Contribution of 3,4-Dichlorophenylhydroxylamine in Propanil-Induced Hemolytic Anemia

Abstract

The methemoglobinemia and hemolytic anemia observed in experimental animals given aniline has been shown to be mediated by its N-oxidation metabolite, phenylhydroxylamine (Harrison, J.H. et al., 1987; Harrison, J.H. et al., 1986). The aniline derivative, propanil (3,4-dichloropropionanilide), is a widely used arylamide herbicide that has been shown to induce methemoglobinemia in experimental animals following conversion of the parent amide to one or more oxidized metabolites (Singleton, S > D. et al., 1973; Chow, A.Y.K. et al., 1975). Two methemoglobinemic metabolites of propanil have been identified, 3,4-dichlorophenylhydroxylamine (N-hydroxy-3,4-dichloroaniline) and 6-hydroxy-3,4-dichloroaniline (McMillan, D.C. et al., 1990). In view of the hemolytic activity of phenylhydroxylamine, we have examined the hemolytic potential of propanil and its metabolites in rats.