标题：The Mutagenic and Some Physico-Chemical Properties of Organic Residues Obtained from Drinking Water by Amberlite XAD-2 and Activated Carbon Extraction
摘要：Several types of drinking-water organic residues, obtained by solvent extractions from XAD-2 resin and activated carbon columns after the passage of drinking water (10 m3), were tested for mutagenic activity in TA-98 and TA-100 strains with and without the addition of S9. Direct-acting mutagens and some substances toxic to the tester strains were found to be present in these organic residues. Thin-layer chromatographic (TLC) fractionations, using polyamide plates, coupled with bioassay for mutagenicity showed that some of the major mutagens present in the XAD-2-extractable organic residues were of intermediate polarity and some were nonpolar. In contrast, those mutagens found in carbon-ether-extractable residues behaved on the TLC plates as compounds with a wide polarity range, with the strongest mutagenicity appearing among the acidic substances. Mutagenicity of these residues was inactivated by incubation with 4-nitrothiophenol as a nucleophile, but no change in activity was observed following reaction with o-phenylenediamine as a trapping reagent for mutagenic α-carboxylic compounds. In addition, it was found that mutagenicity in these organic residues was rapidly lost following heating, light irradiation or addition to alkaline solutions.
