HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Murthy, G. K. Articles by Campbell, J. E. Search for Related Content PubMed Articles by Murthy, G. K. Articles by Campbell, J. E.

A Simplified Method for the Determination of Iodine¹³¹ in Milk

Milk and Food Research Program Robert A. Taft Sanitary Engineering Center, Cincinnati, Ohio

ABSTRACT

A simplified method has been developed for the determination of iodine¹³¹ (I¹³¹) in milk. This method is suitable for surveillance purposes and can be employed in conjunction with the strontium⁹⁰ determination described by Murthy et al. (12). It is based on the gross -counting of proteins obtained by trichloroacetic acid precipitation of milk preserved with formaldehyde. Formaldehyde favors a reaction wherein the inorganic form of I¹³¹ present in milk is transformed into protein-bound I¹³¹. Work is under way to determine the mechanism of this reaction, which is not clearly understood. The method is simple and accurate, and results are comparable to those obtained by gamma spectrometric methods (2). It involves no instruments other than a shielded 2-in. solid NaI (thallium-activated) crystal with a photomultiplier assembly fed through a cathode follower and coupled directly to a decade scaler. These instruments ordinarily are available in any radiochemical laboratory. The recovery of I¹³¹ is 98 ± 2% and the presence of -emitting K⁴⁰, Cs¹³⁷, and Ba¹⁴⁰ + La¹⁴⁰, usually found in milk, has no effect on the I¹³¹ determination.