Browsing by Autor "J. Chincheros"

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CONTAMINACION POR MERCURIO EN AGUA, PECES Y CABELLOS HUMANOS DEBIDO A LA MINERÍA AURÍFERA EN LA CUENCA AMAZÓNICA BOLIVIANA
(2013) Laurence Maurice; Irma Lucía Jaramillo Quiroga; Olaf Malm; J. Chincheros
MERCURY CONTAMINATION IN WATER, FISH AND HUMAN HAIR AS A RESULT OF GOLD MINING IN THE AMAZONIAN BASIN OF BOLIVIA Se presentan los primeros resultados sobre el contenido en mercurio en dos compartimentos bioticos (peces y cabellos humanos) de la cuenca Amazonica Boliviana con un en foque mas preciso en el area minera de los tributarios del rio Beni. Las concentraciones en mercurio analizado en los peces piscivoros varian en los rios Beni y Mamore desde 0.3-2.3 pg Hg g-1 y 0.4-2.1 pg Hg g- 1 respectivamente, a 0.3-5.2 pg Hg g-1 en la cabecera de! rio Madera. Los resultados mostraron que el 70% de los peces piscivoros colectados estan altamente contaminados ya que sobrepasan, hasta cinco veces, el valor limite de la OMS (1976) de 0.5 pg Hg g-1. El mercurio acumulado en los peces piscivoros esta principalmente en forma organica; el metilmercurio representa 70 a 100% del mercurio total. Los resultados tambien muestran que el mayor impacto del mercurio se manifiesta sobre la salud de la poblacion que no trabaja directamente en actividades auriferas, pero que se alimenta regularmente de pescado. Palabras clave: Mercurio, Cabellos humanos, Peces, Cuenca amazonica, Bolivia. ABSTRACT First results on the mercury concentration in twa biotic compartments (fish and human hair) from the goid mining area of the Bolivian Amazonian basin, SW Amazon, are presented. The mercury concentrations found in carnivorous fishes vary in the Beni River from 0.3 to 2.3 pg Hg g-1, in the Mamore River, from 0.4 to 2.1 pg Hg g-1, and in the Madeira River at its formation from 0.3 to 5.2 pg Hg g-i. This results indicate, on bne hand, that 70% of the piscivorous fishes collected is contaminated and on the other hand, that high mercury concentrations can nearly exceed 5 times the WHO (1976) safety limit (0.5 pg Hg g-l). The mercury accumulated by carnivorous fishes is mainly present on its organic form effectively, methylmercury represents 70 fo 100% of the total mercury analysed. Our results show that the major health impact caused by mercury affects people who are not working directly in gold cooperatives but who have a fish diet. Key words: Mercury, Human hair, Fish, Amazonian basin, Bolivia
Hg Speciation and Stable Isotope Signatures in Human Hair As a Tracer for Dietary and Occupational Exposure to Mercury
(American Chemical Society, 2011) Laure Laffont; Jeroen E. Sonke; Laurence Maurice; Selma Luna-Monrroy; J. Chincheros; David Amouroux; Philippe Behra
Exposure of humans and wildlife to various inorganic and organometallic forms of mercury (Hg) may induce adverse health effects. While human populations in developed countries are mainly exposed to marine fish monomethylmercury (MMHg), this is not necessarily the case for developing countries and diverse indigenous people. Identification of Hg exposure sources from biomonitor media such as urine or hair would be useful in combating exposure. Here we report on the Hg stable isotope signatures and Hg speciation in human hair across different gold miner, indigenous and urban populations in Bolivia and France. We found evidence for both mass-dependent isotope fractionation (MDF) and mass-independent isotope fractionation (MIF) in all hair samples. Three limiting cases of dominant exposure to inorganic Hg (IHg), freshwater fish MMHg, and marine fish MMHg sources are used to define approximate Hg isotope source signatures. Knowing the source signatures, we then estimated Hg exposure sources for the Bolivian gold miner populations. Modeled IHg levels in hair correspond well to measured IHg concentrations (R = 0.9), demonstrating that IHg exposure sources to gold miners can be monitored in hair samples following either its chemical speciation or isotopic composition. Different MMHg and inorganic exposure levels among gold miners appear to correspond to living and working conditions, including proximity to small towns, and artisanal vs large scale mining activity.
How Uncontrolled Urban Expansion Increases the Contamination of the Titicaca Lake Basin (El Alto, La Paz, Bolivia)
(Springer Science+Business Media, 2016) Denisse Archundia; Céline Duwig; Lorenzo Spadini; Gaëlle Uzu; Stéphane Guédron; Marie‐Christine Morel; R. Cortez; Oswaldo Ramos Ramos; J. Chincheros; Jean Martins
Impacts of Anthropogenic Activities on the Contamination of a Sub Watershed of Lake Titicaca. Are Antibiotics a Concern in the Bolivian Altiplano?
(Elsevier BV, 2014) Céline Duwig; Denisse Archundia; Frédéric Lehembre; Lorenzo Spadini; Marie‐Christine Morel; Gaëlle Uzu; J. Chincheros; R. Cortez; Jean Martins
The Titicaca Lake is the most important water resource over the Andean plateau and the ecological equilibrium of this region is nowadays perturbed by recent changes in land use and management practices. The Katari watershed encompasses mining area, cities representing over 1.2 million habitants, and agricultural zones before ending in Cohana bay in the Titicaca Lake. Cohana Bay is known to be one of the most eutrophic bay of the Titicaca Lake. The objective of the study was to evaluate the impact of anthropic activities along the watershed on the river quality and on the bacterial diversity. Both mining activities and release of wastewater in river systems impacts greatly the surface water quality, with level of As exceeding limits for drinking water, and phosphate over the European guidelines for bad quality rivers. Antibiotic from the sulfonamide family was detected in the watershed in high concentrations downstream of the two main cities and bacterial resistance occurred in nearly all the sampled water points.