Effect of genotoxic exposure to chromium among electroplating workers in Taiwan.

The objective of this study was to investigate the association between chromium (Cr) concentrations and sister chromatid exchanges (SCE) formation in Cr workers and to assess the effects of susceptible genes (glutathione S-transferase M1 and T1) on the frequency of deletion and SCE/cell. Urinary Cr concentration was significantly elevated in Cr workers (3.67 +/- 3.89 microg/g creatinine) compared to control group (1.21 +/- 1.16 microg/g creatinine, P < 0.01). There was also a significant difference of superoxide dismutase (SOD) levels between Cr workers (6.86 +/- 0.80 U/mg Hb) and controls (7.16 +/- 0.53 U/mg Hb, P < 0.01). The frequencies of SCE and high frequency cells (HFC) were significantly correlated with smoking habits and with duration of exposure to Cr. A significantly higher percentage (50%) of Cr workers had both the null GSTM1 and GSTT1 genotype as compared to 10% of the controls (P < 0.01). However, the chromosomal DNA damage effect of GSTM1 and GSTT1 genotypes, individually or in combination, was not revealed in Cr exposed workers.