MUTAGENICITY OF OZONATED AND CHLORINATED HUMIC SUBSTANCES

Humic substances were ozonated and subjected to the mutagenicity assay with Salmonella typhimurium TA 98 and 100. Both of ozonated humic sub stances and their dichloromethane extracts were not mutagenic. Then, o zonated humic substances were chlorinated, extracted with ether at pH 7 and 1.5, and subjected to the mutagenicity assay. Both of the ether extracts found to be mutagenic on TA 100. The ozonation and ozonation- chlorination products of humic substances were determined by gas chrom atography-mass spectrometry (GC-MS) and mutagenic aldehydes were ident ified.