49,148 research outputs found
An Ethnography of Entanglements: Mercuryâs Presence and Absence in Artisanal and Small-scale Gold-mining in Antioquia, Colombia
This paper describes a âfollow the thingâ methodology as applied to an ethnography of entanglements. This methodology allowed for a materially and politically nuanced understanding of Antioquia, Colombiaâs response to mercury pollution. This pollution primarily originates from the Artisanal and Small-Scale Gold Mining (ASGM) industry where mercury is employed in the gold extraction process. In following the mercury, the authors experiment with an ethnography of entanglements. The paper discusses how they address the current lacunae in mining ethnographies by focussing on mining as âpracticeâ, going past the provision of technical descriptions of mining and ethnographic descriptions of miners to an ethnography of mining. This ethnographic approach considers the politics of materiality and addresses a lack of attention to the impacts of the presence and absence of materials on social life. Various mining practices in Antioquia illuminate how entanglements between miners and mercury have been co-constitutive of particular modes of ASGM. The paper will also provide examples of ânegative mercury entanglementsâ where efforts have been made to extricate mercury from mining practices. Rather than creating a vacuum, these mercury absences have been generative of new contested symbolic and material arrangements including entrepreneurial and âresponsibleâ mining, debates over minersâ rights, and the creation of new political relationships between ASGM and large-scale mining companies.fals
Determination of Arsenic, Mercury and Barium in herbarium mount paper using dynamic ultrasound-assisted extraction prior to atomic fluorescence and absorption spectrometry
A dynamic ultrasound-assisted extraction method using Atomic Absorption and Atomic Flourescence spectrometers as detectors was developed to analyse mercury, arsenic and barium from herbarium mount paper originating from the herbarium collection of the National Museum of Wales. The variables influencing extraction were optimised by a multivariate approach. The optimal conditions were found to be 1% HNO3 extractant solution used at a flow rate of 1 mL min-1. The duty cycle and amplitude of the ultrasonic probe was found to be 50% in both cases with an ultrasound power of 400 W. The optimal distance between the probe and the top face of the extraction chamber was found to be 0 cm. Under these conditions the time required for complete extraction of the three analytes was 25 min. Cold vapour and hydride generation coupled to atomic fluorescence spectrometry was utilized to determine mercury and arsenic, respectively. The chemical and instrumental conditions were optimized to provide detection limits of 0.01ng g-1 and 1.25 ng g-1 for mercury and arsenic, respectively. Barium was determined by graphite-furnace atomic absorption spectrometry, with a detection limit of 25 ng g-1. By using 0.5 g of sample, the concentrations of the target analytes varied for the different types of paper and ranged between 0.4â2.55 ”g g-1 for Ba, 0.035â10.47 ”g g-1 for As and 0.0046â2.37 ”g g-1 for Hg
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Leveraging Epidemiology to Improve Risk Assessment.
The field of environmental public health is at an important crossroad. Our current biomonitoring efforts document widespread exposure to a host of chemicals for which toxicity information is lacking. At the same time, advances in the fields of genomics, proteomics, metabolomics, genetics and epigenetics are yielding volumes of data at a rapid pace. Our ability to detect chemicals in biological and environmental media has far outpaced our ability to interpret their health relevance, and as a result, the environmental risk paradigm, in its current state, is antiquated and ill-equipped to make the best use of these new data. In light of new scientific developments and the pressing need to characterize the public health burdens of chemicals, it is imperative to reinvigorate the use of environmental epidemiology in chemical risk assessment. Two case studies of chemical assessments from the Environmental Protection Agency Integrated Risk Information System database are presented to illustrate opportunities where epidemiologic data could have been used in place of experimental animal data in dose-response assessment, or where different approaches, techniques, or studies could have been employed to better utilize existing epidemiologic evidence. Based on the case studies and what can be learned from recent scientific advances and improved approaches to utilizing human data for dose-response estimation, recommendations are provided for the disciplines of epidemiology and risk assessment for enhancing the role of epidemiologic data in hazard identification and dose-response assessment
Leaching behaviour of mercury from hazardous solid waste generated by chlor-alkali industry
Through the conventional chlor-alkali production process, highly mercury (Hg) contaminated waste sludge is produced. Improper handling and disposal of this sludge may cause an environmental hazard. The leaching behaviour of Hg of land disposed mercurial sludge, originating from a chlor-alkali plant that still is in operation, was investigated using the German DIN 38414-S4 test. The total mercury content of the samples was above 1500 mg/kg, allowing the material to be classified as hazardous and high mercury waste. Concentrations of Hg in the leachates were higher than 0.02 mg/l stipulated by the 1991 EEC Landfill Directive Draft as a maximum limit for a waste that is to be landfilled. Total Hg contents and leachability differed markedly between the samples, pointing to a heterogeneity in the production of the sludge. The more limited release of Hg from one of the samples might reflect an ageing effect, or might reflect a better quality of the stabilization process at the time of production. Results indicate that the approach used to stabilize the sludge has not been sufficiently effective, and warrant caution about existing disposal sites and future management of these mercury containing waste materials
Mercury Pollution Due to Small-Scale Gold Mining in the Philippines: An Economic Analysis
The study reviews small-scale gold mining in the Philippines and assesses economically mercury pollution and other development problems of the industry. The end purpose is to suggest measures to address the problems and promote better environmental and overall management of small-scale mining. The study uses secondary data from mining institutions as well as primary data from key informants and small-scale gold miners and processors in the two case study sites.natural resources and environment, environmental issues, environmental management
Waste Reduction, Construction and Demolition Debris: Guide for Building, Construction and Environmental Professionals, Revised November 2008
This document is intended to lay the foundation for resource reduction strategies in new construction, renovation and demolition. If you have an innovative idea or information that you believe should be included in future updates of this manual please email Shelly
Codner at [email protected] or Jan Loyson at [email protected].
Throughout this manual, we use the term âwaste reductionâ to define waste management initiatives that will result in less waste going to the landfill. In accordance with the waste management hierarchy these practices include reducing (waste prevention), reusing
(deconstruction and salvage), recycling and renewing (making old things new again) - in that order. This manual will explain what these practices are and how to incorporate them into your projects
Arsenic Exposure to Fish and Shellfish Consumption Among Community in Makassar, Indonesia
Fish and shellfish contaminated by Arsenic (As) heavy metals from people activity discharge into the coast. Coastal community was exposure risk by As due to consumption of marine products. This study aimed to determine of human health risks level who consume fish and shellfish that contain As in Kaluku Bodoa and Untia coastal, Makassar. This research designed by observational and Environmental Health Risk Analysis (EHRA) approach. Human sample were 49 people and 8 environmental samples that selected based on certain criteria. Data collected through environmental assestment, interview and anthropometric data measurement. Data analyzed with EHRA methods. The results showed that the highest mean As levels found in Leiognatus equulus fish i.e. 1.589 mg/kg and Gafrarium tumidum shellfish i.e. 4.244 mg/kg of Untia coastal. The mean level of the carcinogenic risk for fish and shellfish consumption were unacceptable because they contain As that demonstrated value of more than exponent 4 (ECR > E-4) and non-carcinogenic risk mean level was value of more than 1 (RQ > 1). Fish and shellfish consumption considered unsafe and will impact health problems for the community. Community should be restrict the frequency and amount of fish and shellfish consumption
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