical locations and human exposure to mercury. Mercury levels (239 hair samples) ranged between 0.4 and 22.1 μg·g and presented substantial differences amongst the villages. In the Waikas-Aracaça region, where current ASGM was reported, we observed the highest Hg concentrations (median = 15.5 μg·g). Almost all participants presented with hair-Hg levels >6 μg·g (prevalence = 92.3%). In the Paapiu region, we observ...

Research paper thumbnail of Health Assessment of Mercury Exposure in a Riparian Community in the Madeira River

E3S Web of Conferences, 2013

Research paper thumbnail of Tracing Atmospheric Mercury in the Peruvian Amazon Using Hg Isotopes

Goldschmidt Abstracts, 2020

Research paper thumbnail of Method for mapping Hg0 emissions from gold shops in artisanal and small-scale gold mining communities

MethodsX, 2020

Gold shops in artisanal and small-scale gold mining communities represent major point sources of ... more Gold shops in artisanal and small-scale gold mining communities represent major point sources of airborne mercury pollution. Concentrations of elemental mercury (Hg 0) emitted by these shops can be determined using a portable atomic absorbance spectrometer (AAS) with Zeeman correction. These measured Hg 0 concentrations can then be correlated to position as determined by a hand-held GPS unit, and the resulting data mapped using a Geographic Information System (GIS). A detailed method for obtaining and analyzing data collected near gold shops in Mazuko, Peru is provided. Maps generated using this method were employed to identify point sources of Hg 0 contamination originating from gold shops in ASGM communities and were shared with local city managers to assist in urban planning. • A detailed method is provided to collect and process data, ultimately generating a map that allows for the screening of a community to identify point sources of Hg 0 contamination. • Raw data is provided, as well as a video detailing data processing and mapping using a common spreadsheet program and an open-source GIS. • The generated map can be used for determining areas where people may be exposed to elevated Hg 0 concentrations and/or occupational mercury vapor exposure, targeted enforcement, or outreach to limit Hg 0 pollution.

Research paper thumbnail of Intake of predatory fish in Amazonia is a driver of toxicological risk for susceptible exposure groups

E3S web of conferences, 2013

Research paper thumbnail of Amazon forests capture high levels of atmospheric mercury pollution from artisanal gold mining

Nature Communications, 2022

Mercury emissions from artisanal and small-scale gold mining throughout the Global South exceed c... more Mercury emissions from artisanal and small-scale gold mining throughout the Global South exceed coal combustion as the largest global source of mercury. We examined mercury deposition and storage in an area of the Peruvian Amazon heavily impacted by artisanal gold mining. Intact forests in the Peruvian Amazon near gold mining receive extremely high inputs of mercury and experience elevated total mercury and methylmercury in the atmosphere, canopy foliage, and soils. Here we show for the first time that an intact forest canopy near artisanal gold mining intercepts large amounts of particulate and gaseous mercury, at a rate proportional with total leaf area. We document substantial mercury accumulation in soils, biomass, and resident songbirds in some of the Amazon’s most protected and biodiverse areas, raising important questions about how mercury pollution may constrain modern and future conservation efforts in these tropical ecosystems.

Research paper thumbnail of Identifying Sources of Mercury in Peruvian Amazon Aquatic Systems Using Hg Stable Isotopes

Goldschmidt Abstracts, 2020

Research paper thumbnail of Oxidative Stress Levels Induced by Mercury Exposure in Amazon Juvenile Populations in Brazil

International Journal of Environmental Research and Public Health, 2019

Oxidative stress can be induced by mercury (Hg) exposure, including through fish consumption (die... more Oxidative stress can be induced by mercury (Hg) exposure, including through fish consumption (diet), leading to health risks. The objective of this study was to evaluate the association between oxidative stress biomarkers and dietary Hg exposure levels in riverine children and adoluiaescents at Madeira River (RO/Brazil). Population from three riverine local communities presenting different fish consumption frequencies was sampled. Hg was determined in blood (ICP-MS) and glutathione (GSH); glutathione S-transferases (GST) and malondialdehyde (MDA) were determined in serum (spectrophotometry). Statistical analyses were performed using parametric and non-parametric tests. Multiple linear regression models and generalized additives models were also used to estimate the relationships between oxidative stress biomarkers and blood Hg. The juvenile riverine population from Cuniã RESEX presented the highest levels of oxidative stress and Hg levels in blood (GST = 27.2 (4.93) U/L, MDA = 1.69 ...

Research paper thumbnail of 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, Jul 26, 2018

Artisanal and small-scale gold mining (ASGM) in Madre de Dios, Peru, continues to expand rapidly,... more 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 (δN and δC) 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 i...

Research paper thumbnail of Human Mercury Exposure in Yanomami Indigenous Villages from the Brazilian Amazon

International journal of environmental research and public health, May 23, 2018

In the Brazilian Amazon, where the majority of Yanomami villages are settled, mercury (Hg) exposu... more In the Brazilian Amazon, where the majority of Yanomami villages are settled, mercury (Hg) exposure due to artisanal small-scale gold mining (ASGM) has been reported since the 1980s. This study assessed mercury exposure in the Yanomami reserve and whether the level of contamination was related to the ASGM geographical location. It was conducted using a cross-sectional study of 19 villages. Direct interviews were performed and hair samples were used as a bioindicator of Hg exposure. The Prevalence-Ratio (PR) was estimated as an indicator of association between ASGM geographical locations and human exposure to mercury. Mercury levels (239 hair samples) ranged between 0.4 and 22.1 μg·g and presented substantial differences amongst the villages. In the Waikas-Aracaça region, where current ASGM was reported, we observed the highest Hg concentrations (median = 15.5 μg·g). Almost all participants presented with hair-Hg levels >6 μg·g (prevalence = 92.3%). In the Paapiu region, we observ...

Research paper thumbnail of Health Assessment of Mercury Exposure in a Riparian Community in the Madeira River

E3S Web of Conferences, 2013

Research paper thumbnail of Tracing Atmospheric Mercury in the Peruvian Amazon Using Hg Isotopes

Goldschmidt Abstracts, 2020

Research paper thumbnail of Method for mapping Hg0 emissions from gold shops in artisanal and small-scale gold mining communities

MethodsX, 2020

Gold shops in artisanal and small-scale gold mining communities represent major point sources of ... more Gold shops in artisanal and small-scale gold mining communities represent major point sources of airborne mercury pollution. Concentrations of elemental mercury (Hg 0) emitted by these shops can be determined using a portable atomic absorbance spectrometer (AAS) with Zeeman correction. These measured Hg 0 concentrations can then be correlated to position as determined by a hand-held GPS unit, and the resulting data mapped using a Geographic Information System (GIS). A detailed method for obtaining and analyzing data collected near gold shops in Mazuko, Peru is provided. Maps generated using this method were employed to identify point sources of Hg 0 contamination originating from gold shops in ASGM communities and were shared with local city managers to assist in urban planning. • A detailed method is provided to collect and process data, ultimately generating a map that allows for the screening of a community to identify point sources of Hg 0 contamination. • Raw data is provided, as well as a video detailing data processing and mapping using a common spreadsheet program and an open-source GIS. • The generated map can be used for determining areas where people may be exposed to elevated Hg 0 concentrations and/or occupational mercury vapor exposure, targeted enforcement, or outreach to limit Hg 0 pollution.