ORIGINAL ARTICLESCytogenetic biomarkers, urinary metabolites and metabolic gene polymorphisms in workers exposed to styreneMigliore, Luciaa; Naccarati, Alessioa; Coppedè, Fabioa; Bergamaschi, Enricob; De Palma, Giuseppeb; Voho, Anuc; Manini, Paolab; Järventaus, Hilkkac; Mutti, Antoniob; Norppa, Hannuc; Hirvonen, AricAuthor Information aDepartment of Human and Environmental Sciences, University of Pisa, Italy bLaboratory of Industrial Toxicology, University of Parma, Italy cLaboratory of Molecular and Cellular Toxicology and Biomonitoring Laboratory, Department of Industrial Hygiene and Toxicology, Finnish Institute of Occupational Health, Helsinki, Finland Correspondence and reprint requests to Professor Lucia Migliore, Department of Human and Environmental Sciences, University of Pisa, Via S. Giuseppe 22, 56126 Pisa, Italy Tel: +39 050 836223; fax: +39 050 551290; e-mail: [email protected] Sponsorship: This work was supported by EC, contract QLK4-CT-1999-01368 (Genetic polymorphisms and biomonitoring of styrene; SUCEPTSTYRENE), the Italian Ministero del Lavoro e della Previdenza Sociale, research project no. 1096 (Impiego di nuove metodologie per la valutazione del rischio genetico in spermatozoi di lavoratori esposti professionalmente), and the Academy of Finland. Received 24 June 2005 Accepted 6 September 2005 Pharmacogenetics and Genomics: February 2006 - Volume 16 - Issue 2 - p 87-99 doi: 10.1097/01.fpc.0000182783.70006.44 Buy Metrics Abstract The present study comprised a biomonitoring study in 95 workers occupationally exposed to styrene and 98 unexposed controls, employing an integrated approach involving biomarkers of exposure, effect, and susceptibility. Airborne styrene was evaluated at workplace, and urinary styrene metabolites, mandelic acid (MA), phenylglyoxylic acid (PGA), vinylphenols (VPTs) and phenylhydroxyethylmercapturic acids (PHEMAs), were measured as biomarkers of internal dose. Cytogenetic alterations were evaluated by analysing the frequency of chromosomal aberrations (CAs) and micronucleated binucleated cells (MNBN) in peripheral blood lymphocytes. The micronucleus assay was coupled with centromeric fluorescence in situ hybridization to distinguish micronuclei (MN) arising from chromosomal breakage (C− MN) from those harboring whole chromosomes (C+ MN). The possible influence of genetic polymorphisms of xenobiotic-metabolizing enzymes involved in styrene biotransformation (EPHX1, GSTT1, GSTM1, GSTP1) and NAT2 on the cytogenetic endpoints was investigated. The exposed workers showed a significantly higher frequency of MNBN (13.8±0.5% versus 9.2±0.4%; P<0.001) compared to control subjects. The effect appeared to concern both C− and C+ MN. A positive correlation was seen between the frequency of C+ MN and urinary level of MA+PGA (P<0.05) and VPTs (P<0.001). Chromosome-type CAs positively correlated with airborne styrene level and VPTs (P<0.05), whereas chromatid-type CAs correlated with PHEMAs (P<0.05). Workers bearing GSTM1 null genotype showed lowered levels of PHEMAs (P<0.001). The GSTT1 null genotype was associated with increased MNBN frequencies in the exposed workers (P<0.05) and the fast activity EPHX genotype with a moderate decrease in both MNBN and CAs in the controls. Our results suggest that occupational exposure to styrene has genotoxic effects that are potentiated by the GSTT1 gene deletion. These observations may have relevance considering the risk of lymphatic and haematopoietic malignancies tentatively associated with styrene exposure. © 2006 Lippincott Williams & Wilkins, Inc.