Lipid peroxidation, an autocatalytic free radical process, is increased in a wide variety of conditions including various hemolytic anemias and hemoglobin disorders. Increased erythrocyte lipid peroxidation occurs in the presence of iron species and some heme moieties. In this study, greatly reduced concentrations of malondialdehyde (MDA), an indicator of lipid peroxidation, were observed in stored blood anticoagulated with citrate, phosphate, dextrose, and adenine (CPDA-1) upon the addition of deferoxamine mesylate (DM), diethylenetriaminepentaacetic acid (DTPA), and ethylenediaminetetraacetic acid (EDTA) (P less than 0.001). Human transferrin has essentially no effect on lipid peroxidation. Conversely, penicillamine and butylated hydroxytoluene significantly increased lipoperoxide production. Although bathophenanthroline disulfonic acid (BPD) appeared to be very effective in reducing lipid peroxidation, its complex chromatographic patterns which were due to the presence of multiple thiobarbituric acid reactive substances, were difficult to fully evaluate. The addition of appropriate metal chelators to stored blood may be effective in increasing the viability and longevity of transfused red cells.