Applications of PERALS-Alpha Spectrometry for the Investigation of Radionuclides in Water Samples

In this paper, experiences of the last 20 years with PERALS-technique are described. PERALS stands for photo electron-rejecting alpha liquid scintillation. This scintillation technique was developed by Jack McDowell in 1970s and is a powerful analyses many natural nuclides also beta nuclide 90Sr. The principle based on selective extraction radionuclide from water phase means complexing or ion pair reagent. extractant contains cocktail suitable counting. Therefore, extract can be analyzed directly after step. After removing quenchers, such as oxygen, proper setting pulse shape discriminator, pulses counted photomultiplier. paper describes development robust analysis schemes determination traces polonium, thorium, uranium other actinides samples (groundwater, rain water, river drinking mineral sea water). For radon radium, enrichment poor. methods not trace these analytes. addition, beta-emitter 90Sr discussed, even though its spectrum counter. Results survey Switzerland presented every radio element.