An Overview of Arsenic Metabolism and Toxicity

Zuzana Drobna1, Miroslav Styblo2, David J. Thomas3

1 Department of Nutrition, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 2 Center for Environmental Medicine, Asthma, and Lung Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 3 Pharmacokinetics Branch, Experimental Toxicology Division, National Health and Environmental Effects Research Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina
Publication Name:  Current Protocols in Toxicology
Unit Number:  Unit 4.31
DOI:  10.1002/0471140856.tx0431s42
Online Posting Date:  November, 2009
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It is likely that at least some of the toxic and carcinogenic effects associated with exposure to inorganic arsenic are, in fact, due to actions of its methylated metabolites. Here, we provide an overview of current models for the biological methylation of arsenicals. This information provides a context for understanding the chemical, biochemical, and genetic approaches to elucidation of the formation and function of methylated arsenicals, which are presented in the following units in this chapter. Curr. Protoc. Toxicol. 42:4.31.1‐4.31.6. © 2009 by John Wiley & Sons, Inc.

Keywords: inorganic arsenic; methylated arsenic metabolites; As; methyltransferase

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Table of Contents

  • Introduction
  • Nomenclature
  • General Aspects of Arsenic Methylation
  • Linkage of Arsenic Methylation and Toxicity
  • Enzymatic Basis of Arsenic Methylation in the Context of Cellular Metabolism
  • Identifying the Products of Arsenic Metabolism
  • Disclaimer
  • Literature Cited
  • Figures
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Literature Cited

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