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[Copper, zinc and aluminum contamination of blood specimens used for determination of these metals].

Increasing interest and demand in determinations of copper, zinc and aluminium in clinical biochemistry, led us to pay particular attention to problems of blood collection. We tested several blood collecting tubes for contamination by these metals. Evacuated tubes must be avoided; polystyrene and polypropylene tubes are apparently the least polluting. However, strict rules cannot be made, and each biochemist should test the blood collecting devices he wants to use for trace elements analysis.