Studies in detoxication. 63. The metabolism of halogenobenzenes; (a) meta-dichlorobenzene (b) further observations on the metabolism of chlorobenzene.

2. o-Dichlorobenzene also gives rise to 3:4dichlorophenylmercapturic acid as a minor metabolite (5% of the dose). 3. p-Dichlorobenzene (0.5 g./kg.) is mainly oxidized to 2:5-dichlorophenol which is excreted conjugated. 2:5-Dichloroquinol is also formed (about 6% of the dose) but in contrast with o-dichlorobenzene no mercapturic acid or dichlorocatechol is formed. 4. The excretion ofthe metabolites of o-dichlorobenzene is slow and appears to be complete in 5-6 days after dosing. With the para isomer, the excretion of metabolites is not complete and is still appreciable after 6 days.