职业性射线接触者外周血淋巴细胞DNA损伤的动态观察

Dynamic observation on DNA damage in peripheral blood lymphocytes of workers occupationally exposed to ionizing radiation

目的 了解长期小剂量、低剂量率职业性射线接触者的细胞DNA损伤动态变化。方法 用单细胞微量凝胶电泳 (SCGE)对某厂 80名职业性射线接触人员于 1996～ 2 0 0 0年连续 5次作DNA损伤检测。结果 在暴露的平均年当量剂量范围内 ,射线接触组DNA受损细胞率与对照组相比 ,均有显著增加 ,但接触组平均DNA受损细胞率未见有明显逐年升高的趋势 ;DNA受损细胞率与放射工龄、年龄、平均年当量剂量有明显的相关性 ,随放射工龄的增加呈递增趋势。结论 长期受小剂量、低剂量率照射的职业性射线接触者会引起外周血淋巴细胞DNA损伤持续改变 ;且DNA受损细胞率随放射工龄、年龄、平均年当量剂量的增加呈递增趋势。SCGE可用于低剂量电离辐射引起的DNA损伤动态研究与评价。

Objective In order t o investiga te the dynamic change of DNA damage induced by ionizing radiation,the singl e cell gel electrophoresis(SCGE)was car ried out in workers exposed to radiation for many years.Method The le ngth and ra te of DNA migration of peripheral blood lymphocytes of exposed workers were anal yzed in 1996,1997,1998,1999 and 2000. Res ult The significantly different le ngth of DNA migration and DNA damage cell rate were exhibited between the observed and control groups(P<0.05),and the level of DNA damage was increasing after exposed to long,small dose radiation.In the mean of annual dose equivalent of exposed ra diation,no elevated trend of DNA damage cell rate was observed in the continuou s years.Significant associations were ob served between the DNA damage cell rate and radiation service length,age,average annual dose equivalent.Conclusion These findings suggest that the technique of SCGE could be used to detect dynamically the earliest biological damage by ioniz ing radiation in exposed workers.