Discusses the biochemical and geological cycling of selenium (Se), its worldwide distribution, and the factors controlling its fate and transport within and between major environmental media, presenting a global assessment of selenium's complex environmental behaviour. The focus of this work is upon Se management and remediation strategies.

The Role of Selenium in Nutrition reviews the most pertinent scientific literature dealing with the basic aspects of the present understanding of the roles of selenium (Se) in nutrition and health. The book begins with a general discussion of Se, covering its various forms, chemistry and physical properties, and techniques for Se analysis. This is followed by separate chapters on the environmental aspects of Se, including its presence in mineral deposits, soils, water, air, and uptake by plants; Se contents of human foods and animal feedstuffs; biological utilization of dietary Se; and absorption, excretion, metabolism, and tissue concentrations of Se. Subsequent chapters deal with the biochemical functions of Se; Se-related diseases of animals and livestock; the role of Se in human health and in support of normal immune function and disease resistance; and the relationship of Se and cancer. The final chapter reviews the evidence concerning the toxicity of Se compounds and sets this in perspective with current knowledge of the roles of Se in nutrition and health, and of the normal exposures of animals and humans to Se compounds.

This book covers many facets of plant selenium (Se) accumulation: molecular genetics, biochemistry, physiology, and ecological and evolutionary aspects. Broader impacts and applications of plant Se accumulation also receive attention. Plant Se accumulation is very relevant for environmental and human health. Selenium is both essential at low levels and toxic at high levels, and both Se deficiency and toxicity are problems worldwide. Selenium can positively affect crop productivity and nutritional value. Plants may also be used to clean up excess environmental Se. Selenium in plants has profound ecological impact, and likely contributes to Se movement in ecosystems and global Se cycling.

Selenium is arguably the naturally occurring trace element of greatest concern worldwide. In excessive amounts it can lead to toxicosis and teratogenesis in animals, while the impact of selenium deficiency can be even more significant. Contributors from 22 countries explored the connections and inter-relationships between selenium in the environmen

Selenium plays a fascinating and still poorly understood role in the function of living cells and therefore in human health. Starting with investigations over 60 years ago into its role as a toxic agent in livestock disease, selenium studies have progressed rapidly with the application of tools from immunology and molecular biology. Selenium is now known to be important in human and animal nutrition, has been discovered as a structural component of so-called selenoproteins, and may play a number of physiological roles, ranging from cancer protection to hormone metabolism. Selenium in Biology and Human Health presents research syntheses on a range of topics involving selenium, written by specialists from around the world. It will be of interest to cell biologists and physiologists, nutritional scientists, and animal health researchers.

As discussed in this book, a large body of evidence indicates that selenium is a cancer chemopreventive agent. Further evidence points to a role of this element in reducing viral expression, in preventing heart disease, and other cardiovascular and muscle disorders, and in delaying the progression of AIDS in HIV infected patients. Selenium may also have a role in mammalian development, in male fertility, in immune function and in slowing the aging process. The mechanism by which selenium exerts its beneficial effects on health may be through selenium-containing proteins. Selenium is incorporated into protein as the amino acid selenocysteine. Selenocysteine utilizes a specific tRNA, a specific elongation factor, a specific set of signals, and the codeword, UGA, for its cotranslational insertion into protein. It is indeed the 21st naturally occurring amino acid to be incorporated into protein and marks the first and only expansion of the genetic code since the code was deciphered in the mid 1960s.