Toxicology Letters 121 (2001) 15 – 20 Genotoxic effect of hydroquinone on the cultured mouse spleenocytes Ganesh Chandra Jagetia *, K.S. Lakshmy Menon, Vikas Jain 1 Department of Radiobiology, Kasturba Medical College, 3rd Floor, Karnataka, Manipal 576 119, India Received 18 July 2000; received in revised form 18 October 2000; accepted 18 October 2000 Abstract The daily administration of 0, 0.5, 1, 2, 4 and 8 mg/kg b. wt. of hydroquinone (HQ) to Swiss albino mice, consecutively for 6 days resulted in a dose dependent elevation in the frequency of micronucleated binucleate spleenocytes (MNBNS). This increase in the frequency of MNBNS was significantly higher than that of non-drug treated controls (0 mg/kg). The daily administration of various doses of HQ for 6 days not only increased the frequency of binucleated spleenocytes bearing one micronuclei (MN), but also the BNS bearing two, three, and four MN. The study demonstrates that the daily administration of various doses of HQ for 6 days increases the genotoxic and mutagenic potential in mice. © 2001 Elsevier Science Ireland Ltd. All rights reserved. Keywords: Hydroquinone (HQ); Micronuclei (MN); Spleenocyte; Mice www.elsevier.com/locate/toxlet 1. Introduction Human beings may be exposed to various haz- ardous chemicals that are carcinogens or muta- gens. Hydroquinone (HQ) is one among them. It is used in various industries as antioxidant or stabilizer for certain materials, production of an- tioxidants, antiozonants, agrochemicals and poly- mer industry (Varagnat, 1981). HQ is used as a developer in black and white photography and related graphic arts such as lithography, ro- togravure and for medicinal and industrial X-ray films (Varagnat, 1981). HQ and products contain- ing HQ are used in cosmetics, medical skin prepa- rations as depigmenting agent and also to treat melasina, freckles, senile lentigines and post-infl- ammatory hyperpigmentation (Varagnat, 1981; CIR, 1986). Human exposure to HQ is mainly by the con- sumption of plants and animal derived food prod- ucts and also by using cosmetics and medical preparations containing HQ. It is also found in cigarettes (IARC, 1986) and brewed coffee (De- ichmann and Keplinger, 1981). HQ is a benzene metabolite and it has been implicated in the devel- opment of aplastic anaemia, leukemia and other * Corresponding author. Tel.: +91-8252-71200, ext. 2122; fax: +91-8252-70062. E-mail address: jagetia-vip@zetainfotech.com (G.C. Jage- tia). 1 Present address: Magan Kunj, BE/2 (West) Shalimar Bagh, Delhi 110 052, India. 0378-4274/01/$ - see front matter © 2001 Elsevier Science Ireland Ltd. All rights reserved. PII:S0378-4274(00)00290-3