Revisions to the ORNL series of stylized mathematical models of the human body.
Health Phys 2003 Jun; 84(Suppl):S198
The development of extensions and improvements to the mathematical model series originally developed at the Oak Ridge National Laboratory is represented. These models incorporate the revised MIRD model of the head and brain and the ORNL model of the torso and legs. Other revisions included the addition of an esophagus, a prostate gland, a four-region kidney (to include a medulla, cortex, papillary, and pelvic region), a mucosal layer within walled organs (GI tract, gall bladder, and urinary bladder), and the inclusion of a rectum separate from the sigmoid colon. Extrathoracic and thoracic airways regions are additionally identified to represent the ETI and ET2 regions of the ICRP 66 respiratory tract model. The mathematical model series are utilized to reassess photon absorbed fractions as well as to estimate electron absorbed fractions for self- and cross-organ irradiation for internal dose calculation. This effort is necessary due to changes in the model geometries noted above, as well as the lack of systematic tabulation of electron absorbed fractions. From this study, current ICRP and MIRD methodologies are shown to overestimate organ self-dose containing high-energy beta emitters. Comparisons are made to the standard assumption made by both MIRD and the ICRP that 100% of electron emission energy is locally deposited.
Nuclear-energy; Radiation-exposure; Radiation-facilities; Employee-exposure; Exposure-assessment; Mathematical-models; Dose-response; Cancer; Body-distribution; Organs; Humans; Nuclear-radiation; Electron-radiation; Irradiation; Models
University of Florida, Nuclear and Radiological Engineering, Gainesville, FL 32611
Abstract; Conference/Symposia Proceedings
University of Florida, Gainesville, Florida