Studies in detoxication. 42. Fluorobenzene. Spectrophotometric determination of the elimination of unchanged halogenobenzenes by rabbits. A comparison of the oxidation in vivo of fluorobenzene and of benzene

Abstract

A study was made of the elimination in the expired air of unchanged fluoro-, chloro-, bromo- and iodo-benzene after oral admn. to rabbits. A spectrophotometric method for the detn. of these halogenobenzenes in expired air was described. The u.-v. absorption spectra in ethanol were recorded and discussed. Of doses of 0.5 and 1 g. of fluorobenzene/kg., 44 and 64% respectively are eliminated unchanged in the expired air. At a dose level of 0.5 g./kg. 27% of chloro-, 6% of bromo- and 3% of iodo-benzene were excreted unchanged in the expired air. These results are discussed. The elimination of fluorobenzene in the urine as ethereal sulfates, glucuronides and mercapturic acid was studied quantitatively and the results suggest that it behaves metabolically like benzene rather than the other halogenobenzenes. Whereas chloro-, bromo-and iodo-benzenes yield large amts. (about 25%) of mercapturic acid in the urine, benzene and fluorobenzene yield only small amts. (about 1-2%). Fluorobenzene in single doses up to 1 g./kg. is not highly toxic to rabbits.