3例^(60)Co源辐射事故病人受照生物剂量(微核法)估算

Lymphocyte micronuclei dosimetry for three victims accidentally exposed to^(60) Co gamma-rays

目的 用胞质分裂阻滞微核法 (CBMN)对河南“4 2 6”6 0 Co源辐射事故中 3例受照者进行生物剂量估算。方法 照后 10d取血培养 ,0 3ml全血加入到 4ml培养基中 ,37℃培养 44h加松胞素B最终浓度为 6mg·L- 1 ,继续培养 2 8h收获制片 ,CBMN以千分数表示。结果 根据照后 10dCBMN频率估算受照者“梅”、“天”和“旺”的生物学剂量分别为 5 45Gy、2 84Gy和 2 78Gy。该剂量与染色体双 +环及物理剂量相近 ,与临床放射损伤的诊断也相符合。结论 在放射事故中检测CBMN可作为生物剂量计。

Objective The radiation doses were estimated by using the yields of cytokinesis|block micronucleus (CBMN) for three victims of the 60 Co radiation source accident occurred on April 26,1999 in Henan Province. Methods A sample of 0^3 ml heparinized blood,one each taken from the victims on d10 after irradiation,was added into 4 ml culture medium for 44hr|incubation at 37 ℃.Then cyt|B was added to make a final concentration of 6 mg·L -1 .The sample was incubated for another 28hr,then steps of a mild hypotonic treatment,fixation,histopathologic slide preparation and routine staining were performed sequentially.The number of CBMN enumerated in 1000 CB cells is the CBMN rate. Results At d10 after the accident,based on the standard dose|response curve established in this laboratory after in vitro irradiation of human lymphocytes,the equivalent whole body doses for the three victims were estimated to be 5 45 Gy 2^84 Gy and 2^78 Gy.The result is basically correlated with the doses estimated by cytogenetic dosimetry,physical measurement and clinical diagnosis. Conclusion Cytokinesis|blocked micronucleus assay can be used as a biological dosimetry radiation accident.