Monitoring of Natural Radioactivity in Drinking Water and Food with Emphasis on Alpha-Emitting Radionuclides

Abstract

Alpha spectrometry is an indispensable technique in the radiology lab for the analysis of natural radionuclides. While the powerful ICP/MS is used more and more for the analysis of uranium and thorium, other radionuclides, such as 226 Ra, are difficult to analyze with this technique due to their very high specific activities. The following chapter is introduced by a description of the problems, which may occur when working in the ultra-trace level. A description of the commonly used extraction and enrichment techniques for alpha nuclides and a short survey of the commonly applied detection techniques are given. The main application of alpha spectrometry in our laboratory is the monitoring of tap and mineral waters. Besides water, some specific food categories, such as fish, seafood, spices or healing earths, are monitored for their content of natural radionuclides. Monitoring of Natural Radioactivity in Drinking Water and Food with Emphasis… DOI: http://dx.doi.org/10.5772/intechopen.90166 * Activity limits according to ordinance on drinking water and water for public baths and shower facilities (TBDV) [7].

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

“…[13][14][15]. The PERALS-spectrometer is well described in the publication of McDowell [8] and in the instruction manual for the PERALS Spectrometer from Ordela Inc [16] (Figure 2).…”

“…For the procedure of extractions, only few materials have to be available: 1 L glass bottles and phase separators fitting on the glass bottles (Figure 3), a magnetic stirrer with magnetic bars, reagent vials and 2 mL culture tubes. Before starting the extraction, the glass bottles have to be cleaned with acid solution to avoid any memory effects or cross contaminations [16]. In the state laboratory Basel-City, the cleaned bottles are rinsed three times with 10 mL of 2 M acid solution (hydrochloric acid or nitric acid).…”

“…LOD for 224 Ra and 226 Ra is 2 mBq/L. The resolution is sufficient to distinguish between the radium peaks and the peaks of their radon and polonium daughters [16].…”

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

“…Scientists successfully introduced the PERALS technique in their laboratories (e.g., [ 13 , 14 , 15 ]). The PERALS spectrometer is well described in the publication of McDowell [ 8 ] and in the instruction manual for the PERALS Spectrometer from ORDELA Inc. [ 16 ] ( Figure 2 ).…”

“…For the procedure of extractions, only a few materials have to be available: 1 L glass bottles and phase separators fitting on the glass bottles ( Figure 3 ), a magnetic stirrer with magnetic bars, reagent vials and 2 mL culture tubes. Before starting the extraction, the glass bottles have to be cleaned with acid solution to avoid any memory effects or cross contaminations [ 16 ]. In the state laboratory of Basel–City, the cleaned bottles are rinsed three times with 10 mL of 2 M acid solution (hydrochloric acid or nitric acid).…”