The long term goal of the research proposal is to elucidate the mechanism(s) of translational control as effected by chemical environmental contaminants which may interfere with normal hematopoietic functions (e.g., benzene, gold and other heavy metals). Our specific objectives for this two-year project will be to: (1) Study the effect of benzene of the specific phosphorylation of eIF-2Alpha in rabbit reticulocytes, (2) Purify the benzene-activated translational inhibitor(s) from rabbit reticulocytes, (3) Study the mode of action of the purified benzene-activated translational inhibitor(s). Methods to be used for this study will include (1) protein synthesis assays, (2) analysis of eIF-2Alpha phosphorylation by two dimensional SDS gel electrophoresis, and (3) purification of benzene-activated translational inhibitor(s) by column chromatography.