Abstract
We used imaging plates (IP), sensitive to beta rays, in the present paper to obtain the images of beta ray emitters in the sample. Detection of radiation with IPs is based on optically stimulated luminescence which is accumulated in the lattice defect in the plate with (BaFBr:Eu2+) by radiation.
We examined mammal teeth taken in contaminated areas in the former Soviet Union. A part of the south Ural region, Russia, was contaminated by the chemical explosion of a radioactive waste facility in 1957. 467 nuclear tests were conducted from 1940 to 1949 at a Semipalatinsk test site, some of which contaminated nearby villages. The mammal tooth samples from these regions contain 90Sr, detectable by IP. After slicing the samples to a thickness of 1mm, they were placed on an imaging plate together with standard samples for one week in a lead cave, protecting natural radiation from the outside. The plates were measured by Fuji BAS-1800-2, the obtained images processed with Multi Gauge v. 3.0. The average concentrations of 90Sr in the samples were obtained by comparing the intensities of the luminescence to those of the standard samples.
A sample from Ozerskoe, Russia, with the highest contamination, showed 10.0 Bq/g of 90Sr while one from Argayash, with lower contamination showed 0.03 Bq/g, which was correlated with the soil contamination level. A sample from a location close to the center of explosion at the Semipalatinsk test site showed 1.87 Bq/g, while one from the Maysk district showed 0.50 Bq/g where people are raising cows.
Key words
Imaging Plate, 90Sr, radiation accident
