Probabilistic meta-analysis of risk from the exposure to Hg in artisanal gold mining communities in Colombia

Colombia is one of the largest per capita mercury polluters in the world as a consequence of its artisanal gold mining activities. The severity of this problem in terms of potential health effects was evaluated by means of a probabilistic risk assessment carried out in the twelve departments (or provinces) in Colombia with the largest gold production. The two exposure pathways included in the risk assessment were inhalation of elemental Hg vapors and ingestion of fish contaminated with methyl mercury. Exposure parameters for the adult population (especially rates of fish consumption) were obtained from nation-wide surveys and concentrations of Hg in air and of methyl-mercury in fish were gathered from previous scientific studies. Fish consumption varied between departments and ranged from 0 to 0.3 kg d?1. Average concentrations of total mercury in fish (70 data) ranged from 0.026 to 3.3 lg g?1. A total of 550 individual measurements of Hg in workshop air (ranging from menor queDL to 1 mg m?3) and 261 measurements of Hg in outdoor air (ranging from menor queDL to 0.652 mg m?3) were used to generate the probability distributions used as concentration terms in the calculation of risk. All but two of the distributions of Hazard Quotients (HQ) associated with ingestion of Hg-contaminated fish for the twelve regions evaluated presented median values higher than the threshold value of 1 and the 95th percentiles ranged from 4 to 90. In the case of exposure to Hg vapors, minimum values of HQ for the general population exceeded 1 in all the towns included in this study, and the HQs for miner-smelters burning the amalgam is two orders of magnitude higher, reaching values of 200 for the 95th percentile. Even acknowledging the conservative assumptions included in the risk assessment and the uncertainties associated with it, its results clearly reveal the exorbitant levels of risk endured not only by miner-smelters but also by the general population of artisanal gold mining communities in Colombia.

Probabilistic assessment of risk from the exposure to mercury in artisanal gold mining communities in Colombia

Colombia is one the largest per capita mercury polluters as a consequence of its artisanal gold mining operations, which are steadily increasing following the rising price of this metal. Compared to gravimetric separation methods and cyanidation, the concentration of gold using Hg amalgams presents several advantages: the process is less time-consuming and minimizes gold losses, and Hg is easily transported and inexpensive relative to the selling price of gold. Very often, mercury amalgamation is carried out on site by unprotected workers. During this operation large amounts of mercury are discharged to the environment and eventually reach the fresh water bodies in the vicinity where it is subjected to methylation. Additionally, as gold is released from the amalgam by heating on open charcoal furnaces in small workshops, mercury vapors are emitted and inhaled by the artisanal smelters and the general population

Ecoturismo Subacuático. Aplicación al Caso Particular de la Evaluación de un Sendero Submarino en las Costas de Maitencillo, V Región, Valparaíso, Chile.

