Selective induction of micronuclei in the rat/mouse colon and liver by 1,2-dimethylhydrazine: a seven-tissue comparative study.

1,2-Dimethylhydrazine (DMH) was administered to both genders of mice and rats by oral gavage for 3 days. Twenty-four hours later, an assessment of the incidence of micronucleated cells was made in the bone marrow and sections of the gastrointestinal tract. An increase in micronucleated cells was observed in the colon of both genders of both species of rodent.

Genotoxicity and carcinogenicity testing of 1,2-dibromopropane and 1,1,3-tribromopropane in comparison to 1,2-dibromo-3-chloropropane.

The activities of 1,2-dibromopropane (DBP) and 1,1,3-tribromopropane (TBP) were studied in seven genotoxicity assays, (i) SOS-induction in E. coli, (ii) DNA repair in primary rat hepatocyte culture, (iii) the Salmonella/microsome assay, (iv) a host-mediated assay using Salmonella, (v) the somatic mutation and recombination assay in Drosophila melanogaster, (vi) HGPRT-mutagenesis assay in ARL 18 cells, and (vii) micronucleus formation assay in mouse polychromatophylic erythrocytes (PCE), forestomach (FS), glandular stomach (GS), duodenum (D), jejunum (J), cecum (C) and liver (L). The halopropanes were also tested for tumor formation in the fish Danio rerio.

[Mutagenic activity of the fungicide captan].

A complex study of mutagenic activity of captan (a fungicide) in a series of standard test-systems has shown that the preparation induces gene mutations in certain Salmonella indicator strains (without metabolic activation), increases the frequency of mitotic crossing-over and gene conversion in yeasts (Saccharomyces), possesses a weak cytogenetic action on bone marrow cells in experimental animals, manifests no cytogenetic effect in the lymphocyte culture of human peripheral blood (including a system of microsomal activation). Genetic activity of captan cannot be a limiting criterion of its harmfulness.

[Effect of phenobarbital on the cytogenetic activity of cyclophosphamide].

The effect of phenobarbital (PB, 2 and 80 mg/kg, 3 intraperitoneal injections) on the rate of chromosomal aberrations in the bone marrow cells of rats induced by a single intraperitoneal injection of cyclophosphamide (CP) in a dose of 25 mg/kg was studied. Activity of mixed function oxygenase (MFO) was evaluated from the content of cytochrome P450, b5 and activity of aniline hydroxylase. The rate of the cells with chromosomal aberrations in the bone marrow after combined action of PB and CP did not depend on the PB dose and was significantly higher as compared with CP action alone.