Development and characterization of a novel variable low dose-rate irradiator for in vivo mouse studies.
Radiation exposure of humans generally results in low doses delivered at low dose rate. Our limited knowledge of the biological effects of low dose radiation is mainly based on data from the atomic bomb Life Span Study (LSS) cohort. However, the total doses and dose rates in the LSS cohort are still higher than most environmental and occupational exposures in humans. Importantly, the dose rate is a critical determinant of health risks stemming from radiation exposure. Understanding the shape of the dose-rate response curve for different biological outcomes is thus crucial for projecting the biological hazard from radiation in different environmental and man-made conditions. A significant barrier to performing low dose-rate studies is the difficulty in creating radiation source configurations compatible with long-term cellular or animal experiments. In this study the design and characterization of a large area, I-based irradiator is described. The irradiator allows continuous long-term exposure of mice at variable dose rates and can be sited in standard animal care facilities. The dose rate is determined by the level of I activity added to a large NaOH-filled rectangular phantom. The desired dose rate is maintained at essentially constant levels by weekly additions of I to compensate for decay. Dosimetry results for long-term animal irradiation at targeted dose rates of 0.00021 and 0.0021 cGy min are presented.
Olipitz
Werner
W
Department of Biological Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA.
Hembrador
Sheena
S
Davidson
Matthew
M
Yanch
Jacquelyn C
JC
Engelward
Bevin P
BP
D000818:Animals; D019583:Dose Fractionation, Radiation; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007457:Iodine Radioisotopes / Q000032:analysis*; D051379:Mice; D011829:Radiation Dosage; D015203:Reproducibility of Results; D012542:Scattering, Radiation; D012680:Sensitivity and Specificity; D014916:Whole-Body Irradiation / Q000295:instrumentation* / Q000662:veterinary*
D007457:Iodine Radioisotopes
Proc Natl Acad Sci U S A. 2003 Nov 25;100(24):13761-6
14610281
Proc Natl Acad Sci U S A. 2000 May 9;97(10):5381-6
10792040
Radiat Res. 1983 Apr;94(1):105-34
6856762
J Radiat Res. 2004 Dec;45(4):521-5
15635261
Int J Radiat Biol. 1995 Jul;68(1):47-54
7629437
Health Phys. 2009 Jul;97(1):1-5
19509507
Radiat Res. 1979 Nov;80(2):325-42
504579
Radiat Res. 2008 Mar;169(3):311-8
18302492
Radiat Res. 1982 Sep;91(3):447-56
7122826
Radiat Res. 2004 Oct;162(4):377-89
15447045
Br J Radiol. 2001 Jan;74(877):56-61
11227778
Radiat Res. 1990 Jun;122(3):316-25
2356286
J Nucl Med. 1997 May;38(5):727-31
9170437
Int J Radiat Biol. 1998 May;73(5):535-41
9652811
J Radiol Prot. 2006 Sep;26(3):317-24
16926474
Ann ICRP. 1991;21(1-3):1-201
2053748
Radiat Res. 1973 May;54(2):316-27
4735769
Radiat Res. 2002 Sep;158(3):311-8
12175308
Radiat Res. 2007 Apr;167(4):417-37
17388697
Proc Natl Acad Sci U S A. 2003 Apr 29;100(9):5057-62
12679524