DETECTION OF IN-VIVO GENOTOXICITY OF CHLORO-4-(DICHLOROMETHYL)-5-HYDROXY-2[5H]-FURANONE (MX) BY THE ALKALINE SINGLE-CELL GEL-ELECTROPHORESIS (COMET) ASSAY IN MULTIPLE MOUSE ORGANS

We tested the genotoxicity of chloro-4-(dichloromethyl)-5-hydroxy-2[5H ]-furanose (MX) in the mouse in 6 organs (liver, lung, kidney, brain, spleen, and bone marrow) and in the mucosa of stomach, jejunum, ileum, colon, and bladder using the alkaline single-cell gel electrophoresis (SCG) (Comet) assay modified by us. Mice were sacrificed 1, 3, 6, and 24 h after oral administration of the mutagen at 100 mg/kg. MX yielde d statistically significant DNA damage in the liver, kidney, lung, and brain and in all the mucosa samples. While DNA damage persisted in th e gastrointestinal and urinary tract for 6-24 h after a single oral do sing, it peaked in the liver at 1 h and returned to almost the control level at 3 h. Our present results suggest that MX is genotoxic for va rious mouse organs, but not for the hematopoietic system, and that the alkaline SCG assay with a homogenization technique can be used to pre dict genotoxicity in the gastrointestinal and urinary tracts. (C) 1997 Elsevier Science B.V.