engleski

Influence of smoking, folic acid and vitamin B12 concentration on DNA stability in lymphocytes from workers occupationally exposed to low levels of ionizing radiation

Bleomycin sensitivity test in peripheral lymphocytes was used to compare the results of 28 individuals occupationally exposed to low levels of ionizing radiation and 28 matched controls, and to search for correlation with smoking habits, folic acid and vitamin B12 concentrations. Statistical significance of the results was tested by non-parametric Mann-Whitney test. Mean duration of occupational exposure to ionizing radiation was 12.43± ; 9.11 years (range: 1-38). The mean break/cell (b/c) for the controls was 0.60± ; 0.27 and exposed workers 0.51± ; 0.26, (p>0.01). Gender did not significantly influence the values of endpoints studied, although slightly higher folic acid concentrations have been observed in women (8.76± ; 3.64 µ ; g/l). In control group higher values for folic acid (control:8.59± ; 4.08 µ ; g/l vs. exposed: 6.49± ; 2.87 µ ; g/l) and vitamin B12 (control: 485.89± ; 160.03 ng/l vs. exposed: 424.62± ; 156.33 ng/l) were observed. Concentration of folic acid in smokers was in significant negative correlation with b/c (Spearman R=-0.57 ; p=0.0049), and age respectively (Spearman R=-0.59 ; p=0.0033). Gender-related differences in b/c values were observed in control group, both in smokers (men: 0.67± ; 0.17 vs. women: 0.36± ; 0.26 ; p=0.055) and non-smokers (men: 0.80± ; 0.25 vs. women: 0.44± ; 0.19 ; p=0.0088). Among exposed non-smokers we also observed significant difference regarding to gender (men: 0.55± ; 0.14 vs. women: 0.39± ; 0.14 ; p=0.021). The results obtained point to the value of bleomycin sensitivity test in human biomonitoring and confirmed gender and dietary habits as important factors involved in DNA damage response.

ionizing radiation; low level doses; folic acid; vitamin B12;

Workshop 14: Exogenous and Endogenous Background Exposures to Carcinogens and Regulatory Consequences ; Poster Presentations S32-S89, P3: Risk Assessment