CHARACTERIZATION OF CHLORINATED AROMATIC STRUCTURES IN HIGH-MOLECULAR-WEIGHT BKME-MATERIALS AND IN FULVIC-ACIDS FROM INDUSTRIALLY UNPOLLUTED WATERS

This paper presents the results of a comprehensive characterization of chlorinated aromatic structures in high molecular weight organic mate rial from bleached kraft mill effluents (BKME) and industrially unpoll uted surface waters and groundwaters. After oxidative degradation (per manganate) of the organic materials and derivatization (diazomethane) of the degradation products obtained, the occurrence of chlorinated ar omatic degradation products was investigated using gas chromatography/ mass spectrometry. About twenty chlorinated methyl esters of aromatic carboxylic acids were identified in degraded samples of both industria l and natural origin. The identified compounds originated from chlorin ated 4-hydroxyphenyl, 3,4-dihydroxyphenyl, guaiacyl, ''condensed'' gua iacyl, syringyl and veratryl units present as structural elements in t he high molecular weight organic materials studied. Degradation produc ts originating from mono- and dichlorinated 4-hydroxyphenyl units domi nated in the degraded samples from unpolluted environments, whereas de gradation products originating from chlorinated guaiacyl and syringyl units were most abundant in the degraded softwood and hardwood BKME sa mples. A special study of the monochlorinated isomers of 4-ethoxy-3-me thoxybenzoic acid methyl ester showed that the 6-chloro isomer dominat ed in the degraded BKME samples whereas about equal amounts of the 5-c hloro and 6-chloro isomers were found in degraded fulvic acids isolate d from unpolluted waters.