title: Determination of radium-226 in aqueous solutions by alpha-spectrometry.
abstract: The new European legislation imposes a lower threshold for radioactivity in drinking water. This requires the development of more sensitive and reliable analytical methods. This work presents an improved alpha-spectrometric technique to determine the radium-226 activity in aqueous solution relying on the radium adsorption onto a thin manganese oxide layer followed by alpha-measurement. The preparation of the MnO2 deposit has been optimized as well as the radium adsorption conditions. Detection threshold and limit of 5 and 10 mBq x L(-1), respectively, with a 10% (95% confidence) uncertainty are currently reached. This paper reports on the overall technique and on its application to assess the radium-226 activity in 28 French mineral waters. In addition, the gross alpha- and beta-activities have been evaluated using proportional counting while the uranium concentrations were derived from ICPMS.
authors.affiliation: Laboratoire SUBATECH, UMR 6457, Ecole des Mines de Nantes, IN2P3/CNRS, Université de Nantes, France. morvan@subatech.in2p3.fr
authors.forename: K
authors.initials: K
authors.lastname: Morvan
authors.forename: Y
authors.initials: Y
authors.lastname: Andres
authors.forename: B
authors.initials: B
authors.lastname: Mokili
authors.forename: J C
authors.initials: JC
authors.lastname: Abbe
mesh_terms: D000465:Algorithms; D000512:Alpha Particles; D005602:France; D017895:Manganese Compounds / Q000737:chemistry; D010087:Oxides / Q000737:chemistry; D011883:Radium / Q000032:analysis*; D013057:Spectrum Analysis; D014875:Water Pollutants, Radioactive / Q000032:analysis*; D014881:Water Supply / Q000032:analysis* / Q000592:standards
chemical_list: D017895:Manganese Compounds; D010087:Oxides; D014875:Water Pollutants, Radioactive; C027424:manganese oxide; D011883:Radium