MUTAGENICITY AND CLASTOGENICITY OF CHLORO-4-(DICHLOROMETHYL)-5-HYDROXY-2(5H)-FURANONE (MX) IN L5178Y TK+/--3.7.2C MOUSE LYMPHOMA-CELLS/

chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX) was tested wit hout exogenous activation in L5178Y/TK+/--3.7.2C mouse lymphoma cells for mutation at the thymidine kinase locus and for clastogenicity. At a concentration of 0.75 mu g/ml, the induced mutant frequency was 1027 per 10(6) survivors (survival=11%). A concentration-related increase of large and small colony mutants was observed, but the majority of th e MX induced mutants formed small colonies, consistent with the positi ve clastogenic response that was observed. MX primarily induced chroma tid breaks and rearrangements (30 chromatid and 4 chromosome aberratio ns per 100 cells) at the 0.75 mu g/ml dose. These studies indicate tha t MX induces a broad spectrum of genetic damage.