Determination of 210Po in mineral waters by sorption on ZnS(Ag)

210Po occurs in small amounts as a member of 238U decay chain. It occurs in very small amounts in uranium ore, cigarette smoke because of short half-life of its all isotopes as well as in households as a product of transformation of 222Rn and its daughters products. It can be found naturally in the air, water, biota and in food, too. The determination of 210Po was performed according to Czech state norm CSN 75 7626 Quality of waters - Determination of polonium 210. The aim of our study was the optimization of sorptive conditions of 210Po from model solutions and determination of volume activity of 210Po in the samples of bottled mineral waters commonly available in Slovak markets. Radiochemical yield was studied by the method of addition of internal standard, the solution of 210Pb (in equilibrium with 210Po and with the volume activity 1 Bq.cm-3) as a tracer was used. The method we used is sufficiently sensitive and precise for monitoring of volume activity of 210Po in drink water and also for mineral waters with increased salinity (up to 5 g.dm-3). 210Po volume activities of all mineral waters which were determined do not exceed the highest permissible 210Po volume activity value for natural mineral water in accordance with the notice No. 345/2006 of the Ministry of Health of the Slovak Republic. (author)