The tumorigenicity and transmissible genetic risk in mice under the Chernobyl simulation

为了模拟白俄罗斯中部污染地区（1997年、2005年）的放射性污染，将小鼠在放射性同位素设施中维持8个月，并免费获得含有^<137>CsCl （0Bq/ml、10Bq/ml和100Bq/ml）的饮用水。用γ-H2AX病灶定量测定受污染的放射性核素诱导的小鼠脏器DNA双链断裂，评价小鼠的长期低剂量率和低剂量内、外辐射效应。在相同条件下进行微核试验和小鼠肺致瘤性试验。每个肝细胞γ-H2AX病灶数分别为1.4 （0Bq/ml）、9.5（10Bq/ml）、10.7（100Bq/ml）。提示即使在低剂量污染区，体内低剂量^<137>Cs辐射引起的基因组损伤也是慢性发生的。而微核试验无显著性差异。此外，进展数据（每个剂量组6只动物）显示，相同条件下脲烷诱导的每只小鼠肺肿瘤数分别为36.8(368/10)（0 Bq/ml）、44.1 (441/10)（10Bq/ml）、44.1 (441/10)(100Bq/ml)，肿瘤直径（mm）平均值分别为1.64、1.67、1.68。

To simulate the radiocontamination in middle contaminated areas of Belarus (1997, 2005), mice were maintained for 8 months in the radioisotope facility with free access to drinking water containing ^<137>CsCl (0Bq/ml, 10Bq/ml and 100Bq/ml).Mice were assessed the long term low dose rate and low dose internal and external radiation effect by the quantitative measurement of the contaminated radionuclides-induced DNA double-strand breaks by γ-H2AX foci in the organs. The micro nuclei test and the tumorigenicity of mouse lung were also examined under the same condition.The number of γ-H2AX focus per hepatic cell was 1.4 (0Bq/ml), 9.5(10Bq/ml), 10.7(100Bq/ml), respectively. It was suggested that the genome damage caused internal low dose ^<137>Cs radiation were occurring chronically even in low dose contaminated area. But no significant difference was observed in the micro nuclei test. In addition, progress data (by 6 animals in each dose groups) is showing that the number of lung tumors per mouse induced by urethane under the same condition is 36.8(368/10) (0 Bq/ml), 44.1 (441/10) (10Bq/ml), 44.1 (441/10) (100Bq/ml), and the average of tumor diameter (mm) is 1.64, 1.67, 1.68, respectively.