Telomere length, telomerase expression, and oxidative stress in lead smelters.

The negative health effects caused by lead (Pb) exposure are widely recognized; however, the molecular mechanisms remain unknown. The aim of this study was to assess the effect of occupational Pb exposure on telomere length and to investigate the potential mechanisms leading to telomere shortening. A cohort of 334 male Pb smelters (exposed group) and 60 age-adjusted males unexposed to Pb (control group) were examined. Assessments of relative telomere length (rTL) and telomerase reverse transcriptase (TERT) gene expression were performed using quantitative real-time polymerase chain reactions. Assessments of whole blood Pb (B-Pb) and whole blood cadmium (B-Cd) concentrations and serum selenium concentration (S-Se) were performed using graphite furnace atomic absorption spectrometry. We analyzed total oxidation status (TOS), lipid hydroperoxides (LHPs), malonylodialdehyde levels in serum (MDA) and in erythrocyte hemolysates (MDA-hgb), and 8-hydroxy-deoxy-guanosine (8-OHdG). The Pb-exposed group had higher B...