Studies on Trace Amounts of ¹³⁷Cs in Environmental Samples

—Determination of ¹³⁷Cs in agricultural and livestock products—

Abstract

A convenient method for the determination of trace amounts of¹³⁷Cs in agricultural and livestock products was studied by use of a low back-ground β-ray spectrometer.
Simplification, rapidi fication and accuracy in the determination of trace amounts of ¹³⁷Cs in environmental samples were aimed at and designed.
The β-ray spectra, which were measured by the low back-ground β-ray spectrometer on the counting sample after chemical separation (AMP-H₂PtCl₆ method), were analyzed by means of the weighted least squares method using an automatic analyzer, and then radioactivities of ⁴⁰K, ⁸⁷Rb and ¹³⁷Cs were determined.
The results obtained by this method were in good agreement with the results obtained by conventional method using a low back-ground GM counter after chemical separation (AMP-Bio-Rex·40-H₂PtCl₆ method) in the determination of ¹³⁷Cs, and then applicability for environmental samples was studied. The radioactivity of ¹³⁷Cs only could be determined by this method without using Bio-Rex·40 cation exchange resin to remove impurities such as ⁴⁰K and ⁸⁷Rb.