Abstract
Purpose: To estimate the biological doses for two severely exposed subjects (A and B) in a radiation accident in Shandong Jining, China in 2004.
Materials and methods: Conventional chromosome aberration analysis and cytokinesis-block micronuclei (CBMN) assay were performed in peripheral blood and bone marrow samples on two subjects after the accident. A new dose-effect curve and the nuclear division index (NDI) obtained from in vitro irradiation experiments using high dose of 60Co γ-rays were used to estimate the exposed doses.
Results: No metaphases or binucleated cells were observed in the peripheral blood cultures from either of the subjects. However, metaphases and binucleated cells were obtained from both subjects after bone marrow cultures. Both dicentric/ring and micronuclei yields were very high. The dose estimated for A and B were 20.0 Gy and 8.8 Gy, respectively, by dicentric/ring scoring, similar to the data by combination of the CBMN and NDI (CBMN + NDI) assay. The estimated doses by the two methods were in accordance with the clinical symptoms.
Conclusion: The new curve, together with the CBMN + NDI assay, are reliable for estimating higher doses of irradiation. In future radiation accidents, the accuracy and significance of these methods can be further tested.
Acknowledgements
We wish to thank Prof. Li Chen-lin in the Beijing Institute of Radiation Medicine for his help in vitro irradiation experiments. We are grateful to Prof. Liu Bing in Oncology Laboratory in the 307 Hospital, Beijing, for his help in grammatical modification.
Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.