G. Sundström

The synthesis and gas chromatographic properties of bromobiphenyls

Abstract Bromobiphenyls constitute a group of chemicals used extensively as flame retardants in textiles, etc., the environmental fate of which is not known. For a thorough insight into the chemistry, analysis and toxicological and biological effects access to pure bromobiphenyl isomers will be of great value. Literature on bromobiphenyl syntheses have therefore been compiled and, in addition, a number of new compounds have been prepared and characterised. The gas chromatographic behaviour of bromobiphenyls is also described.

The metabolism of 4,4′-dichlorobiphenyl in rats and frogs

Abstract The metabolism of 4,4′-dichlorobiphenyl in the rat has been investigated in detail and four monohydroxy-, four dihydroxy- and two trihydroxy metabolites were detected. The structures of the metabolites - except for the trihydroxy compounds - were ascertained by GC-MS studies and by comparison with synthetic compounds. Metabolism experiments in frog resulted in the isolation and characterisation of four metabolites. The structure of the major metabolites in both the rat and the frog are consistent with epoxidation of the biphenyl nucleus followed by epoxide ring opening accompanied by a 1,2-chlorine shift (NIH-shift). The formation of one minor rat metabolite, 4-chloro-3t-biphenylol can only be explained by reductive dechlorination.

Environmental chemistry of PCB-replacement compounds - III - the metabolism of 4-chloro-4′-isopropylbiphenyl and 2,5-dichloro-4′-isopropylbiphenyl in the rat

Abstract 4-Chloro-4′-isopropylbiphenyl and 2,5-dichloro-4′-isopropylbiphenyl, two model compounds for alkylated chlorobiphenyls (Chloralkylenes), are metabolized in the rat by two major routes. One pathway proceeds by stepwise oxidation of the isopropyl group to chlorobiphenyl carboxylic acid via intermediate keto- and carboxylic acid derivatives, and the other by hydroxylation of the chlorine substituted phenyl ring. A number of metabolites formed from either one or a combination of both pathways were identified by gas chromatography - mass spectrometry and synthesis.

THE METABOLISM OF p,p ′-DDT AND p,p ′-DDE IN THE PIG

ABSTRACT. The urinary metabolites of p,p′-DDT and p,p′-DDE in the pig have been investigated with emphasis on the detection of phenolic compounds. Upon dosing with p,p′-DDT, p,p′-DDA was found as the major metabolite. Hydroxylated p,p′-DDT or p,p′-DDA was not detected, but a minor amount of 3-hydroxy-p,p′-DDE was excreted. This phenol was also excreted by pigs given p,p′-DDE .