 Statistical analysis Statistical analysis was done by using SPSS software package IBM Corp., Armonk, NY, USA. By descriptive statistical analysis, the basic statistical parameters mean, standard error, and standard deviation, and relative standard deviation, median and minimum and maximum values were determined. The differences in the number of micronuclei and other nuclear anomalies between different sampling times for each group and between the groups of examinees were tested by ANOVA and Tukeys HSD post hoc test using a general linear model procedure. General regression model GRM from linearnonlinear modelling method was used for the assessment of the influence of the predictor variables age, gender, and profession, use of medication, X-ray exposure, dietary habits, and lifestyle onto dependent variables micronucleus, binucleated cells, broken eggs, nuclear buds, pyknosis, condensed chromatin, karyolysis and karyorrhexis. The results of GRM are expressed in the form of Pareto charts of t values. A significance level was set at 0.05. 