Determination of uranium and polonium in <span style="font-style:italic">Sparus aurata</span> by alpha spectrometry

Abstract

The aim of this study was optimizing conditions for the specific activities determination of some uranium-series radionuclides present in Sparus aurata by alpha spectrometry. Determinations of specific activities were conducted varying the type of digestion: acid attack on hot plate, controlled microwave digestion and acid attack after calcination of the sample. The latter procedure was applied only to the case of uranium isotopes determination. The variation in the isotope extraction method consisted of applying the techniques of liquid-liquid extraction using Tributyl phosphate (TBP) or chromatographic UTEVA resin. Results depending on the type of treatment given to the samples were compared based on obtained chemical yields. The results reveal a higher bioaccumulation of polonium in the liver sample, with activities of 0.809, 2.495 and 2.439 Bq kg$^{ - 1}$ fresh wt compared with the fillet. The best chemical yields for polonium were close to 60% for samples that were digested by microwave. In the case of uranium the best chemical yields, close to 80% for fillet, were obtained with a previous calcination of the sample and using the UTEVA resin.