Mutation Research 521 (2002) 11–17 Clastogenicity of carbazole in mouse bone marrow cells in vivo A.M. Jha ∗ , Akhilesh C. Singh, M. Kumari Bharti Genetic Toxicology Laboratory, Department of Botany & Biotechnology, Samastipur College, Samastipur 848 134, India Received 18 January 2002; received in revised form 23 July 2002; accepted 23 July 2002 Abstract Clastogenicity of carbazole was evaluated by employing mouse in vivo chromosomal aberration (CA) test. Carbazole administered intraperitoneally (i.p.) at the rate of 25, 50, 100, 150 and 200mg/kg b.w. to Swiss albino mice in vivo resulted in mitotic depression and induction of chromosomal aberrations. Dose related decrease in mitotic index (MI) and increase in the frequencies of chromosomal aberrations per cell (CAs/cell) and percent abnormal cells were recorded in bone marrow cells. However, statistically significant reduction in MI and increase in CAs/cell and percent abnormal cells were found only for the two higher doses. The results obtained indicate that carbazole or its metabolite, if any, is moderately clastogenic in the bone marrow cells of Swiss albino mice. © 2002 Elsevier Science B.V. All rights reserved. Keywords: Clastogenicity; Carbazole; Mitotic index; Chromosomal aberration; Bone marrow cells 1. Introduction Carbazole (dibenzopyrrole, diphenylenimine, CAS No. 86-74-8, M.W. 167.2, C 12 H 9 N) is used in the man- ufacture of dyes, reagents, explosives, insecticides, lubricants, rubber antioxidants and as odor inhibitors in detergents, etc. [1]. According to IARC monograph [2], the compound is present as a major component of total content of polynuclear aromatic compounds in the environment arising primarily from the combus- tion of tobacco and coal. Carbazole and several of its derivatives has been detected as a major component of cigarette smoke condensate [3,4]. Therefore, humans are always unavoidably exposed to this compound in various situations. The compound has been tested for carcinogenicity in mice by administration in diet, by skin application and by subcutaneous injection. Dose dependent increase in the incidence of liver neoplastic ∗ Corresponding author. Fax: +91-6274-23720. E-mail address: jhaanandmohan@yahoo.co.uk (A.M. Jha). nodules and hepatocellular carcinomas were ob- served. Papillomas and carcinomas of forestomach occurred in animals receiving high dose level of this compound [2,5]. However, this compound has been found non-mutagenic in Salmonella typhimurium [2]. Carbazole treatment resulted in depression in the re- productive performance of male mice and induced dominant lethal mutations and statistically significant increase in the percentage of abnormal sperm heads in mouse [6]. Therefore, an attempt was made to evaluate the clastogenic property of this compound in the bone marrow cells in vivo in mouse by employing chromosomal aberrations (CA) test. 2. Material and methods 2.1. Animals Laboratory bred Swiss albino male mice (Mus mus- culus), aged 6–8 weeks and weighing 28–30 g were 1383-5718/02/$ – see front matter © 2002 Elsevier Science B.V. All rights reserved. PII:S1383-5718(02)00210-3