Mutation Research, 272 (1992) 175-181 175 © 1992 Elsevier Science Publishers B.V. All rights reserved 0165-1161/92/$05.00 MUTENV 08843 Genotoxic potential of the organochlorine insecticide lindane (y-BHC)" an in vivo study in chicks S.P. Bhunya and G.B. Jena Laboratory of Genetic Toxicology, P.G. Department of Zoology, Utkal Unicersity, Bhubaneswar 751004, India (Received 28 January 1992) (Revision received 21 April 1992) (Accepted 28 April 1992) Keywords: Lindane; Chromosome aberration; Micronucleus; Chicks Summary The purpose of this work was to evaluate the genotoxic potential of lindane (v-isomer of benzene hexachloride (BHC)) in chicken in vivo tests: the bone marrow chromosome aberration and micronucleus tests. With the highest dose (100 mg/kg) a significant enhancement of chromosome aberrations was noticed after 24 and 48 h and with the second highest dose (75 mg/kg) after 24 h. A significant increase in the incidence of micronuclei in bone marrow cells was induced by all three doses (100, 75 and 50 mg/kg) given either intraperitoneally or orally while in peripheral erythrocytes only the two higher intraperitoneal doses (100 and 75 mg/kg) gave significant increases. On the basis of these results, lindane may be considered genotoxic in this test system and it is suggested that the chick in vivo system may be used as an alternative to a mammalian system for screeining environmental chemicals for genotoxocity. Microbial and mammalian systems are often used to screen for genotoxicity of environmental agents. However, in recent years encouraging re- suits have also been obtained using embryonic and neonatal chicks for screening for chemically induced cellular and genetic damage (Bloom, 1982; Dietert et al., 1985; Nikolaides et al., 1988; Sawyer et al., 1986; Todd et al., 1980). Chick embryos have also been used for teratogenicity studies (Gebhardt, 1972). So far, the post-hatch- ing chick system has not been exploited much for testing the mutagenicity of environmental agents. Correspondence: Dr. S.P. Bhunya, Reader in Zoology, Utkal University, Bhubaneswar 751004, Orissa, India. It is easier to handle and rear chicks than mammals. The low cost of chicks and the wide selection of strains and genotypes, etc., make the present system attractive for experimentation. In cytological preparations, the macrochromosomes are easily recognisable and chromosomal sexing of cells is very easy. Unlike mammalian erythro- cytes, chicken erythrocytes are nucleated, which makes it possible to study nuclear anomalies in peripheral blood. Lindane (y-isomer of benzene hexachloride (BHC)) is a potent insecticide employed for agri- cultural and medicinal purposes (Solomon et al., 1977). Like other organochlorine compounds it enters animal tissues through the food chain, inhalation into lungs or by direct diffusion through