THE TURNOVER OF STRONTIUM-85 IN MAN AS DETERMINED BY WHOLE-BODY COUNTING

Journal Article · Wed Aug 01 04:00:00 EDT 1962 · Radiation Research

DOI:https://doi.org/10.2307/3571307· OSTI ID:4810045

Cohn, S H; Spencer, H; Samachson, J; Robertson, J S

The retention of intravenously administered tracer doses of Sr/sup 85/ was measured in ten patients directly by in vivo whole-body counting, and indirectly by the analysis of the urinary and fecal Sr/sup 85/ excretions. Sr/ sup 85/ retention determined by the two methods differed during the first few days after administration of the isotope, inasmuch as the changing pattenn of tissue distribution of the Sr/sup 85/ altered the geometry and thus the counting efficiency of the NaI crystal detector of the whole-body counter. Retention in long-term studies can be expressed either as a series of exponentials or as a single-termed power function. The mean biological half-life of Sr for six comparison patients, based on the turnover of the slowest exponential component, was 843 days, as determined during the period 100 to 320 days. The mean value for radiostrontium retention, R, as a function of time for these six patients in the period 30 to 397 days after intravenous injection of the Sr/sup 85/ was given by the power R = 52.2t/sup -0.175/. Although both the exponential and the power function represent satisfactorily the experimental data obtained during the first year, the long-term projections of these functions diverge widely. As the final exponential term from which the half-life value is derived has been shown to depend on the period of time over which it is determined, it is preferable to use the power model to estimate retention over long periods. If the data are fitted with a power function aad projected to 40 years, the half-life of the equivalent exponential term fitted to the period 20 to 40 years is 110 years in this study. More long-term data on the retention of isotopes are essential in order to provide a basis for choosing between the two mathematical models used to describe the biological turnover of Sr over a human life span. Use of the whole-body counter appears to be an excellent method for obtaining data on the retention of alkaline earths. Unfortunately. Sr/sup 85/ has too short a life for very long- term turnover studies. Where Sr/sup 85/ can be used, however, measurement with the whole-body counter appears to be an excellent method of studying its retention in human subjects. (auth)

• Research Organization: Brookhaven National Lab., Upton, N.Y.
• Sponsoring Organization: USDOE
• NSA Number: NSA-16-026710
• OSTI ID: 4810045
• Journal Information: Radiation Research, Journal Name: Radiation Research Vol. Vol: 17
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

BIOLOGY AND MEDICINE
BODY
CRYSTAL COUNTERS
FECES
HALF-LIFE
MAN
MATHEMATICS
MEASURED VALUES
METABOLISM
QUANTITATIVE ANALYSIS
QUANTITY RATIO
SODIUM IODIDES
STRONTIUM 85
TRACER TECHNIQUES
URINE