Abstract: BACKGROUND ＆ AIM: To assess the mutagenic effects of bituminous , anthracite , lignite dust. MATERIALS AND METHODS: The mutagenicity of the dust and their mixture with benzo(a)pyrene suspension(pH 6.5－7.0) was investigated by Salmonella typhimurium/reverse mutation assay(Ames test) and sister chromatid exchange (SCE) test both with and without S9 activation. According to the Ames test specification, TA97,TA98,TA100 and TA102 strains were used and the ammounts of 3 kinds of dust and their mixture with benzo(a)pyrene were 5000,500,50 and 5 μg/plate, respectively. The number of colony was counted after culturing for 48 h at 37 ℃. SCE test was performed with peripheral blood lymphocytes of healthy men. The ammounts of 3 kinds of dust and their mixture with benzo(a)pyrene were 500, 50 and 5 μg/plate, respectively .The chromosome specimen slide was made after culture 72 h at 37 ℃ and the frequency of SCE was counted.There were triplicate plates in each group and negative and positive controls were set up in Ames and SCE tests. RESULTS: The colony number of 3 kinds of dust were not more than twice of that of spontaneous recovery mutation (SRM) both with and without S9 activation. There was no dose_response relationship among groups. The colony number of the coal dust mixture with benzo(a)pyrene was not significantly higher compared with that of benzo(a)pyrene alone(P>0.05). The SCEs of coal dust and their mixture with benzo(a)pyrene were not increased significantly compared with control group. CONCLUSION: Mutagenicity of the 3 kinds of coal dust and their mixture with benzo(a)pyrene were not found under these conditions.

Key words: coal dust, mutagenicity, Ames test, sister chromatid exchange