Akademik Veri Yönetim Sistemi
INTERNATIONAL JOURNAL OF ENVIRONMENTAL ANALYTICAL CHEMISTRY, 2022 (SCI-Expanded)
Monitoring of the anthropogenic radionuclides (Sr-90,Cs- 135 and Cs-137) in different components such as spinach, milk, meat, soil and the grass is important for the environmental radiological survey. Nuclear weapons testing in the atmosphere, nuclear power plant accidents and leaks from the nuclear fuel cycle are the main sources of these radionuclides. The amounts of Sr-90/Y-90 detected in the environment are mostly due to fallout from nuclear weapons testing. Because of its long physical (28.5 years) and biological half-lives (approximately 12 years) and high fission yield, the measurement of Sr-90 is also necessary for radiation protection purposes. It accumulates in bone tissue when ingested by humans through the food chain, and Y-90, a daughter nuclide of Sr-90, emits high-energy beta particles, raising the risk of bone cancer. Strontium has been widely measured in milk samples by using various classical methods. In this study, the procedure we used is based on the separation of Y-90 by HDEHP extraction and counting the Cherenkov radiation using a liquid scintillation spectrometer, Quantulus 1220. Prior to analyses, spiked milk samples were dried and prepared as milk powder. The microwave ashing programme was optimised, and recovery of the radiochemical separation steps was tested for spiked milk powder samples before routine analysis. This method is found to be applicable for the routine analysis of Sr-90 in milk samples after validation of the method by measuring IRMM milk powder samples, too. A lower limit of detection of about 0.02 Bq.kg(-1) was obtained for samples in the case of 84-99% Y chemical yield, 1.45 cpm reagent blank, 4 x 60 minutes counting time and about 83.5 +/- 2.1% counting efficiency.