Research Article Association of Polymorphisms of Phase I Metabolizing Genes with Sister Chromatid Exchanges in Occupational Workers Exposed to Toluene Used in Paint Thinners Kanu Priya, 1 Anita Yadav, 1 Neeraj Kumar, 1 Sachin Gulati, 1 Neeraj Aggarwal, 2 and Ranjan Gupta 3 1 Department of Biotechnology, Kurukshetra University, Kurukshetra, Haryana 136119, India 2 Department of Microbiology, Kurukshetra University, Kurukshetra, Haryana 136119, India 3 Department of Biochemistry, Kurukshetra University, Kurukshetra, Haryana 136119, India Correspondence should be addressed to Anita Yadav; ayadav@kuk.ac.in Received 11 September 2015; Revised 2 November 2015; Accepted 9 November 2015 Academic Editor: Martin Kupiec Copyright © 2015 Kanu Priya et al. Tis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Tis study investigated genetic damage in paint workers mainly exposed to toluene as it is a major solvent used in paint thinners. Sister chromatid exchange (SCE) assay was used as biomarker of genotoxicity. Blood samples were collected from 30 paint workers and 30 control subjects matched with respect to age and other confounding factors except for exposure to toluene. SCE frequency was found to be signifcantly higher in paint workers (4.81 ± 0.92) as compared to control individuals (1.73 ± 0.54)( < 0.05). We also investigated infuence of polymorphisms of CYP2E1 and CYP1A1m2 genes on SCE frequency. Our results showed that there was signifcant increase in frequencies of SCE among the mutant genotypes of CYP2E1 and CYP1A1m2 as compared to wild genotypes. Our study indicated that long term exposure of toluene can increase genotoxic risk in paint workers. 1. Introduction Organic solvents, a class of chemical genotoxic agents, are mainly used in petrol pumps (benzene, xylene, naphtha- lene, and 1,2,4-trimethylbenzene), dry cleaning (e.g., tetra- chloroethylene), as paint thinners (e.g., toluene, turpentine), and so forth. Te exposure of organic solvents can lead to euphoria and hallucinations while high doses may produce life-threatening efects such as convulsions and coma. Te long term exposure may lead to cancer risk [1]. Paint workers utilize a variety of chemicals including dyes, solvents (thin- ners), and fnishing chemicals. Toluene is a major solvent used in paint thinners. Given its relatively high volatility, it is predicted that 99 per cent toluene released into the environment is present in the atmosphere. Inhalation of toluene depresses the nervous system. Te major efects on humans following acute exposure to high concentrations of toluene include central nervous system dysfunction and unconsciousness. Death can occur in extreme cases. Liver and kidney injury may also occur with exposure to high con- centrations. Occupational exposure to moderate levels has been associated with fatigue, sleepiness, headaches, nausea, and decreased manual dexterity and visual perception. Various kinds of biomarkers have been applied for bio- logical monitoring of exposed population. Te examples of such biomarkers include cytogenetic changes (structural and numerical changes in chromosomes, micronuclei for- mation, sister chromatid exchanges, etc.), somatic muta- tions, and changes in tumor suppressor genes. Sister chro- matid exchanges (SCEs) are interchanges of DNA replication products between sister chromatids at apparently homolo- gous loci, suggested to represent homologous recombination repair of DNA double strand breaks [2, 3]. Biomarkers of susceptibility are indicators of an inherent or acquired ability of an organism to respond to the challenge of exposure to a specifc chemical substance. Tese biomarkers provide an indication of the extent to which an individual may be prone to progress from exposure to developing an adverse health Hindawi Publishing Corporation Genetics Research International Volume 2015, Article ID 630296, 5 pages http://dx.doi.org/10.1155/2015/630296