Genotoxicity study in lymphocytes of workers in wooden furniture industry

We have evaluated the extent of genetic damage (frequencies of sister chromatid exchange (SCE) and micronuclei) in blood lymphocytes and found a correlation between exposure period and genetic damage, in workers in the wooden furniture industry. Venous blood samples were drawn from thirty nonsmoking workers exposed to wood dust and thirty non-smoking controls. Lymphocytes were cultured for 72 h and at the end of the culture time the cells were harvested, stained and coded for blind scoring. Damage to the genetic material was evaluated by counting the number of SCEs in 100 metaphases and the frequency of micronuclei in 1000 binucleated cells. Mitotic and proliferative rate indices were also determined. Environmental studies showed a dust level of 0.30 mg/m(3) (particle size 2.5 microns). The mean micronuclei frequency was significantly higher in the exposed group (17.2%; SD = 1.17, P < 0.001; range 13-21.1) compared to the controls (7.54%; SD = 1.6, P < 0.001; range 5-10.5). The mean value of SCEs was also higher (7.17, SD = 1.80) in the exposed workers than in the controls (6.71, SD = 1.56), but the difference was not statistically significant. A positive correlation existed between the duration of exposure and micronucleus frequency (correlation coefficient, gamma = 0.64) and SCE (correlation coefficient gamma = 0.47). These results indicate that occupational exposure to wood dust causes genetic damage, which may lead to health hazards like cancer, with or without other risk factors.