Abstract: Relates to a method for pathogen reduction of a blood product comprising: i) removing oxygen from a blood product; ii) reducing blood pathogens from said blood product t: adding amustaline (S-303) to a final concentration of 0.2 millimolar (mM); and glutathione (GSH) to a concentration of 20 mM; iii) reducing S-303 to a concentration of less than 1 nmol/L comprising incubating said oxygen reduced blood product under oxygen reduced conditions for up to 6 hours; and further relates to a pathogen reduced, oxygen reduced blood product having an oxygen saturation (sO2) of less than 25%, a pCO2 of 90 mmHg or less at 37° C., and having a amustaline (S-303) concentration of less than 1 nmol/L.