METHODOLOGY FOR THE ASSESSMENT OF INGESTED ACTINIDES FROM MONTE CARLO SIMULATION OF VOXEL PHANTOM.
Radiat Prot Dosimetry
; 173(4): 308-317, 2017 Apr 15.
Article
in En
| MEDLINE
| ID: mdl-26922786
ABSTRACT
In case of internal contamination of actinides by ingestion pathway, activity will be transferred to various regions of the alimentary tract over a period of time. In this article, counting efficiencies (CEs) of Phoswich and an array of HPGe detectors are estimated for source in alimentary tract of voxel phantom. The phantom as well as Phoswich, and an array of three HPGe detectors are incorporated in Monte Carlo code 'FLUKA'. Human alimentary tract model is solved using default parameters to identify different compartments where activity will accumulate after an ingestion intake of 1 Bq as a function of time. Accordingly, CEs are evaluated on 0.5-5 d post ingestion intake for the source distributed in the contents of alimentary tract for photon energies in 18-238 keV range representing sources of actinides. The assessment of ingested activity of actinides from abdomen measurements is discussed. Higher CEs are observed with Phoswich detector compared with HPGe array due to its large size and high effective Z. Also, the CEs observed on Days 1-5 using both the detectors are found to decrease by 16-75 % with respect to the CE on half day. Thus, there is need to use CEs according to the observed activity distribution post ingestion intake. The contribution in the abdomen measurements due to source in the lungs and vice versa is also studied for intake by both inhalation and ingestion pathways. The contribution of source in the liver is found to be â¼30-50 % in chest and 75 % in abdomen measurements.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Monte Carlo Method
/
Actinoid Series Elements
/
Phantoms, Imaging
Type of study:
Health_economic_evaluation
Limits:
Humans
Language:
En
Journal:
Radiat Prot Dosimetry
Year:
2017
Document type:
Article
Affiliation country:
India