Despite the development of innovative new analytical techniques for biological trace element research, today's trace element investigators face formidable obstacles to obtaining reliable data. This complete reference identifies and assesses the challenges the analyst encounters at each stage of an analysis, and discusses the effects of various techniques on the sample.Three internationally recognized scientists and authors consider the effects of the numerous collection, storage, and sample preparatory techniques used in sample analysis. Proper analytical quality control, including such critical factors as sampling and sample preparation, specimen preservation and storage, and ashing, is examined. The book also looks at sample preparation methods unique to various instruments and speciation chemistry issues, and examines the link between chemical analysis and specimen banking. A previously unrecognized source of error, presampling factors, is also discussed.