Studies in the Sulphur Metabolism of the Dog. II. The Constancy of the Relative Output of Ethereal Sulphate and of Neutral Sulphur after the Oral Administration of the Halogen Substituted Benzenes

BAUMANN and PREUSSE [1879] were the first to point out that bromobenzene was partly excreted by the dog as p-bromophenylmercapturic acid and partly as p-bromophenyl sulphate. It is known that p-bromophenol gives rise to p-bromophenyl sulphate, but as yet no mercapturic acid has been isolated from the urine of dogs taking this substance. It is largely a question of dosage. The phenol coefficient (B. coli) for p-bromophenol is 7-4 [Cooper and Woodhouse, 1923] .and its toxicity to mice is about the same as that of phenol [Bechold and Ehrlich, 1906]. On the other hand bromobenzene can be ad- ministered safely to animals in comparatively large doses. To prepare mer- capturic acids therefore the benzenes and not the phenols have always been administered to dogs. Observers generally do not make a distinction between the metabolism of bromobenzene and that of p-bromophenol. They assume that bromobenzene is first oxidised to p-bromophenol before it is converted to mercapturic acid. This is almost certainly true but the proof is incomplete.