|
|
The Journal of the Korean Society for Therapeutic Radiology and Oncology 2000;18(2): 138-149. |
| The Frequency of Chromosomal Aberrations of Peripheral Lymphocytes according to Radiation Dose and Dose Rate |
| Tae Sik Jeong, Heum Man Baek, Byung Chul Shin, Chang Woo Moon, Mi Hyang Kim, Yong Hwan Lee, Ha Yong Yum |
1Department of Radiation Oncology, Kosin Medical College and Medical Center, Pusan, Korea.
2Department of Clinical Pathology, Kosin Medical College and Medical Center, Pusan, Korea.
3Department of Preventive Medicine, Kosin Medical College and Medical Center, Pusan, Korea. |
|
|
|
|
|
| ABSTRACT |
PURPOSE:
It was studied that the relationship between radiation dose, dose rate and the frequency of chromosomal aberrations in peripheral lymphocytes.
METHODS AND MATERIALS: Peripheral lymphocytes were irradiated in vitro with 6 MeV X-ray at dose ranges from 50 cGy to 800 cGy. The variations of the frequency of chromosomal aberrations were observed according to different radiation dose rate from 20 cGy/min to 400 cGy/min at constant total dose of 400 cGy which it was considered as factor to correct biological radiation dose measurement.
RESULTS:
The yields of lymphocytes with chromosomal aberrations (dicentric chromosome, ring chromosome, acentric fragment pairs) are 0% at 50 cGy, 9% at 100 cGy, 20% at 200 cGy, 27% at 300 cGy, 55% at 400 cGy, 88% at 600 cGy, and 100% at 800 cGy. The value of Ydr is 0.000 at 50 cGy, 0.093 at 100 cGy, 0.200 at 200 cGy, 0.364 at 300 cGy, 0.612 at 400 cGy, 2.040 at 600 cGy, and 2.846 at 800 cGy. The relationship between radiation (D) and the frequency of dicentric chromosomes and ring chromosomes (Ydr) can be expressed as Ydr=0.188x10-2/GyxD+0.422x10-4/Gy2xD2. The value of Qdr is 0.000 at 50 cGy, 1.000 at 100 cGy, 1.000 at 200 cGy, 1.333 at 300 cGy, 1.118 at 400 cGy, 2.318 at 600 cGy, and 2.846 at 800 cGy. When 400 cGy is irradiated with different dose rate each of 20, 40, 60, 80, 100, 160, 240, 320, and 400 cGy/min, Ydr is each of 0.982, 0.837, 0.860, 0.732, 0.763, 0.966, 0.909, 1.006, and 0.806, and Qdr is each of 1.839, 1.565, 1.654, 1.333, 1.381, 1.750, 1.6000, 1.710, and 1.318.
CONCLUSION:
There are not the significant variations of Ydr and Qdr values according to different dose rate. And so radiation damage is influenced by total exposed radiation doses and is influenced least of all by different dose rate when it is acute single exposure. |
| Key Words:
X-ray radiation, Dose rate, Lymphocytes, Chromosome aberration, Biological dosimetry |
|
|
|
PDF Links
Full text via DOI 
Download Citation 
