Download or read book Speciation and Reactivity of Toxic Metals in Anoxic Sediments written by and published by . This book was released on 1996 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this research was to determine the influences of metal speciation on the kinetics of toxic metal solid phase transitions and interactions between solid phases and natural waters. Primary emphasis was on sulfidization-desulfidization reactions associated with near interfacial anoxic sediments. The approach utilized both the collection and analysis of natural samples and laboratory experiments. Samples from Chesapeake Bay were studied from organic matter rich and poor sites on a time-dependent basis in collaboration with the ONR-sponsored research of Drs. Donat and Burdige. A time-dependent field study was also conducted in Offatts Bayou, Texas, which is particularly well suited to our objectives because of the major redox changes that occur on a seasonal basis to the deeper basin waters. Sediments in these areas are more spatially heterogeneous in composition than anticipated and can also undergo seasonal variations in their trace metal chemistry. These results, coupled with those of the laboratory experiments, demonstrated the very dynamic nature of toxic metal speciation in sediments during early diagenesis. They point to the need to use considerable caution in the application of limited data bases and simple time-independent models for predictihg potential bioavailability of toxic metals.
Download or read book Speciation of Metals in Water Sediment and Soil Systems written by Lars Landner and published by Springer. This book was released on 2006-04-10 with total page 229 pages. Available in PDF, EPUB and Kindle. Book excerpt: The particular behavior of trace metals in the environment is determined by their specific physico-chemical form rather than by their total concentration. The introduction of atomic absorption spectrometry has lead to a plethora of scientific papers and reports in which metal concentrations in the environment are only reported as total concentrations. Only recently has the need for improved knowledge on the various forms and bioavailability of metals been realised. Considerable research effort is now devoted to measuring the concentrations of trace metals in surface waters. Efforts are made to couple chemical analytical techniques to process-related biological problems. The proceedings of the workshop on The Speciation of Metals in Water, Sediment and Soil Systems held in Sunne, Sweden, comprise these efforts and show aspects for further cooperation between analytical chemists and biologists.
Download or read book Metals in Society and in the Environment written by Lars Landner and published by Springer Science & Business Media. This book was released on 2006-01-15 with total page 422 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents new results on metal fluxes from society to the environment, on metal speciation in water, soil and sediment, and its mobility, biological uptake and toxicity. New approaches, like the Acid Volatile Sulphide (AVS) concept to predict metal bioavailability in sediments, and the Biotic Ligand Model to calculate the toxicity of metals to aquatic organisms, are critically evaluated, with a focus on copper, nickel, zinc, and, chromium.
Download or read book Chemical Speciation and Heavy Metal Mobility in Contaminated Marine Sediments written by Alexandra Katsiri and published by . This book was released on 2009 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt: Management of sediments from coastal areas, contaminated with heavy metals and organic substances, is a very critical issue. Management decisions are usually based on total pollutant concentrations and various guidelines that are used by different countries. Heavy metals can be mobilized from polluted sediments if they are exposed to changing environmental conditions that occur during excavation, disposal at sea, or disposal in confined facilities. This paper examines the changes in heavy metals partitioning to binding phases in contaminated marine sediments and the release of metals to the environment. Environmental conditions are simulated by submitting sediments to a modified elutriation test with oxygenated and deoxygenated seawater. A sequential extraction procedure is used to determine the binding fractions of heavy metals in the sediments. Fractionation analysis of excavated marine sediments from the port of Piraeus, Greece showed that copper is primarily associated with organic matter, whereas lead and zinc are primarily associated with iron oxides. Under anoxic conditions, the metals bound to the various binding fractions remain practically stable. On the other hand, under oxic conditions, an increase in the concentration of metals associated with carbonates and a decrease in the concentration of metals associated with organic matter and iron oxides were observed. Both under oxic and anoxic conditions, actual metal mobility was very low and less than 0.5 % of total metal mass was found in the dissolved phase.
