Long-lived radionuclides ultratrace analysis

Becker JS, Pickhardt C, Dietze H-J (2000) Laser ablation inductively coupled plasma mass spectrometry for the trace, ultratrace and isotope analysis of long-lived radionuclides in solid samples. Inti J Mass Spectrom 202 283-297... 

Another combination of magnetic and electric sector fields, together with a tandem accelerator, is realized in different types of accelerator mass spectrometers (AMS)17 applied for carbon-14 dating and extreme ultratrace analysis of long-lived radionuclides at natural isotope abundances (see Chapter 5). 

Long-lived radionuclides occur at extremely low concentrations, especially in environmental samples, therefore several authors have proposed matrix separation and enrichment of the analytes before analysis.21,24,26,3 39 Radiochemical methods often require very careful and time consuming separation and enrichment processes and measurement procedures of a-, (3- and -emitting radioactive species at the trace and ultratrace level using conventional radioanalytical techniques 40-43 Trace/matrix separation, which is performed offline or online in order to avoid possible isobaric interferences, matrix effects and to reduce the detection limits for the determination of long-lived radionuclides, is also advantageous before ICP-MS measurements as the most widely applied mass spectrometric technique. 

Ultratrace Analysis of Long-lived Radionuclides in Very Small Sample Volumes... 

Actinides were determined at the ultratrace level in moss samples collected from the eastern Italian Alps (1500 m a.s.l.). The frozen samples were cut into 1-2 cm sections and analyzed separately to obtain the distribution curves of the vertical concentrations. For plutonium and americium isotope analysis, 1-2 g of the samples were ashed, leached, separated with respect to analytes and analyzed by alpha spectrometry and LA-ICP-MS after the plutonium or americium had been electroplated on a stainless steel disk.23 Estimated limits of quantification of LA-ICP-MS for actinide radionuclides deposited on stainless steel plates after chemical separation are summarized in Table 9.45. For most of the long-lived radionuclides in moss samples, lower limits of determination were found at the 10 15gg 1 concentration level compared to those of a - spectrometry 23... 

Other mass spectrometric techniques such as RIMS and AMS possess high isotope selectivity for extreme ultratrace and isotope analysis of, in particular, radiotoxic isotopes ( C, "Ca, Sr, Tc, Pb, U and plutonium isotopes) in the environment, in cosmochemistry, radiodating, nutrition and biomedical research. RIMS has become as an nltrasensitive and selective analytical technique for the determination of extremely low isotope abundances. In spite of the excellent analytical features of RIMS (detection limit for isotopes 10 atoms per sample) and exciting applications for the determination of extremely low abundances and isotope ratios of long-lived radionuclides, such as all plutonium isotopes (including Pu), U or " Ca, but no commercial instrument is available on the analytical market. 

Trace, Ultratrace and Surface Analysis 415 9.9 Determination of Long-lived Radionuclides... 

Besides the analysis of nuclear fuel and of radioactive waste materials, the determination of contamination and enrichment of selected radioactive nuclides, e.g., which is one of the most important environmental indicators of nuclear accidents, Se, Tc, Np, Pu, °Pu and "Am at ultratrace concentration levels, is useful for environmental monitoring of fallout from nuclear weapons testing, nuclear power plants or nuclear accidents. ". Selected application fields for the determination of natural and artificial long-lived radionuclides (LLR) and radionuclides investigated by mass spectrometric techniques are summarized in Tables 9.36 and 9.37, respectively. 

Becker J. S., Dietze H. J., McLean J. A. and Montaser A. (1999) Ultratrace and isotope analysis of long-lived radionuclides by inductively coupled plasma quadrupole mass spectrometry using a direct injection high-efficiency nebulizer, Anal Chem 71 3077-3084. 

Becker, J.S. Dirtze, H.J. AppUcation of Double-Focusing Sector Held ICP Mass Spectrometry with Shielded Torch Using Different Ndiulizers for Ultratrace and Precise Isotope Analysis of Long-Lived Radionuclides. J. Anal. Atom. Spectrom. 1999,14, 1493-1500. 

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