Determination of genotoxicity in silicotic patients characterized with occupational exposure to crystalline silica

Occupational exposure to crystalline silica (quartz) results to the silicosis disease. Quartz has been classified as human carcinogen in 1997. Denim-blasting is one of the working area in which there could be the highest exposure to quartz. Although this working area, which has caused many young silicosis patients has been banned in our country, still it is critically important.Our aim is, to give support the research investigating the relationship between silicosis and lung cancer by determining the genotoxic risk in silicosis patients.The silicosis patients (n=15) worked in denim-blasting have been engaged to our study. They have been diagnosed with their X ray chest films. The control group consisted of healthy volunteers (n=15). Micronucleus (MN) Assay has been carried in peripheral blood lymphocytes (PBL) and in cells from sputum induction (SI). The mean work duration of the workers was (mean ±sd) 3,767±1,821 years. Nine of the silicosis patients were in group 3 according to the ILO classification.The MN frequency in PBL of workers (4.333±2.160) were found to be statistically significantly higher vs. the control group (1.733±1.710) (p<0.05). In the same manner, SI MN frequency in workers (11.000±4.743), were statistically significantly higher vs. the control group (3.778±2.386) (p<0.05). It has been observed that smoking had increasing effect for MN frequency in both of the tissues.As a conclusion it is the first study using SI-MN assay regard to quartz exposure. With our study, it has been established that to have silicosis increased the MN frequency thus the genotoxic risk. In this respect, this result supports the relationship between the silicosis and lung cancer.