"Dynamic analysis on three indexes of biological dose estimation of the victim exposed to 192Ir radiation source at ""5.7"" accident in Nanjing" / 中华放射医学与防护杂志

ABSTRACT

Objective To explore the natural attenuation pattern of three biological dose estimation indexes in vivo by investigating the effect on biological dosimetry of peripheral blood sampling at different time points from the victim partially exposed to 192Ir radiation source at5.7 accident in Nanjing.Methods Peripheral blood of the patient was collected on days 5,40 and 280 after exposure,respectively.The yields of dicentrics plus rings chromosomes (dic + r),cytokinesis-block micronuclei (CBMN) and nucleoplasmic bridge + fusion + horse shoe + circular(NPB + FHC) were analyzed.The dynamic reduction and dose estimation were both observed using the biomarkers mentioned above after exposure.Results Compared to the estimates on days 5 after exposure,the dose values estimated on days 40 and 280 decreased by 34％ and 49％ fordic + r method,48％ and 79％ for the CBMN assay,and 48％ and 75％ for NPN + FHC method,respectively.Conclusions Three biological dose estimation indexes show a progressive decrease in vivo,with the half-life of dic + r/cell being 40 days.The doses estimated using these three indexes on days 40 after exposure showed a relative deviation more than 20％ compared with those on days 5 after exposure.