Download or read book Metal Contaminated Aquatic Sediments written by HerbertE. Allen and published by Routledge. This book was released on 2018-04-27 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past decade the sediments of many rivers, lakes, and estuaries have been contaminated by inorganic and organic materials. Contaminants from sediments, under certain conditions, can be released into overlying waters. Thus, sediments may be an important source of contaminants to waters in which littoral and atmospheric contaminants have been reduced or eliminated. Often found in aquatic sediments, metals are exposed to many reactions, such as sorption and precipitation, and are greatly influenced by the redox conditions in the sediment. The reactions - usually over a period of time - reflect biotic processing as well as chemical transformations. This book describes these important processes. Metal Contaminated Aquatic Sediments outlines advances in environmental chemistry, effective new modeling techniques, applications for biological treatment, and cycling and transport of trace metals in sedimentary environments. Each chapter contains a detailed reference section that draws upon a stunning array of sources. The book includes many figures and tables that illustrate the process under discussion. Features
Download or read book Sediments written by Renato Baudo and published by CRC Press. This book was released on 1990-08-27 with total page 432 pages. Available in PDF, EPUB and Kindle. Book excerpt: This important volume-the product of a meeting of a select group of scientists-provides the most recent research results from the world's leaders in the study of toxic pollutants in sediments. It gives practical information on measuring and mapping distributions of concentrations of pollutants and their toxic effects in sediments. Also covered are the use and relative advantages and disadvantages of benthic chambers, sedimentation traps, box corers, "peepers" and other sampling techniques in sediment research and assessment. Important topics covered include: bioassay, elemental speciation, diffuse source problems, nutrient flux, biomethylation, bioavailability, and toxicity assessment. Will help in assessment and monitoring of chemistry, dynamics, bioavailability, and toxicity of pollutants, as well helping to chart courses for remedial action. This book will be of interest to anyone interested in the processes controlling the chemistry and movement of pollutants in sediments, especially: limnologists aquatic toxicologists engineers lake managers ecologists biologists environmental chemists
Download or read book Metal Speciation and Bioavailability in Aquatic Systems written by André Tessier and published by John Wiley & Sons. This book was released on 1995 with total page 704 pages. Available in PDF, EPUB and Kindle. Book excerpt: This publication deals with fundamental concepts and models, speciation measurements and field applications in metal speciation and bioavailability in aquatic environments. This volume provides a thorough review of current developments concerning the interactions between trace metals and aquatic organisms.
Download or read book Sediments and Toxic Substances written by Wolfgang Calmano and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 337 pages. Available in PDF, EPUB and Kindle. Book excerpt: In modern sediment research on contaminants five aspects are discussed which, in an overlapping succession, also reflect develop ment of knowledge on particle-associated pollutants during the past twenty-five years: (1) identification of sources and their distribution; (2) evaluation of solid/solution relations; (3) study of transfer mecha nisms to biological systems; (4) assessment of environment impact; and (5) selection and further development of remedial measures, in par ticular, of dredged materials. Scientific research and practical develop ment are still expanding in all these individual aspects. Similar to other waste materials, management of contaminated sed iments requires a holistic approach. This means that assessment of biogeochemical reactions, interfacial processes and transfer mecha nisms as well as the prognosis of long-term borderline conditions, in particular of capacity-controlling properties, should be an integrated part of the wider management scheme, i.e., the analytical and experi mental parameters should always be related to potential remediation options for a specific sediment problem. The underlying coordinated project, which was funded by the German Federal Ministry for Science and Technology (now the Federal Ministry for Education, Science, Research and Technology) provided excellent opportunities for multidisciplinary effort, bringing together biologists, chemists, engineers, geologists and other researchers. During its active phase, the group attracted much interest nationally and internationally. The group members highly appreciate the manifold contacts and invitations during the past five years.
Download or read book Physico chemical Speciation and Chemical Transformations of Toxic Metals in the Environment written by R. M. Harrison and published by . This book was released on 1990 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: Review article describes common experimental techniques for speciation of trace metals like copper in environmental media. Notes that the Tessier method of sequential extractions is the most commonly utilized scheme for evaluating the bioavailability of metals in soils and sediments.
Download or read book Biological Chemical Oceanography Program Abstract Book written by and published by . This book was released on 1995 with total page 512 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Processes Affecting the Distribution and Speciation of Heavy Metals in the Rhine Meuse Estuary written by Marcel Paalman and published by Facultiet Aardwetenschappen Universiteit Utracht. This book was released on 1997 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Environmental Risk Assessment of Soil Contamination written by Maria C. Hernandez Soriano and published by BoD – Books on Demand. This book was released on 2014-03-26 with total page 922 pages. Available in PDF, EPUB and Kindle. Book excerpt: Soil is an irreplaceable resource that sustains life on the planet, challenged by food and energy demands of an increasing population. Therefore, soil contamination constitutes a critical issue to be addressed if we are to secure the life quality of present and future generations. Integrated efforts from researchers and policy makers are required to develop sound risk assessment procedures, remediation strategies and sustainable soil management policies. Environmental Risk Assessment of Soil Contamination provides a wide depiction of current research in soil contamination and risk assessment, encompassing reviews and case studies on soil pollution by heavy metals and organic pollutants. The book introduces several innovative approaches for soil remediation and risk assessment, including advances in phytoremediation and implementation of metabolomics in soil sciences.
