MUTAGENICITY OF ETHYL CARBAMATE TO LACZ- TRANSGENIC MICE

The mutagenicity of the rodent carcinogen ethyl carbamate (EC, urethan e) has been assessed using the lacZ(-) transgenic mouse mutation assay (Muta (TM) Mouse). In two separate experiments a single i.p. dose of 900 mg/kg urethane followed by a 14-16 day expression period yielded s tatistically significant (similar to 2-fold) increases in mutation fre quency (MF) in the lung and liver of the mice. In the second experimen t MF in the spleen and bone marrow was also assessed and statistically significant increases in MF were observed in each case. Concomitantly conducted bone marrow micronucleus assays gave 15.8- and 8-fold incre ases respectively in the incidence of micronucleated polychromatic ery throcytes in the two studies.