1-Methyl-2-pyrrolidinone (NMP) does not induce structural and numerical chromosomal aberrations in vivo.

1-Methyl-2-pyrrolidinone induces aneuploidy in yeast, but only under special treatment conditions. Other genotoxic effects have not been found in vitro, and in vivo no data are available in the literature. Therefore, NMP was investigated in the mouse micronucleus test and the Chinese hamster bone marrow test for structural and numerical chromosomal aberrations. These tests can detect both types of alterations as demonstrated by appropriate positive control substances (cyclophosphamide, vincristine sulfate and benomyl). NMP at single oral doses up to 3800 mg/kg body weight (approximately 80% of the LD50) did not lead to an increase either in micronucleated erythrocytes or in structural or numerical chromosomal aberrations when bone marrow was sampled 16, 24 and 48 h after treatment in the micronucleus test or after 24 and 48 h for karyotype analysis.