Download or read book Geochemical Fractionation Speciation and Bioavailability of Heavy Metals in Stream Sediments in Aurora MO written by Miles A. Avery Pearson and published by . This book was released on 2017 with total page 128 pages. Available in PDF, EPUB and Kindle. Book excerpt: Stream sediments from Chat Creek in Aurora, MO, part of the former Tristate Mining District, were digested via a sequential extraction procedure modeled after the Tessier method. Prior sampling had shown elevated levels of zinc, lead, and cadmium in sediments located near former chat piles. Metals in sediments were divided into four geochemical fractions: 1) easily exchangeable, 2) carbonate-bound, 3) iron-manganese oxides-bound, and 4) organic matter-bound. The distribution of the metals within these fractions can help predict the bioavailability and speciation of said metals. The majority of metals were contained in the third and to a lesser extent the fourth fraction. In these four fractions, 73.5 percent of zinc, 54.0 percent of lead, and 73.4 percent of cadmium was recovered from total metals present in sediment samples relative to preliminary total metal analysis. Metals in plant samples also showed significant contamination and suggested bioavailability of metals. Water samples were also analyzed, but showed no significant metal contamination.
Download or read book Metal Speciation Mixtures and Environmental Health Impacts written by Eun Joo Park and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Numerous applications of heavy metal have caused to their wide contamination in the environmental system and raised serious concerns over potential harmful effects on public health and the environment. Water, sediment, and dietary food are the main exposure media of heavy metal pollution and key determinants of adverse human and environmental health effects. Heavy metal(s) toxicity and speciation involve various mechanistic features with specific media and some of them are not clearly investigated. In particular, biological effects such as toxicity are not related to the total concentration of heavy metals in media, and many laboratory and field studies have supported this supposition. Organisms respond to the bioaccessible and bioavailable fraction of metals only, not the total concentration. The bioaccessibility and bioavailability of toxicants are dependent on chemical properties of the contaminant, the many exposure pathways, and temporal variability of these variables with respect to uptake by the target organism. Usually, bioavailable fractions are estimated using chemical or biological approaches. For this study, biological approaches were performed to better ascertain the toxic effects of heavy metals on organisms. A better understanding of bioaccessibility and bioavailability can be a useful tool in exposure and risk assessment. Therefore, this study presents experimental designs focusing on assessing of the bioaccessibility and bioavailability of metals in aquatic, benthic organisms and dietary food. This study also examines the role of metal mixtures on the adverse effects of metals.
Download or read book Speciation and Biovailability of Heavy Metals Sulphur Phosphorus and Cyanide in Soils and Sediments written by H. Rogaar and published by . This book was released on 1997 with total page 215 pages. Available in PDF, EPUB and Kindle. Book excerpt: The dynamic balance between chemical binding and biological adsorption; The chemical behaviour of cynamide in contaminated soils; Speciation influenced by multicomponent adsorption and complexation - analysis of heterogeneous systems with variable surface charge and surface potential research; Speciation of heavy metal ions as influenced by interactions of montomorillonite, Al hydroxide polymers and citrate; Laboratory simulation and field study concerning soil processes with respect to mobility and plant availability of heavy metals: dynamics, speciation and the role of organic matter; Effect of land use changes on metal solubility and speciation in soils; Bioavailability research; Lake and river sediment research.
Download or read book Chemical Speciation in the Environment written by A. M. Ure and published by John Wiley & Sons. This book was released on 2008-04-15 with total page 472 pages. Available in PDF, EPUB and Kindle. Book excerpt: Considerable recent research has focused on the topic of chemical speciation in the environment. It is increasingly realised that the distribution, mobility and biological availability of chemical elements depend not simply on their concentrations but, critically, on the forms in which they occur in natural systems. Continuing developments in analytical chemistry have made speciation practicable even where analytes are present at trace levels (as is often the case in natural samples). In the second edition of this book, the expertise of scientists involved in chemical speciation in various fields have been brought together to provide an overview of the current status of speciation science and indicate how the field may develop in the future.
Download or read book Encyclopedia of Aquatic Ecotoxicology written by Jean-Francois Férard and published by Springer. This book was released on 2013-06-14 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: With its 104 chapters, this Encyclopedia of aquatic ecotoxicology reveals the diversity of issues, problems and challenges that have faced, and are facing today, receiving environments. It also indicates ways by which tools, strategies and future investigations can contribute to correct, minimize, solve and prevent water quality degradation. Structured homogeneously, the chapters convey salient information on historical background, features, characteristics, uses and/or applications of treated topics, often complemented by illustrations and case studies, as well as by conclusions and prospects. This work is most suitable for teaching purposes. Academics, for example, could literally deliver comprehensive lectures to students simply based on chapter outlines and contents. Meet the Authors of the Encyclopedia! Check out 'Meet the Authors' under ADDITIONAL INFORMATION (Right menu).
