OBJECTIVE:
To estimate the
biological dose by the
chromosome aberration analysis in a victim suffered in the radioactive source-loss
accident in Nanjing City.
METHODS:
Peripheral
blood sample of the victim was collected 6 days after radioactive exposure. Individual radioactive
biological dose was estimated by identifying the aberration of the dicentrics plus centric rings in the
metaphase chromosome of
cells. The distribution of
chromosome aberration was tested by the
Poisson distribution. Impure
Poisson distribution was used to estimate the
radiation dose.
RESULTS:
Among the 353
cells observed at
metaphase,75 aberration of dicentrics plus centric rings were found,43
cells had 1 aberration and 7
cells had 2 aberrations. Moreover,there were 3 multi-aberration
cells with 3,4 and 11 aberrations respectively. The average individual
radiation dose was estimated to be 1. 52 Gy,which was consistent with the
clinical diagnosis as mild acute
bone marrow radiation disease. The
Poisson distribution u test revealed that the
patient suffered from nonhomogeneous
radiation.By the impure
Poisson distribution test,the
radiation exposure proportion of the whole body was estimated to be 55% and the average
dose was 3. 02 Gy.
CONCLUSION:
The
biological dose estimation was successfully performed,the results showed that this was a case of nonhomogeneous irradiation.