DNA single- and double-strand breaks by alkaline- and immuno-comet assay in lymphocytes of workers exposed to styrene.
Occupational exposure to styrene was studied in 34 workers employed in the production of fiberglass-reinforced plastic sheets and compared to 29 unexposed healthy controls. We evaluated genotoxic effects induced by occupational styrene exposure in lymphocytes by alkaline version of the comet assay to detect single-strand breaks (SSBs), DNA oxidation products (formamido pyrimidine glycosilase (Fpg)- and endonuclease (Endo III)-sensitive sites) and DNA repair kinetics studies, as well as the neutral version of comet assay for DNA double-strand breaks (DSBs). An innovative aspect of this study was the use of immuno-comet assay, a new technique that recognizes DSBs with specific antibody by DAPI/FITC method. The battery of parameters included markers of external and internal exposure. Exposed workers showed significant high levels of SSBs (p<0.0001) and DSBs (p<0.0001) in neutral- and immuno-comet assay. A drastic decrease in DNA repair activity as compared to controls was observed (180 min vs. 35 min). Styrene workplace concentration significantly correlated with alkaline comet parameters (TM, p=0.013; TI, p=0.008), in negative with TL (p=0.022), and with DNA-base oxidation (TM Endo III, p=0.048 and TI Endo III, p=0.028). There was a significant negative correlation between urinary metabolites (MA+PGA) and TM Endo III (p=0.032) and TI Endo III (p=0.017).
Fracasso
Maria Enrica
ME
Department of Medicine and Public Health, Section of Pharmacology, University of Verona, Policlinico GB Rossi, P.le Scuro 10, 37134 Verona, Italy. mariaenrica.fracasso@univr.it
Doria
Denise
D
Carrieri
Mariella
M
Bartolucci
Giovanni Battista
GB
Quintavalle
Sonia
S
De Rosa
Edoardo
E
D000328:Adult; D015415:Biomarkers; D020552:Comet Assay / Q000379:methods*; D053903:DNA Breaks, Double-Stranded / Q000187:drug effects*; D053904:DNA Breaks, Single-Stranded / Q000187:drug effects*; D004260:DNA Repair; D006801:Humans; D008214:Lymphocytes / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D016273:Occupational Exposure / Q000009:adverse effects*; D020058:Styrene / Q000009:adverse effects*
D015415:Biomarkers; D020058:Styrene