La siguiente tesis nace a partir de la implementación de la actividad de buceo deportivo en el año 2002 en la Caleta de pescadores artesanales de Maitencillo, quinta región, Chile. Los pescadores administran, para su explotación, un tipo de área marina protegida llamada área de manejo y explotación de recursos bentónicos (AMERB), por lo que se hizo indispensable implementar un Plan de Gestión para el buceo deportivo con la finalidad de regular y controlar la actividad para proteger los recursos existentes en el área, sus ecosistemas y su biodiversidad. Para ello, se construyó un Sendero Submarino con 3 circuitos para el buceo. La tesis contextualiza el desarrollo y ejecución del proyecto y evalúa el Plan de Gestión y la utilización del Sendero Submarino y, para ello, se desarrolla una metodología para el cálculo de la capacidad de carga del Sendero y para la evaluación del Plan de Gestión, a través de indicadores biofísicos, socioeconómicos y de gobernabilidad. Esta tesis plantea un modelo de desarrollo a partir del principio del Ecodesarrollo, destacando, principalmente, que es la comunidad local de pescadores artesanales quien ejecuta y administra el proyecto, sin necesidad de recurrir a operadores privados de buceo y, por tanto, logrando para si los beneficios y el control de la actividad; por otro lado, destaca también que es una actividad a baja escala, con bajos impactos ambientales y por tanto sustentable y replicable para otras organizaciones de pescadores. Los resultados indican que con la información biofísica obtenida se pueden tomar medidas de gestión para la actividad de buceo de acuerdo al estado de los recursos bentónicos principales explotados por los pescadores, ya sea restringiendo la actividad, o suspendiéndola por algún período. Los resultados muestran que la cantidad de buceadores que utilizan el Sendero Submarino está muy por debajo de la capacidad de carga calculada, lo que hace que la presión de esta actividad sobre los recursos y el ecosistema marino sea muy baja. Los resultados socioeconómicos y de gobernabilidad indican que esta actividad ha generado ingresos adicionales para los pescadores que trabajan en esta actividad y también ha generado nuevos puestos de trabajo; además, la organización sindical se ha ido fortaleciendo al crear la comisión de ecoturismo y dar responsabilidades a otros pescadores en la gestión de la actividad. La tesis confirma la hipótesis de que “Los Senderos Submarinos pueden ser una forma de turismo sostenible en áreas marinas protegidas”. The present thesis is based on the implementation of scuba diving activities in the year 2002, in the local fishing cove of Maitencillo, Fifth region, Chile. The local fishermen manage the exploitation process of a type of protected marine area called benthic resource management and exploitation area (BRMEA); for this reason, the implementation of a Management programme for scuba diving to regulate and control this activity to protect the resources in the area, their ecosystems and biodiversity, became a priority. In 2002, an Underwater Path was built, with three tracks for scuba diving practice. This thesis contextualises the development and implementation of the Management programme and the use of the Underwater Path. It also develops a methodology to calculate the payload for the Underwater Path, and to assess the Management project through biophysical, economic and governance indicators. This thesis also proposes a development model by the principle of Sustainable development, with the local community of fishermen implementing and handling the project, without the intervention of private diving agencies, generating economic and social benefits, keeping environmental impact to a minimum level, and making it sustainable and worth emulating for other fishermen organisations. The results indicate, through the biophysical data obtained, that it is possible to take managerial measures regarding the scuba diving activity, according to the state of the most exploited benthic resources, by either restricting the activity or plainly suspending it for some time. The results show that the amount of divers using the Underwater path are way below the calculated payload, which keeps the strain that scuba diving causes on these resources and marine ecosystem to the minimum. The results of the socioeconomic and governance issues indicate that this activity has generated additional profits for the fishermen working in this activity, and also new jobs. Furthermore, the syndicate has strengthened thanks to the creation of an ecotourism commission and by assigning other local fishermen with responsibilities in the organisation of the activity. The thesis confirms the hypothesis that states, “Underwater Paths can become a form of sustainable tourism in protected marine areas”

Perspectiva jurídica de la gestión y conservación de los recursos pesqueros en España. La pesca-turismo como opción de futuro

