Tellurium interference in /sup 129/I activation analysis

Measurement of /sup 129/I at low levels is required for effluent control, environmental assessment and tracer studies in the natural environment. Low level /sup 129/I analysis has also been used for measurement of natural-fission-produced /sup 129/I in minerals and ores as well as meteorites. The most sensitive method for /sup 129/I measurements is neutron activation analysis of iodine separated from a suitable sample. Minimum sample processing prior to neutron activation is desirable in order to reduce chances of sample contamination with uranium or /sup 129/I. A potential interference in the activation analysis method is the production of /sup 129/I (/sup 130/I) from Te impurities in the irradiated ampoule. Procedures have been developed and applied to measurement of the magnitude of the potential Te interference. One-tenth of a microgram of Te in the irradiated ampoule is sufficient to produce interference in the analysis. This is detectable by either radiochemical Te measurements or by /sup 131/I detection in the iodine fraction from the irradiated ampoule. This paper discusses the procedures and results of Te interference studies in /sup 129/I activation analysis. The interference was found to be insignificant for most analyses. 5 tables.