In vivo determination of $sup 90$Sr by analyzing bremsstrahlung from the skull

Conference · Sat Jan 01 04:00:00 EST 1972

OSTI ID:4310498

Olson, D G; Willis, C A ^[1]

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1. ed.

From third Health Physics Society midyear topical symposium; Los Angeles, California, USA (29 Jan 1969). See CONF-690103P1. A method is described for the direct in vivo determination of /sup 90/Sr by measuring the bremsstrahlung. Less than 0.02 of a maximum permissible body burden can be detected in a 10-min. count. Because the skull constitutes a major part of the skeleton covered only by a thin layer of tissue, the detector is placed alongside the head to obtain maximum sensitivity. In addition, this configuration minimizes the interference from radioactive contamination in the trunk of the body, particularly in the lungs, muscle, and gastrointestinal tract. Even though the contribution from contamination is minimized, the bremsstrahlung region of the spectrum is adjusted for even small quantities of gamma emitters by concurrently counting counting the whole-body and the skull to determine quantitative correction factors. Bremsstrahlung spectra from over l50 humans with normal quantities of in vivo radioactivity are used to ascertain the counts required to correct for background. The system was calibrated by inserting 100 capsules of /sup 90/Sr-/sup 90/Y in the skeleton of a Rando phantom on a proportional weight basis. Three levels of activity covering the range from 1 to 8 mu Ci were measured to obtain a detection efficiency of 1100 plus or minus 33 c/m/ mu Ci of /sup 90/Sr in the 40-120 keV energy region. The prime advantages offered by the technique are that information is available within minutes and, compared to bioassay, the cost per analysis is markedly reduced. (auth)

• Research Organization: Atomic Energy Commission, Idaho Falls, ID
• NSA Number: NSA-29-029854
• OSTI ID: 4310498
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

*SKULL-- RADIOACTIVITY
*STRONTIUM 90-- RADIOMETRIC ANALYSIS
BREMSSTRAHLUNG
CALIBRATION
CONTAMINATION
COUNTING TECHNIQUES
IN VIVO
MAN
N40130 --Chemistry--Analytical & Separations Chemistry--Radiometric & Radiochemical Procedures
N48710* --Life Sciences--Nuclide Kinetics & Toxicology--Man
N80400 --Law
N80500 --Management
PHANTOMS
RADIATION DETECTORS
RADIATION DOSES
SPECTRA
WHOLE-BODY COUNTING