El objetivo de la presente Tesis está dirigido a analizar diversas opciones de diversificación que la pesca marítima profesional puede tener, poniendo el acento en el respeto al medio ambiente. En concreto la Pesca-turismo aparece como una de las alternativas más viables tanto por su respeto al medio ambiente como por su relativamente sencilla posibilidad de implantación en España. A fin de poder desarrollar la misma se proponen los cambios legislativos necesarios para su implantación en nuestro país procediéndose, para ello, al estudio de la situación actual de la actividad pesquera en nuestro país desde un punto de vista jurídico, con una especial consideración de la gestión y conservación de los recursos pesqueros. El estudio de su posible implantación en España, comienza analizando cuáles son las diferentes administraciones que influyen en dicha actividad y en qué medida lo hacen, tanto en el ámbito nacional como en el supranacional, con una especial referencia a la Unión Europea, así como la organización de las mismas. Acto seguido se procede al examen, tanto de la normativa sobre la materia, como de la jurisprudencia y la doctrina aplicables a la actividad de pesca marítima en España para, una vez llevado a cabo dicho estudio, comenzar con el examen de los requisitos exigidos, ya sean éstos de índole material o humana, a aquéllos que quieran llevarla a cabo. A continuación, se estudia el régimen de infracciones y sanciones, entrando, por último, en el terreno más propiamente de conservación de los recursos, donde se examinan las medidas que, a tal fin, se encuentran en nuestro ordenamiento jurídico. Más adelante se analiza, siquiera sea brevemente, la pesca deportiva, que, aunque con una incidencia muy inferior, no deja de ser otra forma de actividad extractiva. La existencia de otras experiencias parecidas a la propuesta de pesca-turismo en el ámbito internacional es objeto de estudio a fin de determinar cuál es la situación en otros países donde se hayan implantado con anterioridad. Para ello se lleva a cabo un análisis de las distintas soluciones que a este mismo problema se han dado en otros países también con amplia tradición en este campo procediendo, a tal fin, a un estudio de la legislación sobre la pesca-turismo, fundamentalmente en Italia, pero también en Francia y Portugal. A la vista de cuanto antecede es posible concluir que al día de hoy no es factible la realización de las actividades de Pesca-turismo con los instrumentos jurídicos de los que se dispone en España, dado que existen puntos sustanciales en los mismos que o bien impiden o bien no permiten su desarrollo. Por tanto el planteamiento de tales actividades necesariamente conlleva una serie de modificaciones normativas. El siguiente paso y en relación con las modificaciones normativas a efectuar, se ofrece un texto alternativo al texto legal a modificar (Ley 3/2001 de Pesca Marítima del Estado) y al Real Decreto 1027/1989, mientras que se dejan efectuados los apuntes precisos de cual debería de ser el marco reglamentario que, en desarrollo de las modificaciones anteriores, posibilitasen el ejercicio de la Pesca-turismo en España. Por último se ha optado por efectuar un análisis de la opinión del sector, tendente a verificar si los datos obtenidos empíricamente quedaban asimismo reflejados en las actitudes de los destinatarios finales de tales normas, que no serían otros que los pescadores profesionales. A tal fin se ha procedido a recoger las opiniones de diversos colectivos del sector, a través tanto de las cofradías de pescadores como de las Federaciones, acerca de las actividades de pesca-turismo, buscando la representación de todas las zonas geográficas. Fruto de tal investigación se ha llegado a la conclusión de que el desarrollo de las actividades propuesta de pescaturismo cuenta con una opinión favorable dentro del sector que, con una mayoría aplastante se manifestó a favor de desarrollar la posibilidad de ejercicio de la mismas. SUMMARY The objective of this thesis is aimed to analyze various options of diversification that commercial maritime fishing can have, with an emphasis on respect for the environment. Specifically, fishing-tourism appears as one of the most viable alternatives because of its environmental friendliness as well by its relatively simple possibility of implementation in Spain In order to develop it, it is proposed the necessary changes legislative for implementation in our country proceeding to study of the current situation of fisheries in our country from a legal perspective, with special consideration of the management and conservation of fisheries resources. The study of their possible implementation in Spain, begins by analyzing which are the different administrations that influence in that activity and to what extent they do, both at the national field as well at the supranational field, with special reference to the European Union and organization of thereof. Then proceeds to an examination, both of the relevant legislation as well as of the jurisprudence and doctrine applicable to maritime fishing in Spain for, once conducted this study, to begin with the consideration of the requirements, be they human or material, to those who want to carry out. Then studies the regime of offences and penalties, entering, finally, in the field conservation of resources, where discusses measures which, to this end, are in our legal system Later analyzes, even briefly, sport fishing, which, although with a much lower incidence, it is another form of extractive activity. The existence of other similar experiences to the proposal of fishing-tourism in the international arena is object of study in order to determine which is the situation in other countries where it has been implemented previously. For that it is carried out an analysis of the different solutions that to this same problem have been given in other countries with long tradition in this field, to proceed to study about legislation on fishing-tourism, fundamentally in Italy, but also in France and Portugal In view of the above it can be concluded that today is not feasible to implement the fishing-tourism activities with the legal instruments that are available in Spain, as there are substantial points which prevent them or not allows its development. Therefore the approach to such activities necessarily entails a series of normatives changes. The next step and in relation to normatives changes to do, it is offered an alternative text to the legal text to modify (Law 3/2001 of the State Marine Fisheries) and to the Royal Decree No. 1027 / 1989, while we leave made accurate notes about which ought be the reglamentary framework that, in developing of the above modifications, can be enable exercise of fishing-tourism in Spain. Finally, it is been opted to carry out an analysis of the opinion of the sector, aimed at verifying if data obtained empirically were also reflected in the attitudes of the final recipients of such standards, who would not be other than the professional fishermen. For this purpose it has been collected the opinions of various groups of the sector, through of fishermen's associations and federations, about of the activities of tourism-fishing, looking for the representation of all geographical areas. The result of such an investigation has concluded that the development of this proposed activities fishing-tourism has a positive opinion within the sector because an overwhelming majority was in favor of developing the possibility of exercise of the same.

