Review of Contamination Problems in Measuring Trace Elements (Revue Des Problemes de Contamination Dans Le Dosage Des Traces).


Book Description

Every sample analyzed must reflect the makeup of the environment in its natural state; contamination hazards, particularly in relation to trace measurements, range from the taking of the sample to the physical or chemical measurement of the content of the particular element being sought. The sources of contamination are many, sometimes built-in or accidental, but nevertheless frequently overlooked. The effects of this on trace measurements are analyzed one by one, and an effort is made to calculate the resulting error; insofar as possible, the best remedy for the situation is suggested. The following factors are studied: sampling, bagging, transport; physical treatment: parting, griding sifting; chemical treatment: acid or alkaline attack, solution; the influence of glassware, equipment, reagents, exposure to air, and handling by personnel. Ordinary practical examples are given to illustrate these sources of error. The main ways of measuring trace elements are reviewed, and the contamination hazards inherent in each are cited.







Sample Preparation for Trace Element Analysis


Book Description

Following the collection of a sample, every analytical chemist will agree that its subsequent preservation and processing are of paramount importance. The availability of high performance analytical instrumentation has not diminished this need for careful selection of appropriate pretreatment methodologies, intelligently designed to synergistically elicit optimum function from these powerful measurement tools. Sample Preparation for Trace Element Analysis is a modern, comprehensive treatise, providing an account of the state-of-the art on the subject matter. The book has been conceived and designed to satisfy the varied needs of the practicing analytical chemist. It is a multi-author work, reflecting the diverse expertise arising from its highly qualified contributors. The first five chapters deal with general issues related to the determination of trace metals in varied matrices, such as sampling, contamination control, reference materials, calibration and detection techniques. The second part of the book deals with extraction and sampling technologies (totaling 15 chapters), providing theoretical and practical hints for the users on how to perform specific extractions. Subsequent chapters overview seven major representative matrices and the sample preparation involved in their characterization. This portion of the book is heavily based on the preceding chapters dealing with extraction technologies. The last ten chapters are dedicated to sample preparation for trace element speciation. - First title to provide comprehensive sample preparation information, dealing specifically with the analysis of samples for trace elements. - The 39 chapters are authored by international leaders of their fields.




Trace Elements as Contaminants and Nutrients


Book Description

Access state-of-the-art research about trace element contamination and its impact on human health in Trace Elements as Contaminants and Nutrients: Consequences in Ecosystems and Human Health. In this ground-breaking guide, find exhaustive evidence of trace element contamination in the environment with topics like the functions and essentiality of trace metals, bioavailability and uptake biochemistry, membrane biochemistry and transport mechanisms, and enzymology. Find case studies that will reinforce the fundamentals of mineral nutrition in plants and animals and current information about fortified foods and nutrient deficiencies.




Trace Elements


Book Description

Over the last few years, we have witnessed increasing efforts dedicated to the scientific investigation and characteristics of trace elements. Especially in the field of human and animal nutrition, trace elements display a considerably attractive issue for research because they play an essential role in the nutrition of both animals and humans. Aquatic environments contaminated with trace elements are an emerging research area due to the toxicity, abundance, and environmental persistence of trace elements. Accumulation of heavy metals as a class of trace elements in various environments, and the subsequent transition of these elements into the food and feed chain, severely affects human health. The determination of type and concentration of trace elements is regarded as the first and most important step to follow the mechanisms controlling the dispersal and accumulation of trace elements. Element speciation in different media (water, soil, food, plants, coal, biological matter, food, and fodder) is pivotal to assess an element's toxicity, bioavailability, environmental mobility, and biogeochemical performance. Recently, new analytical techniques have been developed, which greatly simplified the quantitation of many trace elements and considerably extended their detection range. In this context, the development of reproducible and accurate techniques for trace element analysis in different media using spectroscopic instrumentation is continuously updated.




Trace Elements in Human and Animal Nutrition


Book Description

The major change in the format of the fifth edition is the presentation of the book in two volumes, necessitated by the rapidly increasing knowledge of metabolism, interactions, and requirements of trace elements ... The guiding principle was to present the minimum of results that would serve as a logical foundation for the description of the present state of knowledge. Recent results of research were accommodated by devoting new chapters to the subjects "Methodology of Trace Element Research" and "Quality Assurance for Trace Element Analysis" and by expanding the discussion of lithium and aluminum in separate, new chapters. The first two subjects are of outstanding importance as determinants of future progress. The concern for the quality of analytical data motivated the authors of the individual chapters to review critically and, where necessary, revise analytical data presented in the previous editions. The rapid progress of trace analytical methodology since the mid-1970s has changed what had been accepted as normal for the concentrations of many trace elements in tissues and foods. The new data reflect the present state of the art in trace element analysis, but they may be subject to future revision.




Trace Element Analysis in Biological Specimens


Book Description

The major theme of this book is analytical approaches to trace metal and speciation analysis in biological specimens. The emphasis is on the reliable determination of a number of toxicologically and environmentally important metals. It is essentially a handbook based on the practical experience of each individual author. The scope ranges from sampling and sample preparation to the application of various modern and well-documented methods, including quality assessment and control and statistical treatment of data. Practical advice on avoiding sample contamination is included. In the first part, the reader is offered an introduction into the basic principles and methods, starting with sampling, sample storage and sample treatment, with the emphasis on sample decomposition. This is followed by a description of the potential of atomic absorption spectrometry, atomic emission spectrometry, voltammetry, neutron activation analysis, isotope dilution analysis, and the possibilities for metal speciation in biological specimens. Quality control and all approaches to achieve reliable data are treated in chapters about interlaboratory and intralaboratory surveys and reference methods, reference materials and statistics and data evaluation. The chapters of the second part provide detailed information on the analysis of thirteen trace metals in the most important biological specimens. The following metals are treated in great detail: Aluminium, arsenic, cadmium, chromium, copper, lead, selenium, manganese, nickel, mercury, thallium, vanadium and zinc. The book will serve as a valuable aid for practical analysis in biomedical laboratories and for researchers involved with trace metal and species analysis in clinical, biochemical and environmental research.







Quantitative Trace Analysis of Biological Materials


Book Description

The understanding of the functions of trace elements in metabolism, whether associated with microorganisms, plants or animals, has advanced considerably during the last twenty years. There are two main aspects of the importance of trace elements in biological materials: first, their toxic effects and secondly, the essential nature of some of the elements for normal growth and health. Research in trace elements and their essential role in biological processes has advanced through several stages, necessitating more and more effective methods of determination. Despite the marked improvements in methods of trace analysis during these twenty years, the ever increasing need for higher sensitivity to meet new demands has meant the greater need, not only for improving the limits of detection, but also for new standard reference materials, better sampling, better sample handling and better design of trace and ultra-trace analysis laboratories. This book focusses on all areas of trace element determination with detailed discussion on all major methods of analysis. Additionally, the determination of concentrations of major toxic and essential trace elements is discussed at length.




Trace Elements


Book Description