Storage and preservation of blood and urine for trace element analysis. A review.

In any well-defined study, a sample preservation and storage scheme compatible with the information or analyte sought should be incorporated. This article emphasizes the need for preservation and storage of biological fluids collected for trace element determination; cites the major factors, such as container material, container pretreatment, storage time, storage temperature, and contamination of the laboratory environment affecting preservation; presents a historical account of the available literature studies on the preservation and storage of trace metals in whole blood, plasma, serum, and urine; and makes recommendations on the most effective storage and preservation methods.