Trimethoprim, cigerette smoking and radition is known to have a clastogenic effects on chromosomes when applied to oneby one. In this study all of this aggents have been applied together. 8, 35 and 60 mg/ml doses of trimethoprim applied to the bloods which were taken from five healthy radiology technicians who are cigarette smokers, for the periods of 6, 24 and 48 hours. The same quantity of culture medium was added to the cultures which were separated for control in the same period. For each dose-aplication ;eriod combination, from each individual 50 metaphases were evaluated in relation to the ratio of "The Cells Including Chromosomal Aberrations" and "Structural Chromosome Abberrations". The ratio of cells including chromosomal aberration was 4.8 % for the control group, it was 11.6 % at 8 mg/ml, 14 % at the 35 mg /ml and 17.86 % at the 60 mg /ml. The ratio structural chromosome aberrations was 4.13 % for the control group, it was 11.73 at the 8 mg /ml, 15.33 % at the 35 mg /ml and 19.06 % at the 60 mg/ml. Statistical evaluat on of findigs showed that the ratio of choromosomal aberrations incereased parellel to the increased dose of tiremthoprim (p

Trimethoprim, cigerette smoking and radition is known to have a clastogenic effects on chromosomes when applied to oneby one. In this study all of this aggents have been applied together. 8, 35 and 60 mg/ml doses of trimethoprim applied to the bloods which were taken from five healthy radiology technicians who are cigarette smokers, for the periods of 6, 24 and 48 hours. The same quantity of culture medium was added to the cultures which were separated for control in the same period. For each dose-aplication ;eriod combination, from each individual 50 metaphases were evaluated in relation to the ratio of "The Cells Including Chromosomal Aberrations" and "Structural Chromosome Abberrations". The ratio of cells including chromosomal aberration was 4.8 % for the control group, it was 11.6 % at 8 mg/ml, 14 % at the 35 mg /ml and 17.86 % at the 60 mg /ml. The ratio structural chromosome aberrations was 4.13 % for the control group, it was 11.73 at the 8 mg /ml, 15.33 % at the 35 mg /ml and 19.06 % at the 60 mg/ml. Statistical evaluat on of findigs showed that the ratio of choromosomal aberrations incereased parellel to the increased dose of tiremthoprim (p