Chemical changes of organic compounds in chlorinated water. XI. Thin-layer chromatographic fractionation of Ames mutagenic compounds in chlorine-treated 4-methylphenol solution.

The diethyl ether extract from an aqueous solution of 4-methylphenol after treatment with hypochlorite was mutagenic to the Ames Salmonella test strain TA100 in the absence of liver homogenate. Gas chromatography-mass spectrometry (GC-MS) showed the occurrence of, at least, twenty compounds in the extract: chloro-4-methylphenols, chlorohydroxy-4-methylquinones and chlorinated 4-methylphenol dimers. The diethyl ether extract was fractionated into several fractions by silica gel and polyamide thin-layer chromatography (TLC). The fractionated components were then examined for mutagenicity by means of Ames assays, and were identified by GC-MS. TLC fractionation of the extract revealed that the major components present in the extract are not mutagenic, but minor components (less than 4% of the total extract) are mutagenic. GC-MS analysis indicated the presence of chlorinated 4-methylphenol dimers in the fraction which exhibited the highest mutagenicity.