Artisan procedures to generate uniform tilings

This paper try to prove how artisans c ould discover all uniform tilings and very interesting others us ing artisanal combinatorial pro cedures without having to use mathematical procedures out of their reac h. Plane Geometry started up his way through History by means of fundamental drawing tools: ruler and co mpass. Artisans used same tools to carry out their orna mental patterns but at some point they began to work manually using physical representations of fi gures or tiles previously drawing by means of ruler and compass. That is an important step for craftsman because this way provides tools that let him come in the world of symmetry opera tions and empirical knowledge of symmetry groups. Artisans started up to pr oduce little wooden, ceramic or clay tiles and began to experiment with them by means of joining pieces whether edge to edge or vertex to vertex in that way so it can c over the plane without gaps. Economy in making floor or ceramic tiles could be most important reason to develop these procedures. This empiric way to develop tilings led not only to discover all uniform tilings but later discovering of aperiodic tilings.

Determinación de las características acústicas de materiales de construcción de Ecuador - Ladrillo artesanal e industrial

En el presente trabajo se plantea el estudio de las características acústicas del ladrillo artesanal e industrial fabricado en Ecuador, considerando las características particulares respecto a la calidad de la materia prima, además del hecho de que a nivel artesanal su producción no está regularizada, si bien existen una serie de reglamentos no siempre son acatados por el productor artesanal, lo que hace que presente propiedades particulares. La idea principal de este trabajo es generar datos referenciales e iniciales, sobre las propiedades acústicas del ladrillo artesanal e industrial ya que en Ecuador, no existe ningún estudio de esta naturaleza sobre el tema. Además de crear los mecanismos necesarios para una posible ampliación del estudio a otros materiales propios de Ecuador que permitan generar una base de datos sobre sus propiedades acústicas. Otro aspecto importante sobre esta investigación es el familiarizarse con el uso de técnicas de medición, manejo de equipamiento y software diverso, del manejo y comparación de normativa. ABSTRACT. The purpose of this paper is the study of the acoustic characteristics of artisanal and industrial brick manufactured in Ecuador, considering the particular characteristics regarding the quality of raw materials, besides the fact that artisanal production level is unregulated, although there are a number of regulations are not always complied with by the artisan producer, which makes this particular properties. The main idea of this paper is to generate reference and baseline data on the acoustic properties of artisanal and industrial brick as in Ecuador, there is no study of this nature on the subject. In addition to creating the necessary mechanisms for a possible extension of the study to other materials from Ecuador that will generate a database on its acoustic properties. Another important aspect of this research is to get familiar with the use of measurement techniques, equipment and miscellaneous management software, management and comparison of legislation.

Artisan procedures to generate uniform tilings

This paper try to prove how artisans c ould discover all uniform tilings and very interesting others us ing artisanal combinatorial pro cedures without having to use mathematical procedures out of their reac h. Plane Geometry started up his way through History by means of fundamental drawing tools: ruler and co mpass. Artisans used same tools to carry out their orna mental patterns but at some point they began to work manually using physical representations of fi gures or tiles previously drawing by means of ruler and compass. That is an important step for craftsman because this way provides tools that let him come in the world of symmetry opera tions and empirical knowledge of symmetry groups. Artisans started up to pr oduce little wooden, ceramic or clay tiles and began to experiment with them by means of joining pieces whether edge to edge or vertex to vertex in that way so it can c over the plane without gaps. Economy in making floor or ceramic tiles could be most important reason to develop these procedures. This empiric way to develop tilings led not only to discover all uniform tilings but later discovering of aperiodic tilings.