Design and use of quality control samples in a collaborative study of trace metals in daily diets

Summary A series of six simulated diets consisting of mixtures of a limited number of foodstuffs have been produced, primarily to be used as external quality control samples in the ongoing WHO/UNEP HEAL-project. Lead and cadmium in the simulated diets have been determined by several reference laboratories. Zinc, copper, iron, manganese, chromium, nickel, calcium, aluminium, cobalt and arsenic have so far been analysed by at least two different laboratories. Examples of reference values and of the practical use of the diets in analytical quality assurance are given.

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Planung und Verwendung von Qualitätskontrollproben bei einem Ringversuch für Spurenmetalle in der täglichen Nahrung