The effective temperature of atomic vapor in a graphite furnace was studied in order to minimize chemical interference during the determination of trace elements in whole blood. The effective temperature of atomic vapor, which corresponds to the sample temperature, was raised to about 500°C by using a rapid heating method combined with platform techniques and a Pd matrix modifier. As a result, this technique has been found to be effective in minimizing interference in whole blood analysis without any sample pretreatment. On the other hand, the residue of a whole blood sample and the Pd modifier remaining after asking was something like porous carbon or sintered metal. This finding strongly supports the superiority of the peak-area method over others used in this assay format. Simultaneous direct determinations of Cr, Ni, Mn, and Pb in whole blood can be carried out by applying a combination of rapid heating, platform and Pd matrix modifier techniques.