The objectives of the proposed research are to investigate the GSH-dependent substitution vs. reduction of benzyl halides, to study the dehydrohalogenation of polyhalogenated alkanes, to study the microsomal reduction of polyhalogenated alkanes, to study the GSH-dependent dehalogenation of vic-dihalides, to study the mechanisms by which 1,2-dichloroethane and 1,2-dibromoethane produce hepatic and renal toxicity, to study the enzymes involved in the reductive dehalogenation of alpha-haloketones and to study enzyme catalyzed nucleophilic substitution reactions of halogenated olefins and to determine the relationship of this reaction to the production of nephrotoxicity.